Patent Publication Number: US-10325323-B2

Title: Providing a claims-based profile in a social networking system

Description:
BACKGROUND 
     This invention relates generally to social networking, and in particular to evaluating assertions made in a social networking system. 
     In recent years, social networking systems have enabled users to share information about themselves, their friends, and their interests and preferences in real-world concepts with other users and entities, such as their favorite movies, musicians, celebrities, soft drinks, hobbies, sports teams, and activities. Users may include biographical information about themselves, such as where they grew up, what colleges and universities they attended, where they have worked, and so forth. A social graph of nodes interconnected by edges may be created through these interactions between users, entities, and other nodes on social networking systems. The edges representing interactions between the nodes have been assumed to be based on absolute truth and have been generated from the perspective of the user. In this way, a user may express interests and share information with other users and entities in social networking systems. 
     While social networking systems have provided tools for users to share information about themselves, this information has been accepted as an absolute truth, even where some uncertainty may exist in the statements. For example, a user may state that he or she is from Dallas, Tex., when in fact the user is from a nearby suburb of Dallas, Tex. As a result, the social networking system provides inaccurate information about the hometown of the user to other users of the social networking system. This may lead to ineffective targeted advertising directed towards the user based on inaccurate information. Further, the user experience is diminished because of the inaccurate information being provided. 
     Specifically, social networking systems have not provided tools or mechanisms for handling the uncertainty of statements made in building the social graph of interactions between users, entities, and interests. Accurate information about users, their connections with other users, and entities on social networking systems, as well as their interests and preferences provides a better user experience while enabling third-party developers to more accurately target users and better build applications that seek to drive traffic and increase engagement with their websites. Advertisers also benefit from accurate information in marketing interest-based goods and services to users of the social networking system. However, existing systems have not provided efficient mechanisms of identifying and evaluating assertions made by users in building a social graph. 
     SUMMARY 
     A social graph, which records the actions of users in a social networking system, may be modeled at least in part as a collection of claims. Each claim is associated with an author, an audience, and content that represents an assertion. Probabilistic information may be collected from various sources for a claim, and a social networking system may then evaluate a measure of truthfulness of the assertion made in the claim. This evaluation may depend on a subjective point of view such that different users have a different measure of truthfulness about the same claim or about an assertion made in the claim. In various embodiments, a user, entity, or application may make assertions in the social networking system, and these may be modeled as claims. Reputation scores may be determined for users based on evaluations of their historical assertions. Claims may be evaluated for truthfulness, from the perspective of a particular viewer, using a probabilistic prediction model that employs, for example, heuristics analysis, regression analysis, and/or machine learning methods. The modeling of these interactions as claims enables many applications in a social networking environment. For example, a contacts application may provide profile information about users of the social networking system to viewers based on the contexts in which the claims about the users&#39; profile information were made. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a high level block diagram illustrating a prior art process of modeling user interactions on a social networking system onto a social graph of nodes and edges. 
         FIG. 1B  is a high level block diagram illustrating a process of providing structure for claims in a social networking system, in accordance with an embodiment of the invention. 
         FIG. 1C  is a high level block diagram illustrating a process of modeling interactions on a social networking system as a collection of claims, in accordance with an embodiment of the invention. 
         FIG. 2  is a network diagram of a system for evaluating claims in a social networking system, showing a block diagram of the social networking system, in accordance with an embodiment of the invention. 
         FIG. 3  is a flowchart of a process of evaluating a claim in a social networking system, in accordance with an embodiment of the invention. 
         FIG. 4  is an interaction diagram illustrating a process of evaluating multiple claims about the same subject in a social networking system, in accordance with an embodiment of the invention. 
         FIG. 5  is a high level block diagram illustrating a process of evaluating claims in a social networking system, in accordance with an embodiment of the invention. 
         FIGS. 6A and 6B  are examples of an application on a social networking system that provides information to viewers based on evaluated claims, in accordance with an embodiment of the invention. 
     
    
    
     The figures depict various embodiments of the present invention for purposes of illustration only. One skilled in the art will readily recognize from the following discussion that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the invention described herein. 
     DETAILED DESCRIPTION 
     Traditional Social Graph with Nodes and Edges 
     A social networking system offers its users the ability to communicate and interact with other users of the social networking system. Users join the social networking system and add connections to a number of other users to whom they desire to be connected. Users of social networking system can provide information describing them which is stored as user profiles. For example, users can provide their age, gender, geographical location, education history, employment history and the like. The information provided by users may be used by the social networking system to direct information to the user. For example, the social networking system may recommend social groups, events, and potential friends to a user. A social networking system may also enable users to explicitly express interest in a concept, such as celebrities, hobbies, sports teams, books, music, and the like. These interests may be used in a myriad of ways, including targeting advertisements and personalizing the user experience on the social networking system by showing relevant stories about other users of the social networking system based on shared interests. 
     Social networking systems have previously modeled interactions, relationships, and other social information using a social graph, which includes nodes connected by edges. Nodes may include users, entities, and objects of the social networking system, such as web pages embodying concepts. Edges represent a particular interaction between two nodes, such as when a user creates a new connection with another user or expresses an interest in a web page about a new movie. The social graph may record interactions between users of the social networking system as well as interactions between users and objects of the social networking system by storing information in the nodes and edges that represent these interactions. Custom graph objects and graph actions may be defined by third-party developers as well as administrators of the social networking system to define attributes of the graph objects and graph actions. For example, a graph object for a movie may have several defined attributes, such as title, actors, directors, producers, year, and the like. Custom graph objects and graph actions are further discussed in a related application, “Structured Objects and Actions on a Social Networking System,” U.S. patent application Ser. No. 13/239,340, filed on Sep. 21, 2011, hereby incorporated by reference. 
     As illustrated in  FIG. 1A , node A  102 , which may represent a user of the social networking system  100  (as depicted in  FIG. 2 ), may perform an action in the social networking system  100 , such as clicking on a “like” link on another node B  104 , which may represent another user, entity, or object of the social networking system  100 , such as a page for Lady Gaga. This action creates an edge  110 . Similarly, a node C  106  and a node D  108  may also perform actions on the social networking system  100 , such as sharing a link, commenting on a photo, establishing a connection to another node B  104 , and the like. In  FIG. 1A , node C  106  and node D  108  may generate edges  112  and  114  with node B  104  through interactions such as clicking on a “like” link on the node B  104 . As a result, the social networking system  100  may assume that node A  102 , node C  106 , and node D  108  are all interested in node B  104  and may aggregate the “likes,” or expressions of interest, as a result. Applications on the social networking system  100  may query the total number of “likes” in order to approximate how interested users may be in other users, entities, and concepts on the social networking system  100 . In this prior art system of structuring the social graph, the fundamental building blocks of the social graph rely heavily on this actor-actee relationship to create nodes and edges. Two different users of the social networking system  100  would see the same the total number of “likes” for a Lady Gaga page on the social networking system  100 . 
     Claims Overview 
     Instead of or in addition to modeling the social graph using nodes and edges, the social networking system  100  may be structured on top of a collection of claims made by users and entities of the social networking system  100 . A claim, as stored as a data structure in the social networking system  100 , includes some or all of the following components:
         Author   Owner   Assertion   Audience   Copyrights   Metadata associated with the claim by the social networking system       

     A user may make a number of “claims” on a social networking system, such as having attended a certain college, working for a certain company, being raised in a certain location, or being friends with other users of the social networking system. Claims on a social networking system include other declared user profile information, such as where the user currently lives and other biographical information about the user, including the age, gender, hometown, dating interests, relationship status, languages spoken, religious beliefs, and political views, as well as other information, including contact information, work and education experience, family members, historical events posted to a timeline, and favorite quotes. 
     Claims may be “authored” by “agents” of the social networking system  100 , such as users, entities, and application authorized to act on behalf of an agent. An author agent  118  may designate an “owner” to assign ownership of a claim. An owner agent  128  may specify certain settings for a claim, such as whether the claim may be copied by other agents and whether the claim may be boosted in rankings by other agents. Copyrights  132  may be set by the owner agent  128  through an interface with the social networking system  100  to set a user-payload bit  134  to allow other agents to copy the payload of the claim into a new claim. 
     Each claim includes an “assertion” that includes a “payload” of content that is written to the social graph. The payload of content is the core of an assertion. In one embodiment, the payload may be formed as a subject which is an object the assertion is describing. In another embodiment, the payload may be formed as a target, which can be an object, a compound of objects, or a binary. In a further embodiment, the payload may comprise a verb which describes a relationship between a subject and a target, where the relationship can be an object or a compound of objects. In yet another embodiment, the verb may never comprise a binary. A claim may have a claim type, just as edges have edge types. For example, a claim that a user currently lives in San Francisco has a claim type of current city. The claim type may be assigned as a metadata object by the social networking system  100 . 
     As illustrated in a high-level block diagram depicted in  FIG. 1B , a claim object  116  may be represented as a data structure that includes an author agent  118 , an assertion  120  that may further include a subject  122 , a verb  124 , and/or a target  126 , an owner agent  128 , copyrights  132  that may further include a user-payload bit  134  and an application-copyright bit  136 , audience agent(s)  130 , a use right bit  138 , and metadata object(s)  140 . A viewing agent  142  may be represented in the social networking system  100  as an object  148  and may be associated with a user device  144 . Applications  146  may be authorized by a viewing agent  142  to author claims on behalf of the viewing agent  142 . As depicted in  FIG. 1B , a claim object  116  may include an assertion  120  that includes a target  126  that stores content in binaries  150  or as one or more objects  148 . 
     A claim object  116  may be created by an author agent  118 , read by an audience agent  130 , synced by the social networking system  100  to any device or service with which the social networking system  100  has a relationship or can guarantee will not break the privacy model, payload-copied by any audience agent  130  conditional to the copyrights  132  where being payload-copied creates a new claim under the audience agent&#39;s authorship with the payload as the target, and deleted by the owner agent  128  or by the author agent  118  in the case that the author agent  118  is an audience agent  130  (where the author agent  118  “can see” the claim  116 ). A claim object  116  may have an assertion  120  that is updated by the author agent  118 , creating a new claim that copies all of the other claim fields, and updates all reference to the old claim to point at the new one. The privacy of a claim  116 , or the selection of audience agents  130  that may view the claim  116 , may be updated by the owner agent  128  of the claim  116 . Similarly, the copyrights  132  of a claim may be updated by the owner agent  128  of the claim  116 , changing the ability of audience agents  130  and applications  146  working on behalf of audience agents  130  to “copy” the payload of the claim  116 . The payload of the claim  116  may also be described as the assertion  120  of the claim object  116 , in one embodiment. In addition, the use right bit  138  of a claim  116  may be updated by the owner agent  128  of the claim  116 , changing the ability for the claim  116  to be “boosted” in search results or other claim ranking algorithms. 
     Each of the above claims in the aforementioned examples may or may not be factually true, and the actual truth may not be knowable or even exist. Moreover, different users will have a different measure of the truth of an assertion in a claim based on the information known to the user. To address the subjective nature of claims, the social networking system may gather information related to the claim from other objects on the social networking system. In effect, the social networking system  100  may determine one or more “truth coefficients” for a claim object  116  based on information about a viewing agent  142 , the author agent  118 , the owner agent  128 , and/or the audience agents  130  of the claim object  116 . The one or more truth coefficients may be stored as metadata objects  140  by the social networking system  100  for the claim object  116 . Embodiments for evaluating claims and using the evaluated claims to provide information to users are described below in further detail in the description of  FIGS. 2-5 . 
     Components of a Claim 
     As illustrated in  FIG. 1B , the social networking system  100  includes a warehouse layer  182  and a claim layer  184 . The warehouse layer  182  is comprised of objects  148  and binaries  150 , providing foundational services that are not directly usable by users of the social networking system  100 . Objects  148  have unique identifiers/uniform resource identifiers, are not owned, can be created and referenced by the claim layer, and cannot be destroyed. Binaries  150 , or binary storage, comprise “blobs” or files, such as photos, video, text, and the like. Binaries  150  are not owned and cannot be directly put into the social networking system  100 . Binaries  150  are created as the target  126  of a claim  116 . Binaries  150  cannot be referenced directly and can only be referenced via the claim layer. 
     The claim layer  184  of the social networking system  100  sits on top of the warehouse layer  182  and serves as the interface down to the storage/object model of the warehouse layer  182 . The claim layer  184  of the social networking system  100  provides an identity model for items stored in the warehouse layer  182  and provides processes for validating actions on the warehouse layer  182 . Other services of the social networking system  100 , such as the social graph of nodes and edges discussed above, may fit on top of the claim layer  184 . 
     In one embodiment, the entire claim structure can be stored as an object on a social graph and associated with a unique URL or identifier. The claim data structure can be created, read, updated, synched, payload copied, or deleted by its author agent  118 . In one embodiment, the general form of a claim is: CLAIM (Author|Assertion (Subject, Verb, Target)|Owner|Audience|Copyrights (User-Payload, Application)|Use Rights|Metadata). 
     In one example, a claim in a social networking system may include any user generated content, such as a status update, photo, video, link, message, or comment. In another example, a claim in a social networking system  100  may include any action or connection with an object in a social graph whether the object is on or off the social networking system  100 , such as liking a product on an e-commerce website external to the social networking system  100 , listening to a record album through an external music streaming application, reading a book on a electronic book reading application and/or device, playing a game operating on the social networking system  100 , and so forth. 
     In yet another example, “friending” or forming a connection between two agents, users, entities, or nodes in the social graph can be described as a claim that an initiating agent is “friends with” the target agent. The privacy of that claim may be limited to the initiating agent and the target agent unless the claim is reciprocated by the target agent. “Friend lists” may be generated by agents that may be structured as claims in the social networking system  100 . If, from the perspective of a viewing agent  142  of the social networking system  100 , one cannot see an author agent&#39;s  118  friend list but can see another agent&#39;s claim of friendship with the author agent  118 , then they may implicitly see the friendship-relationship. If one cannot see a friendship via any friend list, they may still be able to view actions taken on the social networking system  100  through regular privacy settings that may imply friendship. In one embodiment, an application may read claims to which it has access and re-create a derivative friend list that approximates what it can see of an author agent&#39;s  118  friend list. 
     Author Agents and Owner Agents of Claims 
     An agent may be a user of the social networking system  100  having a user profile that represents a person in the real world, an entity of the social networking system  100  having an entity profile that represents a corporation, business, celebrity, or place in the real world, an application operating on or outside of the social networking system  100  which may include third party applications that may connect to the social networking system  100  from an external system or website, a page on the social networking system  100 , a group of users on the social networking system  100  in which a designated administrator acts on behalf of the group, or an event on the social networking system  100  in which a designated administrator acts on behalf of the event. In one embodiment, the social networking system  100  has validated that an agent accurately represents a person or an entity in the real world. A viewing agent  142  may author claims, or write claims to the social graph. A viewing agent  142  may also read or view claims that are accessible to the viewing agent  142  on the social graph based on whether the viewing agent  142  is designated as an audience agent  130  of the claim  116 . Agents may also be created or destroyed by the social networking system  100  at will. A viewing agent  142  may also access and interact with claims through other methods of communication, such as audio and voice commands. 
     In one embodiment, special classes of agents may be defined for kids and minors, or users under the age of majority. These classes of agents may have explicitly limited authoring privileges on the social networking system  100 , such as not being able to author claims to an audience that includes all users of the social networking system  100  or publicly available claims. In other embodiments, these classes of agents may have implicit limitations on authoring privileges, such as enabling them to choose a publicly available audience but limiting the privacy of those claims until they reach the age of majority. Additionally, a kid is initially connected to a parent, another user on the social networking system  100  and cannot “unfriend,” or sever the connection to, the parent. A parent can recover a kid&#39;s password, may be able to turn off any feature which a kid has access except those where the parent can view the kid&#39;s actions, and may also view inbound friend requests such that the audience of an inbound friend request to a kid is the kid and the parent. Furthermore, agents are limited in their ability to tag minors and kids, such as suggesting that content be placed on the timeline of minors and kids unless they are at least friends of friends of the minor. Minors and kids may also be excluded from the audience of certain agents by another agent of the social networking system  100 , such as a parent of the minor(s), or the social networking system  100  acting as an agent. 
     Agents may also block other agents, which prevents the other agents from including the blocking agent in an audience of claims owned by the other agents and prevents other agents from being included in the audience of claims owned by the blocking agent. Agents may also run “browse” queries, or queries run on claims in the social networking system  100  to return “best match” and “exact match” search results. Viewing agents  142  may also delegate capabilities to applications  146 , giving the applications  146  permissions to exercise any of the capabilities that the applications  146  have, such as authoring claims on behalf of the viewing agents  142  and generating derivative claims based on the authorized authored claims. 
     Agents may be author agents  118 , owner agents  128 , and audience agents  130 . An author agent  118  of a claim object  116  may, by default, be designated as the owner agent  128  of the claim  116  and be included as an audience agent  130 , in one embodiment. For example, a user of a mobile application for an address book may want to record the phone number of a connected user with a privacy setting set to “only me,” meaning that the user would like to keep the phone number private and accessible only to herself. A claim object  116  describing this claim of a phone number for a connected user may, by default according to the privacy settings configured by the user, designate the user as the author agent  118 , owner agent  128 , and audience agent  130  of the claim object  116  for the private phone number of the connected user. Through various interfaces, such as an user interface on the social networking system  100  or through one or more application programming interfaces (APIs), an author agent  118  may designate an owner agent  128  and one or more audience agents  130 . Privacy control settings may be imported by the social networking system  100  to select the one or more audience agents  130  for a claim object  116 , in one embodiment. Copyright and use rights preferences may also be predetermined by author agents  118  through preference settings configured in the social networking system  100  and imported by default into claim objects  116  generated by the author agents  118 , in one embodiment. 
     In one embodiment, an author agent  118  may view claim objects  116  that have been authored by the author agent  118  from the perspective of a specific viewing agent  142  in the social networking system  100 . For example, through a user interface, the author agent  118  may input the specific viewing agent  142  to view which claim objects  116 , if any, are viewable by the specific viewing agent  142  based on whether the specific viewing agent  142  is included as an audience agent  130  of a claim object  116  written by the author agent  118 . In another embodiment, an audience agent  130  may view a claim object  116  and copy the claim to another location, such as the timeline of the audience agent  130 , the timeline of an agent connected to the audience agent  130 , a message to a target agent, a communication external to the social networking system  100 , or on a website external to the social networking system  100 . In this way, the audience of the claim object  116  may be expanded to include a new audience as determined by the audience agent  130  copying the claim object  116 . 
     In another embodiment, viewing agents  142  and applications  146  acting on behalf of agents may run queries over a set of claims. Because claims are structured (i.e., have structured data), the social networking system  100  may execute structured queries on a set of claim object  116  with relative ease. Queries may be executed through various interfaces with the social networking system  100 , such as a user interface on the social networking system  100 , a set of application programming interfaces (APIs), and as a search function included in other processes. 
     Author Agents 
     In a social networking system  100 , an “author” may include any agent that has been given abilities to act in the social networking system  100  and that may carry a truthfulness score, truth coefficient, and/or reputation score. An author agent  118  is an “author” of a claim such that the assertion  120  of the claim object  116  is written by the author agent  118 . The author agent  118  may write the assertion  120  of the claim object  116  being authored through one or more interfaces with the social networking system  100  as well as external systems connected to the social networking system  100 , such as third party applications authorized to author claims on behalf of the author agent  118 . An author agent  118  may also make derivative claims, or claims based on other claims in the social networking system  100 . For example, a first author may claim that a second author claims that the second author&#39;s phone number is 867-5309. In one embodiment, the social networking system  100  may act as an author agent  118  in making derivative claims based on claims made by other agents in the social networking system  100 . 
     An author agent  118  has the right to access all claims that the author agent  118  has made that they can see, in one embodiment, by accessing an activity log or a download of all claims data. In further embodiments, a business model for a pay-per-write/read model may implemented using claim objects  116  in the social networking system  100 . An identity marketplace could charge for access to specific claims by type (or allow others to input their claims and charge for access to their information). For example, a social networking system may enable applications to pay monthly or per claim for access to read claims by a particular agent or an agent associated with a particular application or demographic. The identify marketplace or exchange of information for payment would only occur with the agents&#39; or users&#39; knowledge and permission. 
     Owner Agents 
     In one embodiment, each claim may have one owner agent  128 . An author agent  118  of a claim object  116  is, by default, the owner agent  128 , except for applications  146  authoring claims on behalf of a particular agent. In that case, the particular agent is the owner agent  128  of claims authored by the applications  146  authorized to author claims on its behalf. An author agent  118  may designate an owner agent  128  of a claim object  116  authored by the author agent  118 . An owner agent  128  also determines an audience of a claim, where the audience comprises one or more audience agents  130 . An owner agent  128  of a claim object  116  may specify settings for the claim object  116 , such as the use-right bit  138 , copyrights  132  including the user-payload-copyright bit  134  and the application-copyright bit  136 . The owner agent  128  of the claim object  116  may also delete the claim, including any uploaded content, or payload, of the claim. By deleting the claim, the binaries associated with the content in the payload of the claim will be swept by the social networking system  100  and the references by the claim to the associated binaries will be deleted. 
     Ownership of a comment on a claim, such as a photo, is automatically transferred to the owner of the binary claim and audience. For example, a first author that uploads a photo to the social networking system  100  and a second author generates a comment on the photo, describing the photo as a wonderful shot. The second author&#39;s comment is a claim that is now owned by the first author of the original binary claim that includes the uploaded photo as well as the audience for the original binary claim. 
     Applications 
     An application  146  may be authorized to author claims on behalf of an agent, in one embodiment. As a result, the authorized application may be an author agent  118  in the social networking system  100  that assigns ownership of the claim to the authorizing agent such that the authorizing agent is the owner agent  128  of the claim object  116  authored by the authorized application. For example, gaming applications such as Cityville and Castleville may be connected to or operate on the social networking system  100 , enabling agents on the social networking system  100  to play the games through the social networking system  100 . The agents playing the games may authorize the gaming applications to author claims on behalf of the agents, such as publishing claims of reaching achievements in the game and generating derivative claims that the gaming agents enjoy playing casual games based on the claims that they played the gaming applications. 
     Applications  146  are systems to which any agents may delegate any or all of their capabilities. Applications  146  can request permissions from agents to act on their behalf in various forms. Applications  146  may request permissions to read all claims made by an agent, read only claims having a minimum privacy level, or read all claims of a specific application. Applications  146  may also request permissions to write claims with an audience that only includes the authorizing agent, permissions to write claims with an audience correlating to a specific privacy level, such as a privacy control setting predetermined by the authorizing agent, and request a one-time extra permission to write a specific claim and/or story. Applications  146  may also be given permission to perform any action an agent may perform on the social networking system  100 . Applications  146  are registered on the social networking system  100  and follow documented application programming interfaces. An agent can revoke an application&#39;s permission at any time. An agent may specify which applications may have access to their data in any fashion. 
     Assertions: Content of Claims 
     Claims may include different types of assertions that include content in a social networking system  100 . A claim  116  may include an assertion  120  that comprises any content of any size represented in the social networking system as a content object, from a bit indicating that a sensor in a fridge has detected that the fridge is empty to a high resolution photo uploaded from a mobile device with embedded geographic location data that has been tagged with one or more agents on the social networking system  100 . Each claim  116  includes an assertion  120  that includes a “payload” of content that is written to the social graph. The payload of content is the core of an assertion. Payloads of claims may vary depending on the claim type. For example, a user claiming a relationship status with another user on the social networking system, such as engaged, is a claim in which the payload of the claim is that the users are engaged. Other types of claims include claiming a connection with another user on the social networking system, declaring an interest in a user profile on the social networking system, checking in other users at a location, tagging users in work experience or education experience, tagging agents in a photo or video, and tagging agents in a status message. The author agent  118  in the fridge example is an application connected to the sensor in the fridge that is an agent in the social networking system  100 . 
     Additional types of claims may include declaring user profile information, declaring expertise and/or skills for a user, recommending a product and/or service represented by a page on the social networking system  100 , tagging a content object, such as a photo, video, or status message, with a link to one or more users of the social networking system  100 , tagging a check-in object that includes a geographic location with one or more users of the social networking system  100 , a page and/or application representing a business or entity making a claim about one or more users of the social networking system  100  having performed a custom graph action on a custom graph object, and a user making an appointment or scheduling an event with one or more other users using a calendaring application on the social networking system  100 . In other words, a claim may include an assertion about any content that may be stored and/or shared on a social networking system  100 . 
     An assertion  120  of a claim comprises a subject  122 , a verb  124 , and a target  126 , in one embodiment. In one embodiment, the payload may be formed as a subject which is an object the assertion is describing. In another embodiment, the payload may be formed as a target, which can be an object, a compound of objects, or a binary. In a further embodiment, the payload may comprise a verb which describes a relationship between a subject and a target, where the relationship can be an object or a compound of objects. 
     The payload of a claim may include any type of content, including structured and unstructured content. The payload of a claim may include structured elements along with structured content, such as “Michael is listening to Lady Gaga with John on Spotify.” The “listening” action is a custom graph action, and the preposition “with” is a structured element that indicates another agent is performing the custom graph action with the author agent  118  of the claim. Structured content in this example includes “Michael” and “John,” agents of the social networking system  100 , “Lady Gaga,” a custom graph object such as an artist object that may included structured information, such as the birth year of the artist and the genre of the artist, as well as connections to other custom graph objects, such as album objects representing albums recorded by the artist and song objects representing songs recorded by the artist. An application  146  authoring the claim on behalf of an agent, such as “Spotify” authoring the claim on behalf of the agent “Michael,” is another example of structured content within the payload of the claim. 
     Another type of claim is a negative claim, such as a first user removing a tag from a photo uploaded and tagged by a second user. The tag by the second user is a claim in conflict with the removal of the tag by the first user. The assertion, in that case, is whether the first user is pictured in the photo uploaded by the second user. When an agent tags himself, herself, or itself and/or other agents in a social networking system  100 , the tag represents a claim including an assertion being made to an audience. For example, a page on the social networking system  100  representing a college may make a content post comprising a photo taken on campus. The administrator of the page, a designated user of the social networking system  100 , may tag a current student of the college, another user of the social networking system  100 , in the post on behalf of the entity, the college&#39;s page. In this way, the entity has made a claim that the college student user is pictured in the photo posted by the page. Other types of claims, aside from posts of photos, videos, status, links, and messages, feedback from other users that includes comments and “likes,” and actions such as tagging, “liking,” wanting, listening, and other custom graph actions, includes sets determined by an agent, such as lists, albums, and maps of favorite places. 
     In this example, the application  146  authoring the claim  116  on behalf of the agent “Michael” includes functionality that recognizes that Michael listened to music by Lady Gaga in conjunction with John. A user device  144  associated with the agent “Michael” operated the “Spotify” application  146  to perform the custom graph action of “listen” in conjunction with the agent “John” who, on a separate user device  144  associated with him, operated the same application  146  to perform the custom graph action of “listen” on one or more custom graph objects that represents songs by a custom graph object that represents the artist Lady Gaga. In one embodiment, the payload of the claim object  116  may include links to each object  148  included in the payload, such as links to user profile objects for “Michael” and “John,” a link to the custom graph object for “Lady Gaga,” which may link to an entity profile object for Lady Gaga on the social networking system, as well as a page object for the “Spotify” application  146  authoring the claim  116 . Structured information is defined on the social graph by capturing interactions by agents with objects on the social networking system  100 , in one embodiment. For example, social validation and/or feedback on a posted content item, such as likes, comments, and shares, may be captured to provide structured information about the content item as well as author agents  118  of the content item, likes, comments, and shares. User interactions that occur on systems external to the social networking system  100 , such as on external websites and applications, may be structured using custom graph objects and custom graph actions defined and implemented by the external systems in sharing information with the social networking system  100 . By storing claims in a structured way, the social networking system  100  may provide sophisticated features, such as measuring a particular agent&#39;s interest in Lady Gaga based on number of listens using streaming music applications  146  such as Spotify, determining levels of a particular agent&#39;s influence amongst connected agents, receptiveness to advertising based on user feedback of claims that have been boosted by advertisers, and so on. The effect of structuring a social graph on top of claims, using nodes and edges that further comprise claim objects, provides the social networking system  100  with more granularity of detail in analyzing, aggregating, and interpreting information obtained about agents. 
     The payload of a claim may also include unstructured data, such as the amount of time spent viewing photos posted by an agent and metadata included in other claims. Unstructured data may include any data that is not structured in the social networking system  100 . The payload for a claim may also include hyper-links to anything on the Internet, including timelines of other agents. A tag, or a special case of a hyper-link to target agents, may also be included in a payload of a claim because a tag is an active suggestion by the author of the claim that the content of the claim be presented on the timeline of the tagged agent. In one embodiment, the payload includes text, media, references and/or links to objects  148  in the social networking system, applications  146 , other claims, agents, and any combination thereof. A claim object  116  may include an assertion  120  that includes a subject  122 , a verb  124 , and a target  126 . These components of an assertion  120  are described in further detail below. 
     Subject 
     The subject  122  of an assertion  120  comprises an object  148  that the assertion  120  is describing. For example, a claim object  116  may represent a check-in event made by a user that he is at the Eiffel Tower in Paris. The claim may include a photo of the view from the Eiffel Tower snapped by a mobile device associated with the user. The user may create a check-in event using an application operating on the mobile device that is connected with the social networking system  100  and tag the photo with himself and a connected user. In this example, multiple claim objects  116  may be generated by the user, each having different assertions  120  and subjects  122 . One claim  116  may include an assertion  120  that the user is located at the Eiffel Tower in Paris. In that claim, the subject  122  of the claim  116  is the user&#39;s current location that is stored in an object  148  in the warehouse layer of the social networking system  100 . 
     Two other claims  116  may include assertions  120  that the photo depicts the user and the connected user as tagged by the user. The subject  122  of one of the claims comprises the user being depicted in the photo. The subject  122  of the second claim comprises the connected user being depicted in the photo. For each of these two claims, the subject  122  of the assertion  120  is a user profile object in the social networking system  100 , an object  148  in the warehouse layer of the social networking system  100 . 
     As another example, an application may author a claim, on behalf of an agent, that reads “Michael listened to Lady Gaga on Spotify.” A claim  116  may be generated with an assertion  120  that includes the subject  122  of “Michael,” an agent in the social networking system  100  represented by an object  148  in the warehouse layer, because the claim is about Michael listening to Lady Gaga. In another embodiment, another claim  116  may be generated with an assertion  120  that includes the subject  122  of “Lady Gaga,” another agent in the social networking system  100  represented by a different object  148  in the warehouse layer, because that claim is about Lady Gaga being listened to by an agent. In a further embodiment, yet another claim  116  may be generated with an assertion  120  that include the subject  122  of the exact song listened to by Michael, represented by a custom graph object. 
     In another embodiment, a claim object  116  may include an assertion  120  that only includes a subject  122  and a verb  124 . For example, a user may declare on the social networking system  100  to be born on Mar. 15, 2011. One claim that may be generated from that self-declaration includes an assertion  120  formed by the subject  122  that includes the user making the self-declaration, represented by an object  148  and a verb  124  that includes a reserved verb “IsPerson” that signifies that the user is a person. In that case, the target  126  of the claim is also the user declaring to be born on Mar. 15, 2011. The target  126  in that claim points to the user profile object for the user, an object  148  in the social networking system  100 . 
     Verb 
     A verb  124  in an assertion  120  of a claim  116  describes the relationship between the subject  122  and the target  126  in the assertion  120 . A verb  124  may comprise an object  148  or an object  148  that is a compound of objects. In one embodiment, the verb  124  of an assertion  120  of a claim  116  is never stored as a binary  150  in the warehouse layer of the social networking system  100 . Returning to the example where the user tagged a photo of the view from the Eiffel Tower with a tag of himself and a connected user, the subject  122  of the assertion  120  in the claim object  116  may include the other user tagged in the check-in event and the verb  124  of the assertion  120  in the claim object  116  may include a reserved verb such as “IsWith.” The user may also tag a face in the uploaded photo as the tagged user. In this case, the user is claiming that the uploaded photo depicts the tagged user such that the verb  124  of the assertion  120  in the separate claim object  116  includes a different reserved verb such as “IsTaggedInPhoto,” for example. The social networking system  100  may have reserved verbs that describe actions that may be taken in the social networking system  100 , such as “HasPhoto(s),” “HasText,” “Commented on &lt;OBJ-ID&gt;,” “Liked,” “AT,” “HasName,” “HasMember,” “NameIS,” “FriendsWith,” “HasPhotoSameAs,” and the like. 
     Returning to the example in which an application may author a claim on behalf of an agent, a claim that reads “Michael listened to Lady Gaga on Spotify,” the verb  124  is “listened,” the target  126  is “Lady Gaga,” the author agent  118  is the application “Spotify,” and the owner agent  128  is the agent “Michael” represented by an object  148  in the warehouse layer, in one embodiment. The custom graph action “listen,” stored as an object  148  in the warehouse layer, is designated as the verb  124  of the assertion  120  of that claim  116 . In this way, claims may be generated using custom graph actions and custom graph objects in addition to reserved actions (verbs) and other objects  148  in the social networking system  100 . 
     Target 
     A target  126  of an assertion  120  of a claim object  116  may comprise an object  148 , a binary  150 , or a compound of objects  148  which is an object  148 . The target  126  of an assertion  120  of a claim  116  represents content that is related to the subject  122 . Returning to the above example, the custom graph object “Lady Gaga” is stored as the target  126  of the assertion  120  for the claim object  116 . As a result, the target  126  of that claim points to an object  148 , specifically a custom graph object for “Lady Gaga,” an artist object stored as an object  148  in the social networking system  100 , in one embodiment. In another embodiment, “Lady Gaga” may be an agent in the social networking system  100 , stored as another object  148  in the warehouse layer. 
     Returning to the example above in which a user uploads a photo at the Eiffel Tower, the photo, the location coordinates uploaded by the mobile device, and text written by the user may be stored in binaries  150  as the payload, which includes a target  126 , of the assertion  120 . A claim object  116  may also include an assertion  120  that includes a subject  122  and a verb  124  that are stored as objects  148 . Returning to the example, the user uploading a photo of the view from the Eiffel Tower may also tag himself with another user of the social networking system  100 . In that case, the user is claiming that he is with the other user at the Eiffel Tower. 
     In a further embodiment, a claim object  116  may include an assertion  120  that only specifies a target  126 . For example, a claim object  116  may include an assertion  120  that includes a target  126  that points to a compound of objects, including older claim objects  116 , about a topic in the social networking system  100 , such as Whitney Houston. In that case, the claim object  116  that only specifies a target  126  to a compound of objects may copy the subject  122  of the compound of objects, Whitney Houston, as the subject  122  for the claim. For example, the compound of objects may be a group of songs performed by the artist Whitney Houston and purchased by other users of the social networking system  100 . 
     All activity that occurs on the social networking system  100  and activity operating outside of the social networking system that is reported through applications may be described using claim objects  116  that have assertions  120  which include targets  126 . Posts, including messages, may be described as claims with payload targets. For example, a status update post, which includes text written by an agent, may be stored as a claim object  116  owned and authored by the agent writing the status update post having an assertion  120  that includes a subject  122  that references the object  148  of the status update, a verb  124  of “HasText,” and a target  126  that references a binary  150  associated with the text. Similarly, a photo upload post, which includes a digital photo uploaded to the social networking system  100  by an agent, may be described as a claim object  116  owned and authored by the agent uploading the photo having an assertion  120  that includes a subject  122  that references the object  148  of the photo, a verb  124  of “HasPhoto,” and a target  126  that references a binary  150  associated with the photo. 
     An application making a post on behalf of an agent, such as “Sam” on a social networking system  100  may be described in a claim object  116  in which the author agent  118  is “Sam: ViaApp” and an assertion  120  having a subject  122  that points to the object  148  for the photo, a verb  124  of “HasPhoto,” and a target  126  of a binary  150  on the social networking system  100 . An application making a post on behalf of the same agent “Sam” on a system external to the social networking system  100  may be described in a similar claim object  116  in which the author agent  118  is “Sam: ViaApp” and an assertion  120  having a subject  122  that points to the object  148  for the photo, a verb  124  of “HasPhoto,” except where the target  126  of the claim object  116  includes a link to an external binary. 
     A comment on a post may be stored as a claim object  116  having an assertion  120  in which the commenting agent is the subject  122 , the verb  124  being “Commented on &lt;OBJ-ID&gt;” and the target  126  being the binary  150  of the object  148  stored at &lt;OBJ-ID&gt; in the warehouse layer of the social networking system  100 . In making the comment on the post, the commenting agent transfers ownership of the post to the owner of the binary claim. As a result, the claim object  116  representing the comment has the owner agent  128  as the owner of the &lt;OBJ-ID&gt;. 
     Edges may be described as claims with targets that only point to objects  148  on the social networking system  100 . For example, if an author agent  118  named “Paul” uploaded a photo onto the social networking system  100 , another author agent  118  named “Sam” may click on a link to “like” the photo, or express approval and/or interest in the photo. A claim object  116  for Paul&#39;s claim may include an assertion  120  having a subject  122  of the object  148  of the photo, a verb  124  of “HasPhoto,” and a target  126  of the binary  150  associated with the photo. A claim object  116  for Sam&#39;s claim that he liked Paul&#39;s photo may include an assertion  120  having a subject  122  of an object  148  associated with Sam, a verb  124  of “Liked,” and a target  126  pointing to an identifier of the object  148  of Paul&#39;s claim. The claim object  116  for Sam&#39;s claim that he liked Paul&#39;s photo includes the same privacy setting of Paul&#39;s claim, importing the listing of audience agents  130  from Paul&#39;s claim into Sam&#39;s claim. 
     Another type of edge includes a comment on a content item posted on the social networking system  100 . Continuing the example above, where Paul posted a photo to the social networking system  100  and set the privacy of that claim to Paul&#39;s friends on the social networking system  100 , two claim objects  116  may be generated based on a comment by Sam on Paul&#39;s photo. One claim object  116  may include an assertion  120  that includes a subject  122  that points to an object  148  representing Sam as an agent in the social networking system  100 , a verb  124  of “CommentedOn,” and a target  126  of the object  148  for Paul&#39;s photo. That claim object  116  may have the owner agent  128  set to the owner of the claim object  116  for Paul&#39;s photo and have the privacy imported from that same claim object  116  for Paul&#39;s photo. Another claim object  116  may include an assertion  120  that includes a subject  122  that points to the object  148  representing the first claim object  116  for Sam&#39;s comment on Paul&#39;s photo, a verb  124  of “HasText,” and a target  126  that points to the binary  150  that stores the comment posted by Sam. Additionally, an edge may include a “like” of a comment on a content item on the social networking system  100 . A claim object  116  that describes that type of edge may include an assertion  120  that includes a subject  122  that points to the object  148  for Sam as an agent on the social networking system  100 , a verb  124  of “Liked,” a reserved verb in the social networking system  100 , and a target  126  pointing to an identifier of the binary  150  for the comment. 
     Another type of edge in the social networking system  100  may include a check-in event, or any post in the social networking system  100  that includes a location such as a status update, a photo upload, a video upload, an event, and the like. A claim object  116  for that type of edge may include an assertion  120  that includes a subject  122  that points to an object  148  for Sam as an agent of the social networking system  100 , a verb  124  of “AT” which indicates being located at a place, and a target  126  that points to an object  148  for a particular location, such as “Nuthouse,” a dive bar in Palo Alto, Calif. A metadata object  140  may be associated with that claim object  116  that includes the latitude and longitude of the check-in event received from the user device associated with the agent Sam. 
     Another type of edge may be generated by an agent of a social networking system  100  that indicates that a certain object is the same as another object in the social networking system  100 , such as duplicative pages for fans of Justin Bieber. In one embodiment, an agent of a social networking system  100  may provide information to the social networking system  100  indicating that one or more objects are equivalent. In that case, the claim object  116  for that action would include an assertion  120  that includes a subject  122  that points to the first object  148 , a verb  124  of “IS” that indicates equivalence, and a target  126  that point to the second object  148 . 
     Lists may be generated by an agent on the social networking system  100 , such as organizing lists of audience agents  130 , lists of favorite restaurants, lists of favorite topics, and so on. A generated list may be described as a claim object  116  that includes an assertion  120  having a subject  122  that points to the object  148  for the list, a verb  124  of “HasName” that indicates that the list has a name, and a target  126  pointing to the name of the list as stored as an object  148 . Another claim object  116  for a list may include an assertion  120  having a subject  122  that points to the object  148  for the list, a verb  124  of “HasMember” that indicates that the list has a member, and a target  126  pointing to the object  148  for the agent that is included in the list, for example. In one embodiment, a list may be described as a name payload and a set of edges in the social networking system  100 . In another embodiment, an application  146  may be used to generate lists on the social networking system  100 , generating multiple claim objects  116 . A first claim object  116  describing a claim of a list generated by an application  146  may include an assertion  120  that includes a subject  122  that points to the object  148  representing the list, a verb  124  of “NameIS” that indicates the name of the list, and a target  126  that points to the identifier of the path of the object created by the application  146 . A second claim object  116  describing a claim of a list generated by an application  146  may include an assertion  120  that includes a subject  122  that points to the object  148  representing the list, a verb  124  of “HasMember” that indicates the list includes a member, and a target  126  of an object  148  representing an agent that is included in the list. 
     Friendship, or users connecting with each other on the social networking system, may be described as a reserved verb of reciprocated claims authored by the users connecting with each other. Suppose Sam requests to be friends with Paul on the social networking system  100 . A friendship request may be captured as a claim object  116  in the social networking system  100 , such that the claim object  116  includes an assertion  120  having a subject  122  that points to the object  148  representing the requesting agent, Sam, a verb  124  of “friends with” that indicates a claim of being friends with another agent, and a target  126  that points to the object  148  the target agent, Paul. A notification of the friendship request may be in the form of a browse query, or a query of all claims, in which a search term includes claims that have the verb “friends with” and the target of the object  148  representing Paul, the target agent. Paul may then accept the friendship request from Sam which may be captured as another claim object  116  that has an assertion  120  that includes a subject  122  pointing to the object  148  for Paul, a verb  124  of “friends with” and a target  126  pointing to the object  148  for Sam. The visibility, accessibility, or audience of the friendship request is set, by default, to only include the requesting agent and the target agent until the friendship request is accepted, making the claims of friendship reciprocal. Reciprocal claims of friendship may be public or limited to the privacy settings of the requester and/or target agent. 
     An agent may request to boost a story and/or search results of a query for stories referencing a topic, such as running. This request may be described as a claim using a reserved verb for copying a payload of an original claim and boosting the original claim. For example, a claim object  116  for boosting a specific claim may include an assertion  120  having a subject  122  pointing to an object  148  for the agent requesting the boost, a verb  124  of “pays &lt;X&gt; to boost” where &lt;X&gt; represents a fee negotiated by the social networking system  100  to boost the claim, and a target  126  pointing to the object  148  of the claim that is to be boosted. Similarly, a claim object  116  for boosting the search results of a query referencing a topic may include an assertion  120  having a subject  122  pointing to an object  148  for the agent requesting the boost, a verb  124  of “pays &lt;X&gt; to boost” and a target  126  referencing an object  148  representing the search results of the browse query. 
     Audiences: Context of Claims 
     An audience is a context in which a claim is made. An agent may make a claim about other agents, such as “Bob is a good cook!” and “Joe likes cooking.” The author agent  118  may control the size of the audience of this claim by designating audience agents  130  that comprise the audience, such as making this claim accessible to the public (including both users and non-users of the social networking system), to a certain group of connected agents, to the subject agent&#39;s connections, or only to selected agents. In another embodiment, an audience may be determined by the social networking system  100  based on the agents selected to receive the claim. For example, a first agent may send a message to a second agent stating that a third agent is a good cook on the social networking system  100 . Because the third agent is not included in the audience of the claim made by the first agent, the third agent may not view the claim made by the first agent. 
     One or more audience agents  130  may be set by an owner agent  128  of a claim  116 . An audience agent  130  is an agent of the social networking system  100 , represented by an object  148  in the warehouse layer of the social networking system  100 , that can access, or view, the claim&#39;s authorship, ownership, audience, assertion, and/or copyrights. An owner agent  128  may define a set of agents to be audience agents  130  as part of one or more privacy settings, or privacy control settings, configured in the social networking system  100 . The social networking system  100 , acting as an agent, is included as an audience agent  130  in every claim object  116  on the social networking system  100 . An author agent  118  of a claim object  116  has the right to access all claims they have made that they can see, meaning any claim in which the author agent  118  has been designated as an audience agent  130  of the claim. All agents have the right of access made about them that they can see. Interfaces may be provided on the social networking system  100  to access this information, such as a user interface that provides for display the accessible claims on the social networking system  100  and an application for downloading the accessible claims information. A claim may also be deleted by an owner agent  128  that controls the audience of the claim. An author of a claim may delete the claim if the author is part of the audience of the claim. Deleting a claim will remove the claim from the social networking system in a reasonable amount of time, making the claim inaccessible. 
     Audience agents  130  may be selected by an owner agent  128  through various methods, such as in-line selection, pre-selection, delegation, and at-will limitation by the social networking system  100 . In-line selection refers to the owner agent  128  can select an audience at the time of posting the claim  116 , where the owner agent  128  is also the author agent  118  of the claim  116 . Pre-selection refers to the owner agent  128  pre-selecting an audience, such as determining a privacy list of agents to be included in the audience, where the owner agent  128  is also the author agent  118  of the claim  116 . Delegation refers to the instance where the owner agent  128  is not the author agent  118  in which the author agent  118  designates the owner agent  128  and the audience agent(s)  130  must be pre-selected by the owner agent  128 . The social networking system  100  may also limit the ability and/or options of a given agent to make claims in any way, such as by limiting the audience agents  130  of claims  116  authored by minor agents. In another embodiment, the audience of a claim may be a direct enumeration of agents or a reference to a pre-defined list of agents. In a further embodiment, the mode of audience selection (in-line, pre-selection, and delegation) may be defined in the product interface of the social networking system  100 . 
     Copyrights, Use Rights, and Metadata Objects 
     As mentioned above, an owner agent  128  of a claim object  116  may specify settings for the claim object  116 , such as the use-right bit  138 , copyrights  132  including the user-payload-copyright bit  134  and the application-copyright bit  136 . These bits help define the audience of the claim and the permissions of the audience to copy claims into new claims. Note that the social networking system may synchronize claims to other devices and/or services connected to the social networking system  100  regardless of the copyrights  132  set by the owner agent  128  without compromising the privacy model of the social networking system  100 . The social networking system  100  is not limited by the one or more copyrights  132  defined by the owner agent  128  for synchronizing the content stored on the binaries, such as copying a claim, caching, device syncing, and the like to provide better an enhanced user experience on the social networking system  100 . The copyrights  132  of a claim object  116  pertain to the permissions of audience agents  130  to copy an assertion  120  included in the claim object  116  into a new claim object  116 . 
     User-Payload-Copyright Bit 
     Content within a claim object  116  may be “owned” by an owner agent  128  in the sense that the owner agent  128  may control how the content is distributed and is accessed by other agents in the social networking system  100  as well as in systems external to the social networking system  100 . For example, an author agent  118  may upload a video from a mobile device to the social networking system  100 . The social networking system  100  enables agents to store content, such as video, pictures, and the like, by providing binaries used for storage. When a content item is uploaded, an object  148  is generated in the social networking system  100 , in one embodiment. In another embodiment, the content item is stored in the binaries  150  as created by being a target  126  of the assertion  120  of the claim object  116 . The claim object  116  that is generated may include one or more copyright bits to enable the owner of the content included in the claim object  116  to determine the ways in which the claim may be copied. A user-payload-copyright bit  134  controls if a user can copy the binary  150  of a claim  116  into a new claim. The ‘binary’ of a claim includes the non-referenceable storage provided by the social networking system  100  to store the uploaded content. For example, if a first author agent  118  uploads a picture to the social networking system  100 , the claim object  116  for the picture would include an assertion  120  that includes a target  126  for the picture uploaded to binaries  150 . The first author agent  118  may set the audience of the claim to be public, or set to Everyone, such that all agents on the social networking system  100  have been designated as audience agents  130  and the user-payload-copyright bit  134  is set to “OFF,” meaning that no rights to copy the content have been reserved and audience agents  130  may freely copy the claim  116  by the first author agent  118 . A second author agent  118  may subsequently copy the claim  116  by the first author agent  118  into a new claim object  116  where the new claim object  116  references the original claim object  116  as the target  126  of the assertion  120  of the new claim object  116 . The verb  124  of the assertion  120  of the new claim object  116  may be “HasPhotoSameAs,” a reserved verb in the social networking system  100  for claims that copy other claims. The user-payload-copyright bit  134  of the new claim object  116  that copied the original claim also references the user-payload copyright bit  134  of the original claim. If the original claim is deleted by the owner agent  128  of the claim, then the copyright control is either turned “OFF” or frozen in its last place. 
     Application-Copyright Bit 
     An application-copyright bit  136  controls if an audience agent  130  of the claim  116  can authorize an application to copy the claim on their behalf. For example, an application  146  may be authorized to share content on behalf of an agent, such as a photo-sharing application that shares photos from an event taken and uploaded by the agent using the application. In this example, the author agent  118  is the application and the owner agent  128  is the agent that authorized the application to generate the claims. The owner agent  128  may enable other agents listed in the audience to copy the claim into a new claim. An audience agent  130  may then authorize the application  146  to share the photos uploaded by the agent (also the owner agent  128 ) with a system external to the social networking system  100 , thereby copying the claim of the author agent  118 , where the author agent  118  is the application  146  authorized to generate claims on behalf of the owner agent  128 . In one embodiment, the authoring agent may enable members of the audience to copy the claim by authorizing an application to copy the claim on their behalf by setting the application-copyright bit to “OFF.” The social networking system  100  is not limited by the one or more copyright bits  132  defined by the owner agent  128  for synchronizing the content stored on the binaries, such as copying a claim, caching, device syncing, and the like to provide better an enhanced user experience. 
     Use-Right Bit 
     In one embodiment, a use-right bit  138  enables a claim to be “boosted” by the social networking system  100  in search results for the claim. For example, an agent that represents a restaurant may pay the social networking system  100  to boost positive recommendations made by other agents in the search results of a query made by a searching agent. The recommendations made by the other agents are claims in which the default setting of the use-right  138  bit is set to “ON” such that the agent representing the restaurant may boost those recommendations. An owner agent  128  of a claim  116  may disallow the claim from being boosted by turning off the use-right bit  138  through an interface with the social networking system  100 , such as a user interface and an application programming interface. In one embodiment, the boost request may be a function that operates on one or more claims. An agent may pay the social networking system  100  to boost a specific story or a query for claims, such as all claims that reference an object  148  for Coca-Cola, an agent on the social networking system  100 . 
     Metadata Objects 
     Metadata objects  140  may be included, or appended to, a claim object  116  by a social networking system  100  such that the metadata object  140  are private and only viewable and editable by the social networking system  100 . For example, a social networking system  100  may append a bit that tracks whether the claim object  116  was posted on an agent&#39;s timeline profile in the social networking system  100 . The “ON TL” bit is an example of a metadata object  140 . Other examples of metadata objects  140  include device information, publication surface, and other information generated by the social networking system  100  that is private and viewable only by the social networking system  100 . 
     Multiple Claims about a Subject in a Social Networking System 
     Having described the components of a claim object  116  in detail, the potential interactions between claim objects in a social networking system  100  is now described in further detail. In particular, the social networking system  100  may rely on the components of claim objects  116 , as described above, about multiple subjects in presenting information about a particular subject in the social networking system  100  to a viewing agent  142 . 
       FIG. 1C  illustrates a high level block diagram of a process of modeling interactions on a social networking system as a collection of claims, in one embodiment. As defined above, an author may make a claim, or a statement having a subjective truthfulness value or a truth coefficient, to an audience in a social networking system  100 . The claim comprises an assertion that includes a payload of a subject, a verb, and a target. A simple claim that may be made by an author in the social networking system  100  is where the author, a user in the social networking system  100 , currently lives. This may be inputted into the social networking system  100  as the user fills out his or her user profile. However, other agents in the social networking system  100 , which may include users and entities, may make other claims about where that user currently lives. These claims may be made to differing audiences that include different agents. By using claim objects that designate audiences, different claims may be made about the same subject that include different audiences such that the claim presented to a viewing agent depends on which one or more of the audiences that viewing agent is a member. 
     As illustrated in  FIG. 1C , three author nodes made claims that include assertions about a subject. A first author  152  may make a claim  160  about a subject  158 , such as a user (the first author  152 ) declaring in his profile that he currently lives in San Francisco, Calif. The first author  152  may make this claim  160  about the subject  158  of currently living in San Francisco, Calif. to an audience  176  that includes agent A  166 , agent B  168 , and agent C  170 . A second author  154  may make a different claim  162  about the subject  158  of where the user (the first author  152 ) currently lives, such as claiming that the user lives in Daly City, Calif., a suburb of San Francisco, Calif. A third author  156  may make another claim  164  about the subject  158  of where the user (the first author  152 ) currently lives, such as claiming that the user lives in Pacifica, Calif., another suburb of San Francisco, Calif. In another embodiment, a second author  154  may make a claim  162  that matches the claim  160  of the first author  152  that the user currently lives in San Francisco, Calif. In another embodiment, the third author  156  may make a claim  164  that matches the claim  162  made by the second author  154 , asserting that the user currently lives in Daly City, Calif. Each of the claims  160 ,  162 , and  164  may have different audiences  176 ,  178 , and  180  attached to the claims  160 ,  162 , and  164 . 
     As a result of three authors  152 ,  154 , and  156  making three different claims  160 ,  162 , and  164  of where a user (the first author  152 ) currently lives, a viewing agent  142  of the user profile of the first author  152  on the social networking system  100  may access one or more of the different claims  160 ,  162 , and  164  based on whether the viewing agent  142  is included in one or more of the audiences  176 ,  178 , and  180 . For example, if the viewing agent  142  is agent A  166 , included in the audience  176  for claim  160  made by the first author  152  that he currently lives in San Francisco, Calif., then the viewing agent  142  may be provided with that claim  160  that the user currently lives in San Francisco, Calif. However, because the viewing agent (agent A  166 ) is also included in the audiences  178  and  180  for the claims  162  and  164  made about the subject  158  of where the first author  152  currently lives, the social networking system  100  may also provide access to the claims  162 , and  164  made about the subject  158 . In this way, the viewing agent  142  may see that the first author  152  claim that he lives in San Francisco, Calif., the second author  154  claims that the first author  152  lives in Daly City, Calif., and the third author  156  claims that the first author  152  lives in Pacifica, Calif. Presented with this information, the viewing agent  142  is better informed about the actual city which the first author  152  lives in. In one embodiment, the social networking system  100  may enable the viewing agent  142  to select the city which he or she believes the first author  152  currently lives in, in effect creating a new claim by the viewing agent  142 . 
     Affinity scores, or calculated scores determined by the social networking system  100  that measure an affinity between objects, such as agents, may be used in ranking viewable claims about a subject. Suppose that agent A  166  is a close friend of the first author  152  and only weakly connected to the second author  154  and the third author  156 . In that case, agent A  166 , as the viewing agent  142 , may be provided with the claim  160  for the subject  158  based on the close connection to the first author  152 . Regardless of affinity scores, the social networking system  100  may heavily rank claims that have been authored by a viewing agent  142  in presenting claims to the viewing agent  142 . Suppose that the first author  152  has made the claim  160  about the subject  158  to everyone on the social networking system  100  and that agent A  166  is the third author  156 . In this case, the social networking system  100  provides the claim  164  to the viewing agent  142  (agent A  166 ) that the agent A  166  has made as the third author  156 , about the subject  158  that the first author  152  currently lives in Pacifica, Calif., even though the second author  154  has made a claim  162  that is different from the claim  164  made by the third author  156  because the social networking system  100  may heavily weight a claim made by an author in providing a claim to the author. 
     Other information received by the social networking system  100  may affect the ranking of multiple claims about a subject presented to a viewing agent  142 . In another example, the social networking system  100  may have received a different claim that the second author  154  is married to the first author  152 . The first author  152  may reciprocate the claim that he is married to the second author  154 . As a result, claims made by the second author  154  about the first author may be given more weight by the social networking system  100  in the ranking. In that case, the agent A  166 , as the viewing agent  142  and the third author  156 , may be provided with the claim  162  that the first author  152  currently lives in Daly City, Calif. authored by the second author  154  that is ranked higher than the claim  164  authored by the viewing agent  142  (agent A  166 ). In yet another embodiment, the social networking system  100  may provide a “best” claim made in relation to the subject  158  to the viewing agent  142  based on the ranking of claims made in relation to the subject  158  and based on the audiences  176 ,  178 , and  180  that the viewing agent  142  is a member. 
     The “payload” of a claim, or the claim&#39;s content, may only be viewed by an agent if the agent has been designated as an audience agent  130  of the claim. As a result, different agents in a social networking system  100  may view different “truths” based on their membership in the audiences of claims. For example, if agent B  168  and agent C  170 , both included in audience  176  of the claim  160  made by the first author  152 , are viewing the user profile of the first author  152 , they would be provided with San Francisco, Calif. as the current city in which the first author  152  lives. In contrast, agent D  172  viewing the same user profile of the first author  152  would be provided with Daly City, Calif. as the current city in which the first author  152  lives. Agent E  174 , who is not included in any audiences  176 ,  178 , or  180  of the claims  160 ,  162 , and  164 , may view the user profile of the first author  152  and be provided with a blank field for the current city where the first author  152  lives. In another embodiment, instead of the blank field, the social networking system  100  may generate a claim of where the first author  152  lives based on check-in events made publicly available by the first author  152 . In this way, the social networking system  100  provides one or more claims to a viewing agent  142  about a subject based on the audiences in which the viewing agent  142  is included as well as the social connections of the viewing agent  142  to authors of the claims made about the subject using the components of the claim objects  116  for the one or more claims. 
     This simple example of a user declaring where he currently lives on a user profile in the social networking system  100  illustrates that the social networking system  100  may use received information about agents in presenting claims to a viewing agent. The discussion above equally applies to more complex examples of claims made in a social networking system  100 , such as claims about interests, connections between agents, content posted by agents, check-in events, event attendance, restaurant recommendations, custom graph actions such as listening to music, playing a game, going to a concert, buying a new wardrobe, and the like. Due to the subjective nature of claims, the social networking system  100  may determine one or more truth coefficients for claims, further described in the following sections. 
     System Architecture 
       FIG. 2  is a high level block diagram illustrating a system environment suitable for evaluating claims in a social networking system, in accordance with an embodiment of the invention. The system environment comprises one or more user devices  202 , the social networking system  100 , a network  204 , and external websites  218 . In alternative configurations, different and/or additional modules can be included in the system. 
     The user devices  202  comprise one or more computing devices that can receive user input and can transmit and receive data via the network  204 . In one embodiment, the user device  202  is a conventional computer system executing, for example, a Microsoft Windows-compatible operating system (OS), Apple OS X, and/or a Linux distribution. In another embodiment, the user device  202  can be a device having computer functionality, such as a personal digital assistant (PDA), mobile telephone, smart-phone, etc. The user device  202  is configured to communicate via network  204 . The user device  202  can execute an application, for example, a browser application that allows a user of the user device  202  to interact with the social networking system  100 . In another embodiment, the user device  202  interacts with the social networking system  100  through an application programming interface (API) that runs on the native operating system of the user device  202 , such as iOS and ANDROID. 
     In one embodiment, the network  204  uses standard communications technologies and/or protocols. Thus, the network  204  can include links using technologies such as Ethernet, 802.11, worldwide interoperability for microwave access (WiMAX), 3G, 4G, CDMA, digital subscriber line (DSL), etc. Similarly, the networking protocols used on the network  204  can include multiprotocol label switching (MPLS), the transmission control protocol/Internet protocol (TCP/IP), the User Datagram Protocol (UDP), the hypertext transport protocol (HTTP), the simple mail transfer protocol (SMTP), and the file transfer protocol (FTP). The data exchanged over the network  204  can be represented using technologies and/or formats including the hypertext markup language (HTML) and the extensible markup language (XML). In addition, all or some of links can be encrypted using conventional encryption technologies such as secure sockets layer (SSL), transport layer security (TLS), and Internet Protocol security (IPsec). 
       FIG. 2  contains a block diagram of the social networking system  100 . The social networking system  100  includes a user profile store  206 , a web server  208 , an action logger  210 , a content store  212 , an edge store  214 , a claim generation module  216 , a claim store  220 , a claim presentation module  222 , a claim accuracy testing module  224 , and a claim evaluation module  226 . In other embodiments, the social networking system  100  may include additional, fewer, or different modules for various applications. Conventional components such as network interfaces, security functions, load balancers, failover servers, management and network operations consoles, and the like are not shown so as to not obscure the details of the system. 
     The web server  208  links the social networking system  100  via the network  204  to one or more user devices  202 ; the web server  208  serves web pages, as well as other web-related content, such as Java, Flash, XML, and so forth. The web server  208  may provide the functionality of receiving and routing messages between the social networking system  100  and the user devices  202 , for example, instant messages, queued messages (e.g., email), text and SMS (short message service) messages, or messages sent using any other suitable messaging technique. The user can send a request to the web server  208  to upload information, for example, images or videos that are stored in the content store  212 . Additionally, the web server  208  may provide API functionality to send data directly to native user device operating systems, such as iOS, ANDROID, webOS, and RIM. 
     The action logger  210  is capable of receiving communications from the web server  208  about user actions on and/or off the social networking system  100 . The action logger  210  populates an action log with information about user actions, in an effort to track them. Such actions may include, for example, adding a connection to another user, sending a message to another user, uploading an image, reading a message from another user, viewing content associated with another user, attending an event posted by another user, and loading a profile page of another user, among others. In addition, a number of actions described in connection with other objects are directed at particular users, so these actions are associated with those users as well. 
     As described and illustrated in  FIG. 1B  above, the social networking system  100  includes a warehouse layer  182  and a claim layer  184 . As illustrated in  FIG. 2 , a claim store  220  is a conceptualized database that stores claim objects  116 . The claim store  220  resides in the claim layer  184  of the social networking system  100  and points to storage and objects that are in the warehouse layer  182 . Claim objects  116  represent claims made by agents in the social networking system. Because claim objects  116  are fundamental to all objects on the social networking system  100 , a user profile store  206 , an edge store  214 , and a content store  212  may reside, conceptually, within the claim store  220 . For example, a user profile object for a user may be defined as a claim object  116  that includes the assertion that the social networking system  100  has generated an agent that corresponds to the user. Likewise, edge objects and content objects may be similarly defined as claim objects  116 . 
     User account information and other related information for a user are stored in the user profile store  206 . The user profile information stored in user profile store  206  describes the users of the social networking system  100 , including biographic, demographic, and other types of descriptive information, such as work experience, educational history, gender, hobbies or preferences, location, and the like. The user profile may also store other information provided by the user, for example, images or videos. In certain embodiments, images of users may be tagged with identification information of users of the social networking system  100  displayed in an image. The user profile store  206  also maintains references to the actions stored in an action log and performed on objects in the content store  212 . 
     The edge store  214  stores the information describing connections between users and other objects on the social networking system  100 . Some edges may be defined by users, allowing users to specify their relationships with other users. For example, users may generate edges with other users that parallel the users&#39; real-life relationships, such as friends, co-workers, partners, and so forth. Other edges are generated when users interact with objects in the social networking system  100 , such as expressing interest in a page on the social networking system, sharing a link with other users of the social networking system, and commenting on posts made by other users of the social networking system. The edge store  214  stores edge objects that include information about the edge, such as affinity scores for objects, interests, and other users. 
     The content store  212  stores content objects, such as photos, videos, status updates, and content items shared with users of the social networking system  100 . Content objects may comprise claim objects  116  that represent agent actions on the social networking system  100 . For example, a user may upload a photo from his mobile device to the social networking system  100 . Location information embedded in the photo saved in an exchangeable image file format (EXIF) may be used to validate the location of the user who claims to live in San Francisco, Calif. Other types of content objects, such as pages on the social networking system  100  that represent interests of users of the social networking system  100 , places, businesses and other real-world entities, as well as external websites  218 , are stored in the content store  212 . User interactions with content objects are stored in edge objects in the edge store  214 . 
     A claim generation module  216  generates claim objects  116  based on actions performed in a social networking system  100  as well as on external websites  218 . In one embodiment, certain user actions, such as declaring profile information attributes such as age, current living situation, relationship status, and the like, may trigger the claim generation module  216  to automatically generate claim objects  116  for the user-declared assertions. In another embodiment, the claim generation module  216  may provide a user interface for users to make claims about other objects in the social networking system  100 , such as claiming the best phone number of another user, claiming the physical addresses of a number of people, claiming that another user is a good co-worker, claiming that a restaurant has good chicken wings, and claiming appointments made through events inputted into the social networking system  100 . 
     A claim presentation module  222  provides to a viewing agent claim objects  116  that are accessible by the viewing agent based on whether the viewing agent is included in the audiences indicated in the claim objects  116 . In one embodiment, the claim presentation module  222  provides claim objects  116  associated with a subject, such as a user of the social networking system  100 , a page of the social networking system  100  representing an entity, and a concept or keyword that may be included in communications made by users of the social networking system  100  and extracted into an object on the social networking system  100 . The claim presentation module  222  may provide information included in a claim  116  about a subject user being a great pastry chef, for example, including a photo of a cake made by the subject user, to viewing agents included in the audience of the claim  116 . 
     As another example, an author may claim that the best dry fried chicken wings are served at Mission Chinese Restaurant to an audience by leaving a recommendation for a page representing Mission Chinese Restaurant in the social networking system  100 . A viewing agent of the page representing Mission Chinese Restaurant may be provided with the claim from the author if the viewing agent is included in the audience of the claim. Different recommendations, which may conflict, may be provided to a viewing agent based on claims made by authors in which the viewing agent is included in the audiences of the claims. Note that a different viewing agent, who is not included in the audience of the claim by the author that the best dry friend chicken wings are served at Mission Chinese Restaurant, cannot view that claim. The administrators of the page for Mission Chinese Restaurant may also not be able to view claims if they are not included in the audience of the claims. 
     A concept being discussed by users on a social networking system  100 , such as “Barack Obama” after the State of the Union address, may generate claim objects  116  in which authors discussing the speech may be claiming statements about Barack Obama, such as whether he is a good speaker, how the President addresses the issues, and so on. The claim presentation module  222  may provide these claims about the President, the State of the Union address, and/or politics to users included in the audience, in one embodiment. 
     A claim accuracy testing module  224  may provide a user interface to users of the social networking system  100  that prompts users to verify claims made in the social networking system  100 . In one embodiment, the claim accuracy testing module  224  may prompt a viewing agent for the accuracy of a claim based on a truth coefficient in the claim. The claim accuracy testing module  224  may provide a user interface for prompting the viewing agent for the accuracy of a claim. In that instance, the social networking system  100  may use user feedback or confirmation about the claim in determining the claim&#39;s truth coefficient, or truth coefficient, of the claim. The process of determining a truth coefficient is discussed in greater detail below. 
     As an example, the claim accuracy testing module  224  may provide a user interface to a viewing agent of the social networking system  100  that prompts the viewing agent whether a connected user graduated from Harvard. The response to the prompt may provide the social networking system  100  with more accurate information that may be trusted. In another example, the claim accuracy testing module  224  may prompt a viewing agent for the accuracy of a claim made about the viewing agent, where the claim designates an audience which the viewing agent is a member of, based on a determined truth coefficient of the claim. In another embodiment, the claim accuracy testing module  224  prompts a viewing agent for the accuracy of a claim only in a special circumstance defined by the social networking system  100  that does not violate the privacy settings of subject agents of the claim. The special circumstance may be defined based on a determined truth coefficient of the claim, retrieved information about the subject agent, retrieved information about the viewing agent, and any combination thereof. As a result, the claim accuracy testing module  224  enables viewing agents to provide more information to the social networking system  100  with regard to specific claims. 
     A claim evaluation module  226  retrieves information from various sources, such as user profile objects stored in a user profile store  206 , entries from an action log generated by an action logger  210 , edge objects stored in an edge store  214 , content objects stored in a content store  212 , external data gathered from external websites  218 , and user feedback claim data generated by a claim accuracy testing module  224 . Using the information retrieved from these sources, the claim evaluation module  226  may generate a truth coefficient in the claim being made by an agent of the social networking system  100 . In another embodiment, the claim evaluation module  226  may generate a truth coefficient for an author based on information retrieved from these sources and use the truth coefficient for the author as the truth coefficient for claims made by the author. Different models for evaluating claims may be used based on the type of the claim. Heuristics analysis and machine learning may, in one embodiment, be used in refining these models for evaluating claims. By evaluating claims and determining one or more truth coefficients for each claim, the social networking system  100  may use the truth coefficients in ranking claims when presenting them to viewing agents. 
     Evaluating Claims on a Social Networking System 
     Because multiple claims having different assertions about a particular subject may be made in a social networking system  100 , such as a best phone number for a particular agent, a social networking system  100  may determine a truth coefficient for claims using one or more methods. These methods of evaluating claims include determining a truth coefficient for an author agent based on information retrieved about the author agent, determining a truth coefficient for a claim made by an author agent to a particular audience, and determining false claims that may be falsely made by an author agent to an audience. A brief overview of each of these evaluation methods is presented, followed by example cases of evaluating a single claim, evaluating multiple claims, determining false claims, and determining a truth coefficient based on retrieved information from one or more sources. 
     Moreover, because any statement made on the social networking system  100  is a subjective assertion of a fact based on a particular viewpoint, there is no absolute truth of any statement made on the social networking system  100 . The social networking system  100  may approximate the truthfulness of a statement based on other claims, but any evaluation of “truth” or “likelihood” is made from a particular point of view, such as a viewing agent&#39;s point of view, or perspectives of other users connected to a subject user. As a result, a claim evaluation module  226  may have one or more models to determine the truthfulness of a claim. 
     In one embodiment, a truth coefficient may be determined for each agent making a claim about the subject. In another embodiment, a truth coefficient may be determined for each claim about the subject made by the agent of the social networking system  100 . Affinity scores may be determined by a social networking system  100  through one or more separate processes, described further in a related application, “Contextually Relevant Affinity Prediction in a Social Networking System,” U.S. patent application Ser. No. 12/978,265, filed on Dec. 23, 2010, hereby incorporated by reference. One or more factors used by the social networking system  100  in determining affinity scores may be used in generating models for determining truth coefficients. 
     Probabilistic models may be used to determine truth coefficients, in one embodiment. As a result, the truth coefficient of a claim may be a calculated probability that the claim is true. In another embodiment, the initial probability of a claim being true, or its truth coefficient, is set at some percentage, say, for example, 50%. Over time, the truth coefficient may change based on the information gathered about the claim. 
     In an embodiment, the social networking system  100  may determine a truth coefficient for a viewing agent  142  based on information gathered about the author agent  118  of the claim object  116  with respect to the viewing agent  142 . For example, a truth coefficient for an author agent  118  may be computed based on past interactions with the viewing agent  142 , such as a determined affinity score of the viewing agent  142  for the author agent  118 . A truth coefficient model for an author agent  118  may include several inputs, such as past social validation (a viewing agent&#39;s  142  past likes, comments, and shares of the author agent&#39;s  118  claim objects  116 ), an implied truth coefficient imported from friends of friends, factors used in determining affinity scores for objects in the social networking system  100 , manual inputs of truth coefficients by the author agent  118 , and negative inputs, such as overwritten claims by target agents in response to claims by the author agent  118 , a numeric representation of the number of agents that have a minimum threshold truth coefficient for the author agent  118 , and bad information included in claim objects  116  by the author agent  118  that has been validated by one or more other agents in the social networking system  100 . A negative truth coefficient may also be determined for a claim having an assertion based on negative feedback received from the viewing agent about the author of that claim, such as the viewing agent removing a tag by the author, the viewing agent choosing a conflicting claim over the claim by the author, and other agents of the social networking system providing negative feedback about the author when making claims to a particular audience. 
     In another embodiment, the claim evaluation module  226  may determine a truth coefficient for an assertion about a subject based on one or more claims by one or more authors making the assertion. A truth coefficient may be determined for each of the claims by the one or more authors making the assertion using the method described above of using an affinity of the viewing agent for the author in generating a truth coefficient for each claim. Then, the truth coefficients for the claims may be combined using a weighted function to determine a truth coefficient for the assertion for the viewing agent. In one embodiment, the viewing agent&#39;s affinities for the authors are used as weights. In another embodiment, the truth coefficients of the claims including the assertion made to the one or more audiences are inputted into a weighted function to determine the truthfulness of the assertion. The weighted function may also include other factors, such as truth coefficients for the authors, conflicting claims related to the assertion, and other claims related to the assertion. In a further embodiment, the truth coefficient for the assertion is computed by adding the truth coefficients received for the claims having the assertion. 
     Truth coefficients may be used by the social networking system  100  in various ways. For example, a viewing agent  142  may filter claims made in a user interface based on the determined truth coefficients for the viewing agent  142  for the claims. In another embodiment, claims may be ranked by determined truth coefficients. In a further embodiment, conflicting claims may be ranked using truth coefficients such that only a “best” claim, the claim with the highest truth coefficient, is displayed to the viewing agent  142 . Complex queries may be run against claims that include, as a search term, the truth coefficient for a particular set of viewing agents  142 , in an embodiment. In further embodiments, an assertion  120  may be highlighted by the social networking system  100  based on the truth coefficient determined for the assertion  120 . Highlighted assertions  120  in this manner may be exported to a third party application in which advertisers may make payments to the social networking system  100  for access to the highly truthful information, conditioned on the privacy model of the social networking system  100 . In this way, a new social graph may be modeled on claims that account for the gradients of truthfulness for assertions made on the social networking system. 
     Truth Coefficients Determined for Agents 
     The methods of determining truth coefficients may be categorized as either determining a truth coefficient for an author or determining a truth coefficient for each claim, in one embodiment. Reputation scores for truthfulness, or agents&#39; truth coefficients based on the viewing agent&#39;s perspective of the agent, may be determined by the claim evaluation module  226  based on the agents&#39; past history of making claims. A truth coefficient may be determined for any combination of components of a claim object. For example, a model may be used to determine a truth coefficient for an author making claims to a particular audience about a particular subject. As a result, all claims made to that particular audience by the agent about that particular subject may be assigned the truth coefficient determined by the social networking system  100 . Separately, a different model may be used to determine a truth coefficient for an author making claims to any audience about a particular subject. In that case, all claims made about the particular subject may be assigned the determined truth coefficient using the different model. 
     A social networking system  100  may generate a truth coefficient for an author separate from a different truth coefficient for a particular claim made by the author. Truth coefficients may be used to determine an overall truth coefficient for an author. Thus, in one embodiment, a truth coefficient may be determined for an agent based on the truth coefficients for all claims made by the agent. The truth coefficient determined for that agent may then be used by the social networking system  100  in ranking claims presented to a viewing agent. 
     In a further embodiment, a truth coefficient may be determined for an agent based on other claims related to the claims made by the agent as well as other information received by the social networking system about the agent. For example, as illustrated in  FIG. 2 , the claim accuracy testing module  224  may prompt an agent for feedback about claims about that agent. This enables agents to provide more assertions, or more claims, about a particular claim. Using that information, the truth coefficient for an agent may be affected by the feedback received. For example, if an agent confirms a claim when prompted by the claim accuracy testing module  224 , the reputation of the author of the claim, or the truth coefficient for the author, may increase. However, if an agent denies a claim or chooses another claim, the reputation of the author of the claim may be diminished, meaning the truth coefficient for the author may decrease. 
     Agents may carry a reputation that is determined by the claim evaluation module  226 . In another embodiment, a reputation score for an agent may be determined by a separate process in the social networking system  100  and operate asynchronously from the claim evaluation module  226 . In that embodiment, the claim evaluation module  226  may retrieve the stored reputation score for the agent making the claim being evaluated. The claim evaluation module  226  determines a reputation score measuring the truthfulness of claims made by a particular agent with respect to a viewing agent&#39;s perspective on the social networking system  100 . 
     An initial value may be assigned for an agent&#39;s reputation score. The initial value may be adjusted up or down based on user feedback received from users affirming or disaffirming the agent&#39;s reputation for truthfulness. A reputation score for an agent may also be based on a viewing agent&#39;s social connections using a reputation model that averages evaluated claims authored by the agent. The reputation score may then be used as a truth coefficient for the agent. As a result, the social networking system may rank claims by the agent based on the truth coefficient for the agent. 
     For example, a first user may make the claim that he is married to a second user on the social networking system  100 . In one embodiment, a first viewing agent may make a conflicting claim that the first user is not married to the second user, such that the claim made by the first user would not be provided to the first viewing agent. A second viewing agent, unaware of the first user&#39;s tendency to make false claims on the social networking system  100 , may be provided with the first user&#39;s claim that he is married to the second user based on the second viewing agent&#39;s social connections on the social networking system  100 . In effect, the agent reputation score for a user may be determined as an average of the truth coefficients for claims made by the user taking into account a viewing agent&#39;s social information, such as affinity scores for authors of the claims, in one embodiment. A user&#39;s reputation for truthfulness may then be stored as an agent reputation score in a viewing agent&#39;s user profile object for the user, in one embodiment. 
     Factors used to determine affinity scores may be used to determine a reputation score for an agent, such as determining whether an agent is generating spam or malware on the social networking system  100 . Such factors include monitoring interactions between agents on the social networking system  100  within a predefined time period, such as the last 12 hours, the last 24 hours, the last week, month, two months, three months, and so on. Interactions between agents include comments, “likes” (expressions of approval and/or interest), posts on a “wall” associated with an agent, interactions on a same thread, agents tagged in the same photo, a second agent linking to a comment by a first agent, sharing content, mentioning an agent in a wall comment, viewing a user profile or entity&#39;s page on the social networking system  100 , messages exchanged between agents, chats between agents, video chats, a “poke” (an indication that an agent requests the attention of another agent on the social networking system  100 ), initiating a two-way connection to another agent on the social networking system  100  such as “friending” a user or becoming a “fan” of a page, severing a relationship with a connected agent, being “checked-in” at the same location as another agent, attending the same event as another agent, viewing an album uploaded by another agent, posting content in a group in which another agent is a member, sharing membership in a group with another agent, subscribing to another agent to enable a one-way connection with that agent on the social networking system  100 , and declaring attendance to a same school, local city, workplace, family member, or stated relationship with another agent. One factor for determining affinity scores, as well as whether an agent is a malicious actor, includes measuring the amount of time between interactions between agents and the social networking system  100 . Factors for determining malicious agents may include excessive posts by an agent, excessive initiations of two-way connections by an agent, and analyzing information declared by agents for matches with known malicious actors. These factors may be used by the claim evaluation module  226  in determining reputation scores for agents. 
     Heuristics analysis may also be used to keep track of the assertions made by users and discount assertions made by users that have a low reputation score based on previous assertions made by those users. Based on prior fraudulent assertions, a user&#39;s reputation score may be decreased. In one embodiment, a user&#39;s reputation score will cause a truth coefficient for a claim being generated by the user to be automatically discounted if the user&#39;s reputation score did not meet a predetermined threshold reputation score. 
     In one embodiment, an agent may manually determine its own reputation score through an interface with the social networking system  100 , such as a user interface, an application programming interface (API), or other communication method with the social networking system  100 . In another embodiment, an author may assign a reputation for truth score for the author based on different times of the day or during a particular time period. Between the hours of 8 pm and midnight, an authoring user may assign himself a truth coefficient of 0.8, for example. In further embodiment, the social networking system  100  may assign a truth truth coefficient for all claims by an author to be a score of 1, meaning that the social networking system  100  may assume that all claims made by an author are believed to be true by the author. 
     Truth Coefficients Determined for Claims 
     Truth coefficients may be determined for claims using models that include one or more factors. A claim evaluation module  226  generates a model to score confidence in claims made on the social networking system  100 . In one embodiment, a model uses weights for factors in the model, and, over time, the weights may be adjusted using machine learning methods. Regression analysis, in one embodiment, may be used in the model to include or exclude factors that are determined to be relevant or not relevant to evaluating claims in the social networking system for a particular viewing agent, based on machine learning and heuristics analysis of the associated claim objects. In one embodiment, a different scoring model may be generated to score confidence in claims made by a particular author to a particular audience about a particular assertion. In that scoring model, truth coefficients for all claims made about the particular assertion may be combined using a truth function to determine the truth coefficient in the claim made by the particular author. Different types of truth functions may be determined for different types of assertions made to different audiences, having different subjects, and based on any attribute that may be used to distinguish content, users, entities, and agents in the social networking system  100 . Truth coefficient models may be weighted differently based on received information by the social networking system  100  regarding claim types. As a result, a correction of a business address for an entity may have different weights than agents tagging a photo with other agents. 
     In other embodiments, other types of information may be used in determining models for claims, including social validation, trust coefficients of indirect connections, factors used in determining affinity scores, manual adjustments by agents, factors used in determining whether an agent is generating spam or malware on the social networking system  100 , negative feedback received about claims, trusted connections having negative truth coefficients for an author or a claim, the total number of agents that trust a claim or an author, overwritten claims, and bad information listed in an assertion of a claim. For example, social validation, or interactions by other agents connected to the author on the social networking system  100 , such as commenting on a content item, sharing a content item or node, “liking” a content item or node by clicking on a link to express approval, mentioning an agent or node in a content item, or tagging an agent or node in a content item, may be used as an input in determining a claim&#39;s truth coefficient because social validation adds legitimacy to a claim. Trust coefficients of indirect connections to a viewing agent, such as a trust coefficient for an entity liked by a trusted friend of the viewing agent, may also be used in determining a trust coefficient, or claim truth coefficient, for a claim authored by the entity using the trust coefficient for the entity from the perspective of the trusted friend of the viewing agent. This implied trust coefficient may be useful because of the trust relationship between the friend and the viewing agent, which may be a trust coefficient having a minimum trust coefficient. The total number of agents that trust a claim or an author may also have significance in determining a trust coefficient for a claim or a trust coefficient for an author. 
     Other factors that may be used in determining models for claims include negative feedback received about claims, identifying trusted connections having negative truth coefficients for an author or a claim, claims by a first agent overwritten by a second agent, and bad information listed in an assertion of a claim. For example, negative feedback may include an agent clicking on a link to “X” out the claim, providing feedback that the claim is unwanted, uninteresting, sexually explicit, against the agent&#39;s views, offensive, misleading, untrue, repetitive, or feedback manually inputted by the agent. In another embodiment, the social networking system  100  may have generated negative trust coefficients for authors and claims for trusted connections of a viewing agent. Trusted connections of a viewing agent may have trust coefficients higher than a predetermined threshold. As a result, the negative trust coefficients for authors and claims generated for trusted connections of a viewing agent may be used in determining trust coefficients for the viewing agent. 
     In a further embodiment, the fact that a claim has been overwritten, meaning that a new claim with a new assertion has replaced the overwritten claim, may also be used in determining a model for claims. In yet another embodiment, an agent may report to the social networking system  100  that a claim includes bad information by attempting to use the information included in the claim. For example, a viewing agent may view a claim that an agent&#39;s phone number is 867-5309 and attempt to establish a phone call to that phone number. In calling the phone number, the viewing agent may be informed that the phone number is a bad number, or that the phone number does not exist. As a result, the social networking system  100  may use that information to determine the claim truth coefficient of the claim that includes the bad information. 
     In one embodiment, a social networking system  100  uses a machine learning algorithm to analyze user feedback to retrain one or more models for determining truth coefficients. Other uses of machine learning include selecting inputs in models to determine truth coefficients of claims, determining predetermined thresholds for prompting a viewing agent for feedback regarding a claim, and generating truth coefficients for an assertion based on derivative claims and user feedback regarding claims that include the assertion. 
     Conflicting Claims 
     Because of the subjective nature of claims, claims about a particular subject may be conflicting. The existence of conflicting claims may indicate that one of the claims may be false or that there are multiple claims that may all be truthful for a particular subject. Returning to  FIG. 1C , in which multiple authors have generated multiple, conflicting claims about a particular subject, the social networking system may also evaluate the truthfulness of the claims. As a result of the viewing agent (agent A  166 ) being included in the audiences  176 ,  178 , and  180  for the claims  160 ,  162 , and  164  made about the subject  158  of where the first author  152  currently lives, the social networking system  100  may evaluate the truthfulness of all the claims  160 ,  162 , and  164  made about the subject  158  in light of the connections of the viewing agent (agent A  166 ). A different truth coefficient may be determined by the claim evaluation module  226  for each of the claims  160 ,  162 , and  164 . Using the determined truth coefficients, the social networking system  100  may then provide the most appropriate claim for the subject  158  to the viewing agent (agent A  166 ). In one embodiment, the claims  160 ,  162 , and  164  are presented to the viewing agent in order of truth coefficient, from highest to lowest. In another embodiment, the claim with the highest truth coefficient is presented to the viewing agent. 
     In this example, the assertion of the claim of where the first author  152  current lives is correct or incorrect, true or false. The social networking system  100 , recognizing the inconsistency, may prompt the third author  156  (agent A  166 ) to ask where the first author  152  currently lives, either Pacifica (from claim  164 ), Daly City (from claim  162 ), or San Francisco (from claim  160 ). The first author  152  may respond that he lives in Daly City, indicating that the second author  154  correctly claimed where the first author  152  currently lives. Alternatively, agent A  166  (the third author  156 ) may recognize that the second author  154  may be more correct because of a recent move and, as a result, copy the claim  162  to the claim  164  about the subject  158  of where the first author  152  currently lives. In another embodiment, the social networking system  100  may recommend to the third author  156  (agent A  166 ) to adopt the claim  162  made by the second author  154  based on the reciprocated claim that the relationship status between the second author  154  and the first author  152  is married. 
     In one embodiment, a social networking system  100  may measure, as a factor of determining an agent&#39;s reputation score, how often the agent generates false claims. False claims may be determined by prompting an agent to verify a claim made about the agent, evaluating claims made by agents about a subject in aggregate to determine which agents generated a conflicting claim that may be judged to be untrue when compared to the majority of claims, and machine learning techniques used to determine agents making false claims based on other agents known to make true claims. False claims may have negative truth coefficients, in one embodiment. 
     As an example, a first user that tags a second user in a photo on the social networking system  100  is claiming that the second user appears in the photo. In reality, the second user may not appear in the photo and the first user may be intentionally making a false claim to make a joke about the second user. For example, a first user may claim, as a joke, that a second user appears in a photograph of Jabba the Hut from Star Wars, tagging the second user in the picture on the social networking system  100 . The second user may be fine with the joke and may confirm the tagging by the first user. In this example, the first user and the second user have both made claims that the second user appears in the picture of Jabba the Hut. However, other viewing agents may respond to a prompt from the social networking system  100  that the tag of the second user is a false claim. 
     Other mechanisms, such as image recognition techniques, may be used to identify faces in photos, thereby recognizing the photo of Jabba the Hut is not a picture of the second user. As a result, the claim evaluation module  226  may adapt the model determining truth coefficients for photo tags by the first and second users to take into account that the first and second users tend to corroborate each other&#39;s false claims. Using the user feedback, machine learning methods may be used to identify patterns of users&#39; false claims on the social networking system  100 . Based on an analysis of hundreds of thousands of photos, the claim evaluation module  226  may determine that some agents are more prone to make false claims about tagging photos of other agents. The claim evaluation module  226  may identify these users that have a tendency to make false claims on the social networking system  100  for certain types of claims. 
     Negative truth coefficients may be assigned to claims that are not chosen or selected among conflicting claims presented to a viewing agent. For example, a second claim made by a second authoring agent about a subject agent that conflicts with a first claim made by a first authoring agent may be chosen by the subject agent to be presented to an audience, such as all agents of the social networking system  100 . Because the second claim was chosen by the subject agent to be presented to an audience, it may be assumed that the second claim is more truthful than the first claim, in one embodiment. As a result, the model used in determining a truth coefficient for the first claim and the second claim may take into account that the second claim conflicting with the first claim was selected by the subject agent. The first claim may be assigned a negative truth coefficient, in one embodiment. To give this example a context within the social networking system  100 , the first claim may be that the subject agent, a business entity having a place of business at an address in the real-world, is located at 123 Main Street. The second claim may be that the subject agent is located at 456 Market Street, San Francisco, Calif. If the second claim was chosen over the first claim by the subject agent, then the truth coefficient for the first claim would be lower than the truth coefficient for second claim, in one embodiment. In another embodiment, if a third-party application, such as a business listings application, verifies that the subject agent is located at 456 Market Street, San Francisco, Calif., then the truth coefficient for the first claim may be set to 0. A negative truth coefficient may be assigned, in another embodiment, based on whether the claim has been purposefully made to be incorrect. 
     Heuristics analysis, or gathering and analyzing different types of information, may be used to identify false claims. For example, check-in events may be falsely created by some users of the social networking system  100 , such as checking in other users at a location when those users are actually not physically present in that location. An author may check himself and two other users in at the Golden Gate Bridge in San Francisco, Calif., even if the two other users are not actually present at the Golden Gate Bridge. The other two users may have just recently checked-in over 2000 miles away in New York City at the Statue of Liberty. The claim evaluation module  226  may analyze this information based on the GPS location technology of the users claiming they are in New York City, and determine that the author of the check-in event at the Golden Gate Bridge has made a false claim about the other two users being present with him using heuristics analysis techniques. 
     Evaluating a Single Claim on a Social Networking System 
     Having described various methods of determining truth coefficients for claims and authors in a social networking system  100 , the following figures illustrate various embodiments of evaluating claims using one or more of the methods described above.  FIG. 3  illustrates a flow chart diagram depicting a process of evaluating a claim in a social networking system. Throughout the description of these figures, example use cases are also described to further illustrate how claims may be evaluated in the social networking system  100  by determining truth coefficients from the vantage point of viewing agents. 
     As illustrated in  FIG. 3 , an assertion of a claim about a subject agent is received  302  by the social networking system  100 . This assertion may be made by an authoring user of the social networking system  100 , in one embodiment. In another embodiment, the assertion may be made by an authoring application or page representing an entity on the social networking system  100 . In yet another embodiment, the assertion may be made by an external system or external website communicating with the social networking system  100 . The assertion of the claim may comprise an action performed by a user on the social networking system  100 , such as a user checking into a place using a mobile device that has GPS location awareness functionality, a user tagging another user in a photo that has been uploaded to the social networking system  100 , a user calendaring an event on the social networking system  100  and inviting other users to the event, a user declaring biographical information on a user profile about himself or herself, a user listing contact information for another user on the social networking system, a user confirming a tag of another user in a photo or video on the social networking system, an application communicating to the social networking system  100  that a user ordered an item on a menu using the application using a custom graph action and a custom graph object, and the like. 
     After an assertion of a claim about a subject agent is received  302 , information associated with the claim about the subject agent is retrieved  304 . This information may include other information about the subject agent that may help corroborate the claim being made, such as location information from other check-in events made by the subject agent, information retrieved from user profiles of other users connected to the subject agent, activity recorded in an action log on the social networking system  100 , information related to the claim retrieved from edge objects associated with the subject agent, information retrieved from external websites related to the claim, and other information received from third-party providers related to the claim. For example, a user may claim that another user is with him at the Eiffel Tower in Paris, France in a check-in event on the social networking system  100 . The audience of this claim may be selected users that are connected to the user, all users connected to the user, or the claim may be made publicly available and searchable. In truth, the other user, the subject user of the claim, may actually be located in New York City, having just checked-in at the Statue of Liberty. That check-in event in New York City may have a different audience, such as users connected to the subject user. Information about the subject user, including his recent check-in at the Statue of Liberty and the audiences selected for the check-ins, may be retrieved  304  after the claim that the subject user is located at the Eiffel Tower is received  302 . 
     After the information associated with the claim about the subject agent is retrieved  304 , a truth coefficient is determined  306  for the claim based on a probabilistic model and the retrieved information associated with the claim. An administrator may, in one embodiment, manually determine factors in a claim model, such as determining weights for different factors using the claim evaluation module  194 . The claim evaluation module  194  may select factors in a claim model, in another embodiment, based on the results of regression analysis and user feedback regarding prior claim objects. Returning to the example above, the conflict between the two check-in events for the same user, the first being at the Eiffel Tower in Paris and the second being at the Statue of Liberty, may be assigned weights in the claim model that evaluates the claim based on the perspective of a viewing agent in the audience selected for the claim. The claim truth coefficient for a viewing agent that has a proclivity to believe claims made by the author for the claim that the subject user is at the Eiffel Tower may be higher than the claim truth coefficient for another viewing agent that does not have the same proclivity. In this way, the social networking system  100  may determine  306  different truth coefficients based on the viewing agents&#39; affinities for other users, as well as proclivities to believe the asserting user&#39;s claims. 
     After a truth coefficient has been determined  306  for the claim with respect to a viewing agent, the claim and associated truth coefficient are stored  308  in the social networking system associated with the viewing agent. The claim and associated truth coefficient may be stored  508  in the social networking system  100  as a claim object  116  in the claim store  220 . In one embodiment, a claim object  116  is automatically generated when a claim is received  302  by the social networking system  100 . The determined truth coefficient for the claim is stored in the previously generated claim object  116  associated with the claim. For example, a user filling out his or her own user profile may declare biographical information, including the user&#39;s age, gender, current city, hometown, colleges or universities attended, employment history, and the like. As the user fills out the user profile object, an assertion of a claim about the user is received  302 . A claim object  116  may be automatically generated for the claim and pre-populated with an initial claim truth coefficient. Once information about the claim is retrieved  304 , a truth coefficient may be determined  306  for the claim object  116 . In another embodiment, a truth coefficient may be determined  306  for the claim object  116  based on a viewing agent requesting the claim. In that embodiment, the truth coefficient is based on the viewing agent&#39;s affinity scores for the agent and other objects in the social networking system  100 , such as the viewing agent&#39;s proclivities for the authoring agent&#39;s reputation for truthfulness. If the viewing agent is inclined to accept false claims made by the authoring agent, then the proclivity of the viewing agent may be taken into account while determining the truth coefficient of the claim for the viewing agent. A claim object  116  for the claim made in the social networking system  100  may include a plurality of truth coefficients associated with a plurality of viewing agents. As a result, the social networking system  100  may account for a viewing agent&#39;s social relationships with other users on the social networking system  100  when determining the claim truth coefficients of claims made on the social networking system  100 . 
     Custom graph actions and custom graph objects may also be evaluated by the social networking system  100  as claim objects. For example, a page representing Mission Chinese Restaurant may make a claim that a user of the social networking system  100  ordered Szechuan Chicken, using a custom graph action of “order” and a custom graph object of “Szechuan Chicken.” The page, an entity on the social networking system  100 , may have a sophisticated ordering system that enables a credit card transaction associated with the user to be communicated to the social networking system  100 , for example. The page for Mission Chinese Restaurant may be connected to an external website  218  that enables users of the social networking system  100  to be connected to the external website  218  to facilitate communication of what the users ordered through the external website  218 . The claim made by the page may be evaluated by the claim evaluation module  226  to have a high truth coefficient because of the technology underlying the information included in the claim. 
     Evaluating Multiple Claims on a Social Networking System 
       FIG. 4  illustrates an interaction diagram of a process for evaluating claims to provide information based on the evaluated claims to a viewing agent of the social networking system  100 .  FIG. 5  illustrates a high level block diagram depicting sources for information used in evaluating claims in a social networking system. As illustrated in  FIG. 4 , several authors may make different claims about a subject to different audiences. The social networking system  100  receiving these claims may provide a statement about the subject involved in the claims based on the received claims and using information retrieved about the viewing agent. The statement may be a “best” claim for the viewing agent  142 , in one embodiment. The statement may also include all claims that have assertions that include the subject that are viewable by the viewing agent  142 , in another embodiment. The claims may be ranked by truth coefficient, in a further embodiment. In this way, evaluated claims may be provided to users of a social networking system  100 . 
     A first claim about a subject is received  402  by the social networking system  100  from a first author  152 . This claim may be received  402  by the social networking system  100  through various user interfaces with the first author  152 , such as a user selecting a birth date on his or her own profile, a user entering information to be declared on his or her profile, a user making a claim that another user is a good cook through a claim generating user interface provided by a claim generation module  216 , and so on. Similarly, a second claim about a subject is received  404  by the social networking system  100  from a second author  154  and a third claim about a subject is received  406  by the social networking system  100  from a third author  156 . 
     A request about the subject may be received  408  from a viewing agent  142  by the social networking system  100 . The request about the subject may be received  408  from the viewing agent  142  through a request for a web page including the subject, such as a user&#39;s profile information, a page showing all claims made about a user including the subject, and an application that provides all claims made about the subject. In one embodiment, the viewing agent  142  may be unconnected to a user and request contact information about the user. In that embodiment, the request for contact information is a request received  408  by the social networking system  100  about the contact information, the subject of one or more claims made by users of the social networking system  100 . 
     The social networking system  100  may retrieve  410  information about the viewing agent in response to receiving  408  the request about the subject. The information retrieved  410  by the social networking system  100  may include social information about the viewing agent  142  on the social networking system  100 , such as connections to other users, entities, and concepts on the social networking system  100  retrieved from user profile objects, an action log, edge objects, and content objects in the social networking system  100 . Other information that may be retrieved  410  includes truthfulness reputation scores and affinity scores for users and entities making claims about the subject that are connected to the viewing agent  142  and secondary connections of the viewing agent  142 . 
     Based on the retrieved information about the viewing agent and the first, second, and third claims received about the subject, a statement may be generated  412  about the subject by the social networking system  100 . The statement may comprise a recitation of the first, second, and third claims, in one embodiment, provided that the viewing agent  142  is included within the audiences for the first, second, and third claims. In another embodiment, the statement may include a “best” claim from among the first, second, and third claims based on the retrieved information about the viewing agent. For example, a viewing agent may be provided with the best phone number for a particular user of the social networking system  100  from among three claims with different phone numbers by different authors. Information about the viewing agent  142 , such as whether the viewing agent is connected to authors, reputation scores of those authors, and affinity scores for the authors, may be used in selecting the best phone number for the particular user, taking into account social information about the viewing agent  142 . The best phone number for the particular user may then be generated  412  in a statement in the social networking system  100 . 
     In one embodiment, the generated  412  statement may be stored in the social networking system  100 . In a further embodiment, the best claim from among the first, second, and third claims may be determined by combining truth coefficient values for the first, second, and third claims. For example, if the first and second claim about a phone number for the particular user have truth coefficient values of 0.5 and 0.6 and recite the same phone number, 867-5309, then the social networking system  100  may combine these truth coefficient values to provide a truth coefficient value for the assertion that the particular user&#39;s phone number is 867-5309. If the third claim about the phone number for the particular user has a truth coefficient value of −0.5 and the assertion of the phone number for the third claim is the same, 867-5309, then the total truth coefficient value for the assertion that the phone number of the particular user is 867-5309 is 0.6. If the third claim has a different assertion of the phone number, such as 123-4567, then the truth coefficient value for the third claim would not be added to the truth coefficient values of the first and second claims. In that case, the assertion that the particular user&#39;s phone number is 867-5309 may be associated with a truth coefficient of 1.1 (adding the truth coefficient of the first and second claims), while the assertion that the particular user&#39;s phone number is 123-4567 may be associated with a truth coefficient of −0.5 (the truth coefficient of the third claim). In generating 412 a statement about the subject, the truth coefficients for the assertions, based on the claims about the subject, may be compared. In this case, the generated  312  statement may include the “best” claim based on the combined truth coefficient, that the particular user&#39;s phone number is 867-5309. This statement would then be provided 414 for display in a user interface or other application on the social networking system  100  to the viewing agent  142  responsive to the request. 
     Using Different Sources of Information in Evaluating Claims in a Social Networking System 
     In evaluating claims, a social networking system  100  is not limited to a viewing agent&#39;s social information, such as affinity scores, and truth coefficients for authors and claims to determine truth coefficients for claim. A social networking system  100  may access multiple sources of information, including related claims generated by agents that may or may not be connected to the viewing agent. Additionally, heuristics analysis may be used in analyzing the different types of claims and models for determining truth coefficients. 
     A claim evaluation module  226  interfaces with various modules on a social networking system  100  as well as external websites  218  to process information about claim objects  116  of the social networking system  100 . Using identifying information about the author agent of a claim, user profile objects, entries in an action log, edge objects, and content objects may be retrieved by the claim evaluation module  226  to extract information related to an assertion made in a claim object  116 . A claim evaluation module  226  may also retrieve external data  190  that may include content on a third-party website and other data licensed from third-party providers. In one embodiment, the information retrieved from external websites  218  may be processed in an asynchronous batch process separate from the claim evaluation module  226 . 
     As illustrated in  FIG. 5 , the social networking system  100  includes various sources of information that may be used in generating claim objects and evaluating assertions in the generated claim objects made on the social networking system  100  in one embodiment, including user profile objects  502  that represent users of the social networking system  100 , an action log  504  that records actions performed on the social networking system  100 , edge objects  506  that represent edges interconnecting nodes of the social networking system  100 , content objects  508  that represent content added to the social networking system  100  by users and entities, external data  510  that may be retrieved on websites and systems external to the social networking system  100 , and user feedback claim data  512  that may be gathered by a social networking system  100  requesting user feedback about claims. 
     User profile objects  502  include declarative information about the user that was explicitly shared by the user and expressed in an action on objects in the social networking system  100 . In one embodiment, a user profile object  502  may include thirty or more different data fields, each data field describing an attribute of the corresponding user of the social networking system  100 . A claim object  116  may be generated for every piece of declarative information included in a user profile object  502 , such as a user&#39;s age, gender, hometown, location, educational history, employment history, and interests. A claim evaluation module  226  may generate a claim object  116  for a particular claim, such as a user claiming to have graduated from Harvard by declaring the assertion on the user&#39;s profile. However, an agent representing Harvard may make a conflicting claim that the user did not graduate with a degree from Harvard, but instead completed a summer seminar course at Harvard. As a result, the claim evaluation module  226  is provided with an additional source of information in evaluating the truthfulness of the particular claim. 
     An action log  504  and edge objects  506  are two additional sources of information that may be relied upon by the claim evaluation module  226  in gathering information related to a claim for determining a truth coefficient for the claim. An action log  504  records user interactions with various objects on the social networking system  100  as well as custom graph actions performed on graph objects on external systems. Edge objects  506  may represent interactions that occur between objects on the social networking system  100 , such as messaging between users, a user&#39;s expression of interest in a content item posted by another user or an entity on the social networking system such as a page, a user commenting on a content item posted by another user, and the like. User interactions may be used by a claim evaluation module  226  in determining a claim truth coefficient for a claim made by a user, in one embodiment. For example, if a user claims to have graduated from Harvard as declared through the user&#39;s profile, user interactions such as having connections on the social networking system to other users who also claim that the user graduated from Harvard may be used by the claim evaluation module  226  in determining a truth coefficient for that claim. Other user activity and interactions may be gathered and analyzed by the claim evaluation module  226 , such as membership in groups including the keyword “Harvard,” attendance at events including the keywords “Harvard,” and “Ivy League,” and interactions with pages on the social networking system relating to Harvard. 
     Content objects  508 , such as status messages, messages between users, page posts, photos, videos, notes, events, check-in events, and the like, may be used in evaluating assertions made in claims by users of the social networking system  100 . External data  510  gathered from websites external to the social networking system  100 , such as an external system for tracking alumni of colleges, may be used by a claim evaluation module  226  in determining a truth coefficient for the claim. For example, attendance at an event for Harvard alumni by the user claiming to have graduated from Harvard may be retrieved from a content object  508  for the event or from external data  510  gathered from the external system for tracking alumni of Harvard. This type of information may positively influence a truth coefficient for the claim as determined by the claim evaluation module  226 . 
     User feedback claim data  512  may be gathered by a social networking system  100  in order to validate one or more claims made by a user of the social networking system  100 . For example, the social networking system  100  may provide a user interface that enables users to respond to questions posed by the social networking system  100 , such as whether the viewing agent was a classmate with a user at Harvard, whether the viewing agent was roommates with the user while at Harvard, and whether the user graduated from Harvard. This user feedback claim data  512  may be used by the claim evaluation module  226  to influence a truth coefficient of the claim. 
     Claim objects  116  may be generated by the social networking system  100  through existing user interfaces, such as a text input interface used to tag a user in a photo, video, check-in event, or another content object  508  on the social networking system  100 , another user interface used to declare profile information about users, as well as other user interfaces that may be used by users to generate claims about other users. In one embodiment, claim objects  116  may be generated from existing user profile objects  502 , edge objects  506 , content objects  508 , and external data  510  such as custom graph actions and custom graph objects. 
     A claim evaluation module  226  may retrieve information from various sources on the social networking system  100  to evaluate claims having assertions made about a subject based on social information of the viewing agent  142  of the claims. The claim evaluation module  226  may use one or more methods of computing a truth coefficient  514 . In one embodiment, a truth coefficient  514  may be determined for an author of a claim about the subject for a particular viewing agent  142  of the social networking system  100  based on a history of past interactions between the viewing agent  142  and the author of the claim. Selected claim objects  516  may be provided by the claim evaluation module  226  to a viewing agent  142  based on the accessibility of the claim objects  116  with respect to viewing agent  142 , in one embodiment. In another embodiment, selected claim objects  516  may be provided by the claim evaluation module  226  to a viewing agent  142  in a ranking based on the determined truth coefficients  514  of the selected claim objects  516 . 
     As an example, the claim evaluation module  226  may retrieve all claim objects  116  associated with the subject of a user&#39;s age to determine truth coefficients  514  for the claim objects  116 . The user may claim that she is 29 while her friends may make claims that the user  30 . Other information about the user may be retrieved from various sources on the social networking system  100  to help determine the truth coefficients  514 , such as actions performed by users on the social networking system  100 . Using a prediction model having several factors, the claim evaluation module  226  may determine truth coefficients  514  for the claim objects  116  associated with the subject of her age, assigning one truth coefficient  514  to her claim that she is 29 and a different truth coefficient  514  to her friends&#39; claim that she is 30 years old based on a viewing agent&#39;s affinity scores for the user and the user&#39;s friends. 
     Truth coefficients  514  may be stored as metadata in claim objects  116  for each viewing agent  142 . The affinity score of the viewing agent  142  for the user may affect the truth coefficients  514  determined by the claim evaluation module  226  depending on whether the model(s) for determining the truth coefficients  514  include factors also used in determining affinity scores. Separately, a viewing agent  142  that has a close affinity for a user may be more inclined to believe claims made by that user. A viewing agent  142  that has no connection to a user&#39;s friends, on the other hand, has no reason to trust the user&#39;s friends&#39; claims about the user. As a result, truth coefficients  514  for claim objects  116  about the user&#39;s age may be highly influenced by the viewing agent&#39;s connection to the user, or affinity score for the user, as well as the lack of connections to the user&#39;s friends, in one embodiment. In turn, the claim evaluation module  226  may assign a lower truth coefficient  514  to the user&#39;s friends&#39; claims than the truth coefficient  514  for the user&#39;s claim. 
     In another embodiment, information retrieved from other objects on the social networking system  100  may be used by the claim evaluation module  226  to assign truth coefficients  514  to the claim objects  116 . In that embodiment, the social networking system  100  may make a claim about a user&#39;s age based on the information publicly available to all users of the social networking system  100 . In a further embodiment, the claim evaluation module  226  may provide all claims that are viewable by a viewing agent  142  by providing selected claim objects  516  based on the audiences for those selected claim objects  516 . In yet another embodiment, the claim evaluation module  226  may provide a claim to a viewing agent  142  based on the highest truth coefficient for the claim based on the viewing agent&#39;s connections to authors making the claims. 
     In one embodiment, heuristics analysis may be used to gather information from the social networking system  100  that may be used to evaluate claims. For example, an author may make a claim that he lives in San Francisco, Calif., while an action log  504  may record various check-in events performed by users of the social networking system  100 , including the author as well as the author&#39;s connections on the social networking system  100 , such as other users, entities, events, groups, applications, and the like. Heuristics analysis may be used to analyze claims about a user&#39;s current city in which he or she lives, as declared on the social networking system  100 , to determine how often the user is associated with a check-in event in or within 50 miles of San Francisco, Calif. This information may be used as a factor in evaluating the truthfulness of declared current city living situation claims in a model by the claim evaluation module  226 , in one embodiment. 
     Another use of heuristics analysis includes gathering and analyzing different types of information about claim objects  116  being evaluated. For example, a page representing a Chinese restaurant may make a claim that a user ordered Szechuan chicken ten times in the past month. As mentioned earlier, custom graph actions and custom graph objects may be used by an external website or application to communicate user activities performed on the external website or application back to the social networking system  100 . The claim evaluation module  226  may gather and analyze different types of claims related to this claim, such as the user claiming to like Chinese food, multiple users claiming that the user was present in a check-in event at the same Chinese restaurant represented by the page making the claim, pictures tagged with the custom graph object for “Szechuan chicken” along with a tag for the user uploaded to the social networking system  100 , and so on. Other information, such as the reputation of the page and/or application making the claim, may also be gathered and analyzed by the claim evaluation module  226 . Using the gathered information, heuristics analysis may be used to determine that the claim made by the page representing the Chinese restaurant is truthful. As a result, the claim evaluation module  226  may gather and analyze different types of information, including other claims, to evaluate the truthfulness of a particular claim made on the social networking system  100 . 
     Example Applications Using Claims in a Social Networking System 
     A social networking system  100  may utilize claim objects  116  in several different ways to provide additional services internal and external to the social networking system  100 . Such uses may include a contact card application provided by the social networking system  100  to enable agents to manage contact information about other agents on the social networking system  100 , a customer relationship management system that enables agents to indicate relationships with other agents and identify expertise levels based on recommendations by the agents, a browse and/or query system that enables agents to query claims made by agents internal and external to the social networking system, alternative business models that enable agents to be compensated for making claims and/or providing access to their claims, and so forth. Each of these uses is further described in detail below. 
     Claim-Based Profiles on a Social Networking System 
       FIGS. 6A and 6B  are example screenshots depicting a user interface for receiving and providing claims about users in a social networking system, in accordance with an embodiment of the invention. A social networking system  100  may utilize claim objects  116  in several different ways. In one embodiment, a contact card application may be provided by the social networking system  100  to enable users to manage contact information about other users on the social networking system  100 . Instead of viewing a user profile that the subject user has generated himself or herself, the viewing agent may view claims made about the subject user with respect to information accessible by the viewing agent based on the audiences associated with the claims. 
     As illustrated in  FIG. 6A , a contact card application user interface  600  includes a profile picture  602  of the subject user, a name  604  of the subject user, a persistent identifier  606  of the subject user, such as a URL, a phone number  608  for the subject user, a current city  610  of the subject user, a current employer  612  of the subject user, and a hometown  614  of the subject user. Here, Joe Schmo is the subject user. In  FIG. 6A , each of the biographical information items are associated with claim objects  116  stored in a claim store  220 . Also provided by the contact card application user interface  600  is a claim  616  that Joe has three pets, a claim  618  that the first pet is Mu who appears in a photo, a claim  620  that the second pet is Nu, and a claim  622  that the third pet is Rho. The contact card application user interface  600  also includes a claim  624  that Joe&#39;s favorite food is Pho and a recent check-in event  626  related to this favorite food claim  624 . The claims listed in the contact card application user interface  600  are configured with audiences that the viewing agent is included in. One or more of the claims listed in the contact card application user interface  600  may be a claim authored by the viewing agent, such as the favorite food claim  624 . Users of the social networking system  100  may make claims about other users through a claim composer interface  628 . Here, the claim composer interface  628  includes various tabs to create claims, post a link related to a claim, add photos related to a claim, and write a note about the claim. A text field  632  is provided within the claim composer interface  628  for receiving user input for the claim. A drop down menu  630  may provide more options for creating a claim, such as uploading a video related to a claim, requesting information from other users about a claim (such as verifying the assertion made in the claim), sending a request to authors of claims for access to claims, approving received requests for access to claims, delegating approval of access to selected users to provide access to information included in the contact card application user interface  600 , and selecting the audience to be associated with the claim. 
       FIG. 6A  includes claims having various claim types. For example, the claim  616  that “Joe has three pets” is a biographical claim type about pet ownership. In one embodiment, the social networking system  100  may identify keywords in a claim, such as “pets,” to identify the claim type of the claim being made on the social networking system  100 . As another example, the claim  624  that “Joe&#39;s favorite food is Pho” is a favorite food claim type specifying a type of food that may be represented as a custom graph object in the social networking system  100 . In one embodiment, the social networking system  100  may make a claim about a user, such as the user&#39;s favorite food, based on content items uploaded to the social networking system  100 . In another embodiment, the social networking system  100  may suggest to a user a claim based on other claims made by other users about the same subject, such as the user&#39;s favorite food. In yet another embodiment, custom graph objects, such as Pho, may be associated with other graph objects, such as noodles, that may help the social networking system  100  retrieve related content posts, such as the check-in event  626  that includes the text “Long Noodles, Long Life!” and a user tag of “Mike Atkins” at a location named “PPQ.” PPQ may be represented by a page on the social networking system  100  that serves Pho as well as other noodles. Because of the association with the custom graph object of “Pho” and attributes of the page object for “PPQ,” the check-in event  626  may be displayed in the contact card application user interface  600 . In one embodiment, the user tag of “Mike Atkins” may also be a claim. Thus, the claim that “Joe&#39;s favorite food is Pho” may rely on another claim that “Mike Atkins” was with “Joe Schmo” at “PPQ,” as illustrated by the check-in event claim  626 . 
     Different claims may be presented to a viewing agent based on whether the viewing agent is included in the audience for a claim. For example, a first viewing agent may be provided with the contact card application user interface  600  illustrated in  FIG. 6A , in which the hometown claim  614  lists “Dallas, Tex.” as the hometown of Joe Schmo. A second viewing agent may be provided with the contact card application user interface  600  illustrated in  FIG. 6B , in which the hometown claim  636  lists “Plano, Tex.” as the hometown of Joe Schmo. The subject user, Joe Schmo, may have listed “Dallas, Tex.” in his user profile as his hometown, creating the claim  614  that he is from Dallas. However, other users connected to the subject user may have claimed that Joe Schmo is actually from Plano, a suburb of Dallas. The second viewing agent may be connected to the other users making the hometown claim  636  about Joe, such that the second viewing agent is included in the audience of the hometown claim  636 . Different types of information may be gathered and analyzed to determine the best claim for the second viewing agent, such as check-in events near or in Dallas, Tex. (giving additional weight to check-in events during the holidays), a high number of user connections that list Plano, Tex. as their hometown, the number of user connections that list Dallas, Tex. as their hometown, interactions on the social networking system that indicate an interest in Dallas versus Plano (such as posting links about the city, supporting political candidates from the city, and joining groups of users with hometowns in the city), and examining other claims associated with the user (such as claims about attending a high school in the city, user connections that have claimed attending a high school in the city, etc.). As a result, the social networking system  100  may determine that the hometown claim  636  is the best claim for the second viewing agent using the claim model in the claim evaluation module  194  and provide that hometown claim  636  to the second viewing agent. 
     As illustrated in  FIG. 6B , a second viewing agent may view different claims than a first viewing agent viewing the contact card application user interface  600  illustrated in  FIG. 6A . The contact card application user interface  600  illustrated in  FIG. 6B  provides a different phone number for Joe Schmo, indicated by the phone number claim  634 . The current city claim  638  also indicates that Joe Schmo lives in Mountain View, Calif. The pet owner claim  640  indicates that Joe has two pets: a first pet claim  642  that the first pet is Moo and a second pet claim  644  that the second pet is Nyu. The second viewing agent is also presented with a different custom graph object for the favorite food claim  646 , listing “Noodles” as Joe&#39;s favorite food. The differences between the claims provided in  FIG. 6A  and the claims provided in  FIG. 6B  take into account social information retrieved about the subject user as well as information retrieved about the first and second viewing agents. For example, a second viewing agent may not be in the audience for the third pet claim  622  of the third pet named “Rho” and, as a result, may not be able to view that claim. The subject user may have only declared that he has two pets, forgetting to update his user profile after he got his third pet. Other users may have corrected the pet owner claim  640  to correctly claim that he has three pets, as provided in the first pet owner claim  616 . 
     As mentioned above, other functionality may be incorporated into the claim composer interface  628 . For example, a user may request contact information of a subject user, such as a phone number, that the user does not have access to based on not being included in the audience for the claim type that includes the subject user&#39;s phone number. In response to the request, the subject user may, without creating a connection to the requesting user, approve the request and expand the audience of the phone number claim type to include the requesting user. In another embodiment, the subject user may delegate the power to expand the audience of the phone number claim type to one or more selected users of the social networking system  100 . In a further embodiment, a requesting user may make a request for the contact information, such as physical mailing addresses, in bulk by naming users of the social networking system, regardless of whether those users are connected to the requesting user. For example, the requesting user may be the maid of honor to users that are getting married and may need to get the physical mailing addresses of the engaged users&#39; guest list for sending wedding invitations. In response to receiving a request for a physical mailing address, the subject user may or may not be connected to the maid of honor making the request. Another user connected to the subject user may be selected as a delegate to provide the requested information by making a claim about the physical mailing address of the subject user, or to provide access to the requested information by modifying the audience of the claim to include the requesting user. 
     The contact card application user interface  600  may comprise an application operating on the social networking system  100 , in one embodiment. For example, the contact card application user interface  600  may be provided on a web browser operating on a user device connected to the social networking system  100  or the contact card application user interface  600  may be provided on a native application operating on a mobile device communicating with the social networking system  100  through a series of application programming interface (API) calls. In another embodiment, the contact card application user interface  600  may be a stand-alone application operating on an external system outside the social networking system  100 . In the stand-alone application embodiment, the application may interface with several contact applications, external systems, and social networking systems to synchronize the contact information of users. In a further embodiment, the contact card application user interface  600  may operate on a mobile device and be integrated with the mobile device&#39;s operating system and contact management software. 
     Additional Uses of Claims in a Social Networking System 
     Aside from the contact card application user interface  600  illustrated in  FIGS. 6A and 6B , the social networking system  100  may use claim objects  116  in various ways to provide information about users of the social networking system. For example, a lightweight customer relationship management (CRM) system may be provided by the social networking system  100  by enabling users to compose notes about other users on the social networking system  100 . In one embodiment, a user trying to promote a product or sell a service may make notes about certain users that have interacted with the product or service, such as “contacted this user and the user agreed to forward the link to his friends.” Claims may also be used to affect agent reputation in work experiences. For example, a user may note that he had a good experience working with another user and claim that the subject user is a “hard worker.” Claims about work experiences may be used in hiring decisions by other users of the social networking system  100 , in one embodiment, if the claims made about users are provided to employers requesting access to the claims. These claims may be captured as “notes” attached to a user&#39;s contact card. Notes may also use structured information, such as a ratings scale or a prompt asking “Would you recommend this person/service?” that may be associated with the subject agent. 
     Claims may also be used to determine whether an agent may be an expert in a topic, such as cooking, music, home décor, and sports, in one embodiment. For example, if multiple agents claim that a particular user is an expert at cooking, that particular user may be designated as an expert. An expert may be defined as a subject agent that has one or more claims by authoring agents having an assertion about a subject, where the assertion is the agent has an expertise in the subject. The level of expertise may be determined by the number of claims made about the subject agent as well as the strength of each assertion in the claims about the subject agent. The strength of an assertion may be determined by the social networking system  100  based on keywords, capitalization, fonts, and photographs used in making the claims. For example, the claim that “John is a GREAT cook” and others like it may reinforce the expert knowledge of John and cooking. Similarly, the claim that “Betsy makes killer deviled eggs” that is posted with a picture of the deviled eggs, as well as social validation around the content post and other similar claims by others about Betsy&#39;s cooking provides credibility to the claim that Betsy is an expert cook. Meanwhile, if only one agent makes a claim about a subject user and their expertise and that agent has a high affinity for the subject user, the strength of the claim may be questionable. For example, if an authoring agent stated that “Michelle bakes yummy cookies” and there were no other claims about Michelle&#39;s cooking made by other agents, then the claim confidence for the assertion that Michelle is a good cook is relatively low. If that claim was made by an authoring agent that has a high affinity for Michelle, then the claim may have a discount, in one embodiment. Other content items, such as photos of food cooked, as well as the factors outlined above, including frequency of claims about cooking, total number of claims about the assertion, and implied claims based on trusted connections&#39; claims, may be used in determining whether agents may be classified as an expert. As a result, claims made by an expert may have an “expert adjustment” such that the truth coefficients for claims made by the expert in the topic of their expertise have a higher truth coefficient than non-experts. Claims related to the expert&#39;s topic may be trusted more if they are made by an expert. For example, if an expert in cooking makes the claim that “Basil is the most important ingredient in spaghetti sauce,” in an application for sharing recipes, then that claim may be given a higher trust coefficient, or truth coefficient, by the social networking system  100 . In another embodiment, the trust coefficient may be increased based on the strength of the expertise of the expert which may be determined based on claims made about the expert in relation to the subject. In other words, a trust coefficient for the assertion that the agent is an expert may be determined based on claims made about the agent in relation to the assertion by other agents in the social networking system  100 . 
     Derivative Claims 
     Derivative claims may also be generated by the social networking system  100  based on claims made by agents. Because the social networking system is included in the audience of every claim, the social networking system may generate derivative claims based on claims made by agents. For example, the social networking system may make a derivative claim that Bob claimed that Joe is an Expert at Cooking. As a result, the social networking system may create a targeting cluster that includes all agents that are users that have been claimed to be Experts at Cooking for targeting advertisements about a new line of pots and pans. In this way, the derivative claim does not violate privacy settings of the author of the base claim. 
     Other types of derivative claims may be made by the social networking system  100  as well as agents on the social networking system  100  for other purposes, such as generating and publishing visualizations of claims on timelines of agents that help users read claims more efficiently and create more engagement around claims, insights that distill information across a set of agents that help agents better understand the activity on the social networking system  100 , target messaging and advertising, and refine search. Derivative claims may not have audiences larger than the audiences indicated in the base claims to protect the privacy of agents. Derivative claims may also be generated and used by the social networking system  100  to improve the user experience of the social networking system  100 . For example, an algorithm that determines a probability that a first user knows a second unconnected user on the social networking system  100  may generate a derivative claim based on claims about the first and second users, such as common friends, interests, groups, events, connections to entities, applications, and pages, as well as educational and work experience. The generated derivative claim may have a determined truth coefficient that may be factored into the algorithm that determines the probability that the first user knows the second unconnected user in the social networking system  100 . Claims made about a particular user by agents in the social networking system  100  are associated with a user profile object for the particular user, in one embodiment. 
     Claims made about users, such as claims made by an application for taking orders for a Chinese restaurant, may be aggregated and used as a derivative claim for targeting advertisements to users based on the claims. For example, the social networking system may generate a derivative claim of all users that have ordered food from the Chinese restaurant in the past week, generate a targeting cluster of users based on the derivative claim, and enable advertisers to select that targeting cluster based on keywords or keyword phrases related to “Chinese food.” 
     In addition to targeting advertisements, the social networking system may use derivative claims to enhance the experience of users and entities, such as generating better predictions of unconnected users that a viewing agent may know and wish to connect with, providing better photo recognition of subject agents tagged in photos based on derivative claims that aggregate all claimed tags of the subject agents, enabling a more relevant search algorithm to rank search results using derivative claims about the terms in the search query, generating visualizations of claims made about a subject agent in a timeline for the subject agent based on derivative claims, and so on. 
     Derivative claims may be generated by a social networking system  100  based on claims generated by users, entities, groups, and events on the social networking system  100 . For example, a visualization claim may be generated by the social networking system  100  to capture the claims that were generated by all users of the social networking system  100  that are publicly available that are related to a response to a sudden death of a public figure, such as Steve Jobs. Visualizations may be published to a timeline of the subject agent based on the privacy control settings of the subject agent, in one embodiment. In another embodiment, visualizations may be published on the timeline of the subject agent upon receiving consent from the subject agent. In a further embodiment, visualizations may be made anonymous by aggregating the claims and generating a derivative claim based on the claims about the subject user. For example, a visualization of how many users claimed that Steve Jobs changed their lives may be posted on a page in the social networking system  100  for Steve Jobs based on claims made by users related to Steve Jobs. 
     Visualizations may be generated by the social networking system  100  as derivative claims to be posted on timelines of agents of the social networking system  100 . A social networking system  100  may post a claim about an agent on the agent&#39;s timeline if the agent is a member of the audience for the claim and if the agent chooses to allow the post on their timeline. Any claim that the agent authored or in which they are referenced by a link or tag may be posted on the agent&#39;s timeline. A timeline may have four primary axes of representation: temporal, spatial, social (organized by social relationships using the signifier “with”), and categorical (e.g., favorite bars in SF, album of a trip to Europe). As another example of a post on an agent&#39;s timeline, the social networking system may generate a visualization of favorite bars visited in the last month based on check-in events of a subject user as well as other users connected to the subject user providing check-in information. Even if the subject user does not check-in to a bar, because his friends check-in to the bar with the subject user, that bar may move up the list in relevance in the favorite bars visualization. In another embodiment, rankings of the bars visited in the past year may be based on claims generated by external systems, such as third-party applications providing location information of the subject user. The social networking system  100  may generate a derivative claim based on the received check-in events and location information supplied by third-party applications that the subject user has favorite bars located in a certain area of the city. Time and date information may also be used to generate visualizations, such as favorite happy hour bars, based on claims made about the subject user. In yet another embodiment, a visualization may be generated based on claims made about all users in the local city location with similar demographics. In a further embodiment, a visualization may be generated using affinity score information of users as well as demographics. In yet another embodiment, the social networking system  100  may generate visualizations based on derivative claims for use in advertisements. 
     A social networking system  100  may generate derivative claims in order to generate truth coefficients and prompt a viewing agent for feedback without violating privacy control settings. In one embodiment, a social networking system  100  may generate one or more derivative claims based on multiple claims authored by agents about a subject. For example, the social networking system  100  may generate a derivative claim that Joe and Mary claim that Bob&#39;s mobile number is 123-456-7890 and that Peter and Paul claim that Bob&#39;s mobile number is 415-867-5309. The viewing agent, Sam, may claim that the number provided by Peter and Paul is Bob&#39;s mobile number. Each of the claims by Joe, Mary, Peter, and Paul may have one or more truth coefficients that exceed a minimum predetermined threshold of truthfulness because Bob may have more than one mobile number, such as a personal mobile number and a work mobile number. As a result, the viewing agent may be prompted to give feedback about the number claimed by Joe and Mary. If the viewing agent verifies that the number claimed by Joe and Mary is also a valid number, such as by adding that number into the viewing agent&#39;s address book or otherwise selecting that number, then the social networking system  100  may accord that number as being truthful, providing useful feedback to the social networking system  100  in calculating the truth coefficients for the two claims. 
     Browse Layer for Claims 
     A social networking system may also implement a claims browser user interface in which a viewing agent may search all claims that they can see, or any claim in which the viewing agent is a member of the audience on the social networking system. A claims browser user interface enables a viewing agent to submit a search query which may return an “exact match” for claims, such as “where does Sam say Sam attended school, who attended Harvard according to Harvard, and who says they like Lady Gaga.” In this way, the “exact match” query provides a search result for specific claims made about the search terms in the query. In contrast, the claims browser may also enable a search query to perform a “best match” search, such as “who attended Harvard and who likes Lady Gaga.” In that instance, the “best match” query returns a search result that may include other claims, in addition to specific claims matching the search terms, such as derivative claims generated by the social networking system as well as claims by authors other than the subject agent that are relevant to the search terms. For example, a subject agent may not specifically claim they attended Harvard, but the authoring agent Harvard may claim that the subject agent attended Harvard. Similarly, a subject agent may not specifically claim that they like Lady Gaga, but the social networking system may generate a derivative claim based on other claims made by the subject agent and other agents that indicate that the subject agent likes Lady Gaga, such as custom graph actions performed on custom graph objects including listening to songs by Lady Gaga, purchasing merchandise by Lady Gaga, and playing games associated with Lady Gaga. Other actions performed by other agents may also indicate an interest in Lady Gaga by the subject agent, such as being tagged in a photo at a Lady Gaga concert, a number of connected agents sharing content items about Lady Gaga, and viewing external websites connected to the social networking system that are relevant to Lady Gaga, where the viewing agent has opted in to sharing browsing information with the social networking system. As a result, the “best match” search may provide more relevant search results based on claims and predictions generated based on claims. 
     The search results may be “pushed” to a user when they change or become updated. A viewing agent that may want to know which connections are interested in Lady Gaga may be updated through a push notification on the social networking system or through another communications method, such as messages, chat, email, and the like. Claims searching may also be integrated with other products and services on the social networking system, such as automatically updating a dynamic ticker with search results of new users that have claimed to attend the same college or university as a viewing agent, newsfeed stories of “best match” claims that may be of interest to the viewing agent, and new applications that may utilize claims information about the viewing agent that may be presented via a suggestion or advertisement. The results of a claims query may be provided to a viewing agent through a website, on a mini web applet, a mobile device, or through an application programming interface (API). Notifications of when a definable event occurs, such as when a certain threshold number of claims is reached, may also be packaged and sold to customers wishing to receive the notifications. 
     Business Models Using Claims 
     In one embodiment, an author may pay the social networking system to boost the rankings of the author&#39;s claims in a query for “best match” claims. In another embodiment, an agent may pay the social networking system to boost a particular claim in the ranking for “best match” claims. In a further embodiment, an agent may define an exact, or “best match” set of agents to boost a particular claim such that the particular claim is boosted for that set of agents. In yet another embodiment, an agent may pay to boost classes of stories by others, based on historical claims and truth coefficient of an author. 
     In a further embodiment, a social networking system may pay agents for generating engagement and impressions of content on the social networking system. For example, agents may embed claim queries in any format on third-party applications and/or external systems that drive traffic and engagement to the social networking system. In addition, the embedded claim queries may help the social networking system optimize what content is provided to agents on the social networking system, such as through a news feed, notifications, rankings, and advertisements. The social networking system may also pay agents based on developing claims that provide more information to the social networking system to improve targeting as well as claim queries. 
     A social networking system may also be compensated for insights and/or feeds of information that third-party advertisers, developers, and administrators may want to process and monetize. For example, sophisticated claim queries may be formulated to enable an advertiser to identify users that may be having a baby in the near future. By providing timely information based on claims authored by agents on the social networking system, advertisers may use this information to better target users without sacrificing the privacy of the users. 
     Claims may also be integrated into existing services and features on the social networking system, such as connection requests between agents, adding elements to lists for display on an agent&#39;s profile, page, or application, and enabling applications to publish claims on behalf of an agent. For example, an initiating agent makes a claim that they are friends with a target agent. This claim has a privacy limit/audience set by the initiating agent. The claim is delivered to the target agent based on a “best match” claim query of “friendship requests target would be interested in.” The social networking system may provide a simple interface for the target agent to claim friendship with the initiating agent. If both agents make reciprocal claims, then the privacy limit of the friendship is lifted. As another example, an agent may authorize an application to create a custom list on behalf of the agent. For example, a list of top food items ordered at a restaurant, based on claims made by agents as well as custom graph actions transmitted to the social networking system from a food ordering system, may be generated by the application and updated based on newer information. As a result, the application is generating derivative claims of the “top items” based on other claims made by agents or authorized by agents. 
     Address Book Using Claims 
     In a further embodiment, a stand-alone application may be created using claims generated within the social networking system  100 . For example, a stand-alone address book application may enable synchronization of contact information for an agent&#39;s contacts, such as a user&#39;s friends and friends of friends. A synced claim may be passed by the social networking system  100  to a synced system external to the social networking system  100 , such as one or more content delivery networks (CDNs), browser applications, third-party mobile address books, and a third-party contact management system. A user may enable third-party applications that manage the user&#39;s contacts to connect with the stand-alone address book application such that the third-party applications are agents making claims about the user&#39;s contacts&#39; information, including phone numbers, email addresses, physical addresses, employers, titles, and so on. In one embodiment, particular types of contact information may be synced by the social networking system  100  based on agreements with the administrators of the third-party applications and/or synced systems. In another embodiment, agents may not be given the ability to prevent or limit syncing claims separately from defining the audiences of the claims. The stand-alone application may use the claim query functionality described above in searching claims for contacts. In this way, the stand-alone application is collaboratively maintained by all agents making claims about contact information for target users and/or entities. The stand-alone application may also be implemented on an external system on the Internet, as well as an m-site implementation and on native iOS and Android applications. The stand-alone address book application may be integrated into various chat, email, and messaging platforms, such as FireFly Talk, Facebook Messaging, Gmail, Yahoo Mail, Outlook, Hotmail, and the like. Based on claim queries, such as “best match” claim queries, the stand-alone address application may suggest improvements and changes to claims made by an agent. No privacy settings can prevent an agent from adding information to their address book, provided by the stand-alone address application, as long as the information is accessible to the agent. Other agents cannot override an authoring agent&#39;s claims without the explicit consent of the authoring agent. 
     The stand-alone application may enable an agent to perform actions on claims, or attributes, listed on a contact card, such as call, email, message, and invite. From the stand-alone application, the viewing agent may call a phone number claimed for a target agent. Notes may also be attached to a contact card for a target agent. Reviews are a special type of note that may be attached to a contact card that includes more structure, such as a rating of the contact, a response to the question “Would recommend?,” optional questions provided by entities associated with the contact card, such as “Is this restaurant romantic” or “Was the service good?,” a free text field, and an audience selector. A history may be attached to a contact card, displaying an audit trail related to the card. Logged events include attribute changes and actions. The stand-alone application may be initially populated with an agent&#39;s existing connections on the social networking system, including existing connections to users and liked pages. 
     Missing attributes may be automatically filled with “best guess” claims from contacts and friends. “Best guess” claims may be derivative claims generated based on claims made by agents on the social networking system  100 . When conflicting changes are made to a contact&#39;s attributes by the contact or by connected users, the agent may be notified of the change inline on the card and prompted with whether the agent would like to update the contact card accordingly. Missing attributes may also be requested from the contact or from mutual friends by the agent. If the requestee sends the contact information and the information is already in the stand-alone application, then the audience of the contact information is increased to the previous audience plus the requestor. If the contact information did not previously exist in the stand-alone application, then the requestee is asked to fill in the contact information (i.e., generate a claim) and assign an audience to the new claim which must include the requestor. Contact cards may be shared with a recipient. A shared contact card includes all of the author&#39;s claims and any claims to which the recipient has access. In one embodiment, a viewing agent may ask other agents connected to the viewing agent in the social networking system, through the stand-alone application, for contact information about a target contact. For example, contact information of a contact, “Joe Schmo,” such as his mobile phone number, may be asked by a viewer of the stand-alone application running the application on an iOS device. The viewer may select one or more connections on the social networking system who may know “Joe Schmo.” In one embodiment, the social networking system may search for agents that are connected to the viewer on the social networking system as well as the target contact “Joe Schmo” and list the results. In another embodiment, the viewer may simply query the stand-alone application for the contact information of “Joe Schmo,” even if the viewer is not connected to Joe Schmo in the real world. The results of the query may result in the contact information, if the viewer is in the audience of the claims that include the contact information. In a further embodiment, the results of the query may result in a prompt to one or more connections of the viewer that are also connected to the target contact to share the requested contact information with the viewer. 
     The stand-alone application may automatically generate a claim based on an action by an agent. For example, if a viewing agent uses a source agent&#39;s claim, such as making a phone call, e-mailing an agent, and getting directions to an agent&#39;s house, then the source agent&#39;s claim is copied with the viewing agent making the claim and a default privacy setting, or audience, of just the viewing agent. These claims may be “bolded” in the stand-alone application or otherwise highlighted to indicate the automatic generation of these claims. The viewing agent may later assign a new audience for these types of claims. 
     Within the stand-alone application, a viewing agent may view claims made by other agents about a particular contact, such as a mobile number for the contact. A viewing agent may select multiple claims for the mobile number of a contact based on the claims made by other agents and selected multiple check boxes. In doing so, the viewing agent is claiming that the contact has more than one mobile number and may re-label each mobile number with a different name, such as personal mobile and work mobile. A viewing agent may also copy a claim for a mobile number into a new claim, according to whether the author of the claim has enabled the viewing agent to copy the claim through the one or more copyright bits. For example, an authoring agent may represent a company with numerous sales contacts, including names, emails, and phone numbers. The authoring agent may wish to import the numerous sales contacts into the stand-alone application such that the audience of the sales contacts is limited to the authoring agent and a relatively few number of other agents, such as sales team members. In that instance, the authoring agent may enable the audience of the other sales team agents to copy the claim into a new claim. 
     The stand-alone application may also, in one embodiment, operate on the social networking system  100 , such that the social networking system  100  may provide a service to agents requesting information about a specific person, such as whether the specific person is trustworthy, non-malicious, and the like. The social networking system  100  may also, while respecting the privacy of authoring agents, enable agents of the social networking system  100  to sell access to information to each other. This business model would enable agents to modify the one or more copyright bits to include other agents that have paid for access to the information included in the claims authored by the agents. In this instance, paid access to claims would produce claims that are not copyable, but only viewable by the paying agents where the claims which access was paid for automatically modify the audiences of the claims to include the paying agents. For some types of information, such as sensitive data, an agent that imports such information to the stand-alone application or pays for access to such information may be responsible for ensuring that the privacy of the subject agents is maintained. 
     In a further embodiment, a claim may only be authored by an agent if the agent was paid to make the claim. For example, an agent may only check-in at a restaurant if the agent were paid to make that claim. The social networking system may provide a marketplace or auction through which agents may offer their claim authoring abilities to other agents in exchange for a payment. By checking into the restaurant, the agent will broadcast the claim that the agent is at the restaurant to other agents connected to the authoring agent. In another embodiment, the social networking system may provide a premium service to validate whether an agent is a real person, a real entity, or has a valid email address. Users of the validation service may make a payment, such as a one-time payment or a subscription method of payment, in exchange for validation of an agent, by name or email address. 
     In other embodiments, the social networking system may record top-level domain names of websites visited by agents of the social networking system and store those visits as custom graph actions and custom graph objects in an activity log on the social networking system. In this way, the social networking system may generate derivative claims about agents of the social networking system to identify top websites visited by the agents over a certain time period. Because agents are generating the original claim by visiting the websites, the website visiting agents are owner agents of the claims generated by visiting the websites and may remove the visits and block visits from being recorded in the activity log, in one embodiment. 
     Business Models and Functionality Using the Claim and Warehouse Layers 
     A social networking system  100  may monetize the storage capability of the warehouse layer by providing a software-as-a-service (SaaS) social graph to potential customers. In one embodiment, raw storage may be sold at the warehouse level and a SaaS social graph may also be sold at the claim layer, utilizing the identity model of the claim layer. In another embodiment, “cloud file-conversion” as a service may also be provided by the social networking system  100 , enabling customers to convert their files in a distributed computing environment enabled by the warehouse layer. 
     The social networking system  100  may leverage its role as a participant in the claim layer by authoring claims as an agent and as an application. The social networking system  100  may aggregate insights, such as publishing anonymous trends to various audiences, including advertisers. The social networking system  100  may also merge various objects by generating “equality” claims, or claims signifying that two objects are equivalent. This helps to increase efficiency. Other agents may also generate equality claims, such as identifying products by barcodes, uniform product codes (UPCs), or other identifiers. A social networking system  100  may also generate suggestions to specific agents, such as suggestions to connect with other agents (people you may know) where each claim has an audience that only includes each specified agent. 
     A social networking system  100  may also generate claims to identify real users with authenticated identities based on email address verification. These claims may then be packaged as a list of authenticated identities and sold via APIs to advertisers and/or third parties. The social networking system  100  may also act as a proxy to enable a third party to match contact information of users with user identifiers using a hashed identifier provided by the social networking system  100 . The social networking system  100  may ensure the integrity of the privacy model by acting as a proxy between potential customers and the agents of the social networking system  100 . A social networking system  100  may also utilize any of the above-mentioned business models provided to other agents and/or applications in the social networking system  100 . 
     SUMMARY 
     The foregoing description of the embodiments of the invention has been presented for the purpose of illustration; it is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Persons skilled in the relevant art can appreciate that many modifications and variations are possible in light of the above disclosure. 
     Some portions of this description describe the embodiments of the invention in terms of algorithms and symbolic representations of operations on information. These algorithmic descriptions and representations are commonly used by those skilled in the data processing arts to convey the substance of their work effectively to others skilled in the art. These operations, while described functionally, computationally, or logically, are understood to be implemented by computer programs or equivalent electrical circuits, microcode, or the like. Furthermore, it has also proven convenient at times, to refer to these arrangements of operations as modules, without loss of generality. The described operations and their associated modules may be embodied in software, firmware, hardware, or any combinations thereof. 
     Any of the steps, operations, or processes described herein may be performed or implemented with one or more hardware or software modules, alone or in combination with other devices. In one embodiment, a software module is implemented with a computer program product comprising a computer-readable medium containing computer program code, which can be executed by a computer processor for performing any or all of the steps, operations, or processes described. 
     Embodiments of the invention may also relate to an apparatus for performing the operations herein. This apparatus may be specially constructed for the required purposes, and/or it may comprise a general-purpose computing device selectively activated or reconfigured by a computer program stored in the computer. Such a computer program may be stored in a non-transitory, tangible computer readable storage medium, or any type of media suitable for storing electronic instructions, which may be coupled to a computer system bus. Furthermore, any computing systems referred to in the specification may include a single processor or may be architectures employing multiple processor designs for increased computing capability. 
     Embodiments of the invention may also relate to a product that is produced by a computing process described herein. Such a product may comprise information resulting from a computing process, where the information is stored on a non-transitory, tangible computer readable storage medium and may include any embodiment of a computer program product or other data combination described herein. 
     Finally, the language used in the specification has been principally selected for readability and instructional purposes, and it may not have been selected to delineate or circumscribe the inventive subject matter. It is therefore intended that the scope of the invention be limited not by this detailed description, but rather by any claims that issue on an application based hereon. Accordingly, the disclosure of the embodiments of the invention is intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims.