# Patent

## Title
Predicting user navigation events in a browser using directed graphs

## Abstract

A method and system for predicting a next navigation event are described. Aspects of the disclosure minimize the delay between a navigation event and a network response by predicting the next navigation event. The system and method may then prerender content associated with the next navigation event. For example, the method and system may predict a likely next uniform resource locator during web browsing to preemptively request content from the network before the user selects the corresponding link on a web page. The methods describe a variety of manners of predicting the next navigation event, including examining individual and aggregate historical data, text entry prediction, and cursor input monitoring.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of U.S. patent application Ser. No. 13/233,300, filed Sep. 15, 2011, the disclosure of which is incorporated herein by reference.


BACKGROUND
The advent of the World Wide Web has placed more information at the fingertips of today's users than ever before. Various websites cater to nearly every need and interest, providing access to reference information, business and financial documents, social networking, and more. Widespread broadband Internet access provides faster access to these sites than ever before.
However, as fast as current high-speed Internet services are, the act of browsing the web is not instantaneous. When a user selects a link on a page or enters a uniform resource locator (URL) in a text field, there is a delay while data is requested from the host, sent to the client, and rendered in the browser. The user may be idle while waiting for their requested site to load. While high-speed Internet access may limit this delay to a few seconds, even this short delay can add up to thousands of man-hours of lost productivity each year.
BRIEF SUMMARY
A method and system for predicting user navigation events are described. Aspects of the disclosure minimize the delay in accessing web content by predicting a user navigation event on a web page. The navigation event may be predicted by various indicators, including but not limited to a user's navigation history, aggregate navigation history, text entry within a data entry field, or a mouse cursor position. Users can be provided with an opportunity to opt in or out of functionality that may collect personal information about them. In addition, certain data can be anonymized and aggregated before it is stored or used, such that personally identifiable information is removed.
Aspects of the disclosure provide a computer-implemented method for predicting a user navigation event. The method may include storing a set of navigation data, the navigation data comprising at least one directed graph, where at least one vertex of the directed graph comprises at least one navigation event and an edge of the directed graph is weighted by a count value representing a number of times a navigation has occurred from a source vertex to a destination vertex coupled thereto by the edge, identifying a current navigation history, the current navigation history comprising one or more previous navigation events accessed in a browser, mapping the current navigation history, using a processor, to the at least one directed graph within the set of navigation data, determining a confidence value for a given navigation event using the at least one directed graph, and identifying the given navigation event as a likely navigation event based on the confidence value, such that the likely navigation event is configured to be utilized by the browser to assist with navigation operations. The at least one directed graph may be keyed to at least one previous navigation event in the current navigation history. The at least one previous navigation event may be identified in an order each of the at least one previous navigation events were visited. The method may also include identifying n previous navigation events in the current navigation history, and determining which of the at least one directed graphs is keyed to the n previous navigation events. The confidence value may be weighted by at least a depth of the at least one directed graph. The weight of the directed graph may be determined by a formula graph_depthN*samples_in_graph, wherein graph_depth is the depth, samples_in_graph is a number of navigation events stored in the graph, and N is a numerical value used to adjust the significance of the graph_depth term in the weight calculation. The method may also include prerendering the likely navigation event. The browser may be a web browser.
Aspects of the disclosure also provide a non-transitory computer-readable storage medium comprising instructions that, when executed by a processor, cause the processor to perform a method. The method executed by the processor may include storing a set of navigation data, the navigation data comprising at least one directed graph, where at least one vertex of the directed graph comprises at least one navigation event and an edge of the directed graph is weighted by a count value representing a number of times a navigation has occurred from a source vertex to a destination vertex coupled thereto by the edge, identifying a current navigation history, the current navigation history comprising one or more previous navigation events accessed in a browser, mapping the current navigation history to the at least one directed graph within the set of navigation data, determining a confidence value for a given navigation event using the at least one directed graph, and identifying the given navigation event as a likely navigation event based on the confidence value, such that the likely navigation event is configured to be utilized by the browser to assist with navigation operations. The at least one directed graph may be keyed to at least one previous navigation event in the current navigation history. The at least one previous navigation event may be identified in an order each of the at least one previous navigation events were visited. The method executed by the processor may also include identifying n previous navigation events in the current navigation history, and determining which of the at least one directed graphs is keyed to the n previous navigation events. The confidence value may be weighted by a depth of the at least one directed graph. The method executed by the processor may also include prerendering the likely navigation event.
Aspects of the disclosure also provide a processing system for predicting a user navigation event. The processing system may include at least one processor, and a memory, coupled to the processor, for storing a set of navigation data, the navigation data comprising at least one directed graph, where at least one vertex of the directed graph comprises at least one navigation event and an edge of the directed graph is weighted by a count value representing a number of times a navigation has occurred from a source vertex to a destination vertex coupled by the edge. The processor may be configured to identify a current navigation history, the current navigation history comprising one or more previous navigation events accessed in a browser, map the current navigation history to the at least one directed graph within the set of navigation data, determine a confidence value for a given navigation event using the at least one directed graph, and identify the given navigation event as a likely navigation event based on the confidence value, such that the likely navigation event is configured to be utilized by the browser to assist with navigation operations. The browser may be configured to prerender the likely navigation event. The at least one directed graph may be keyed to at least one previous navigation event in the current navigation history. The at least one previous navigation event may be identified in an order each of the at least one previous navigation events were visited. The processor may be further configured to identify n previous navigation events in the current navigation history, and determine which of the at least one directed graphs is keyed to the n previous navigation events. The confidence value may be weighted by a depth of the at least one directed graph. The browser may be a web browser.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a system diagram depicting an example of a server in communication with example client devices in accordance with aspects of the disclosure.
FIG. 2 is block diagram depicting an example of a computing device in accordance with aspects of the disclosure.
FIG. 3 is a flow diagram depicting an example of a method for prerendering a web page based upon a predicted navigation event in accordance with aspects of the disclosure.
FIG. 4 is a flow diagram depicting an example of a method for predicting a navigation event based on a client navigation history in accordance with aspects of the disclosure.
FIG. 5 is a flow diagram depicting an example of a method for computing a confidence value for a URL using a client navigation history in accordance with aspects of the disclosure.
FIG. 6 is a flow diagram depicting an example of a method for predicting a navigation event based on an aggregate navigation history in accordance with aspects of the disclosure.
FIG. 7 is a flow diagram depicting an example of a method for computing a confidence value for a URL using an aggregate navigation history in accordance with aspects of the disclosure.
FIG. 8A is a flow diagram depicting an example of a method for predicting a navigation event based on an aggregate navigation history using hash values to anonymously manage link data in accordance with aspects of the disclosure.
FIG. 8B is an illustration of an example of a web browser employing an example method for predicting a user navigation event based on an aggregate navigation history in accordance with aspects of the disclosure.
FIG. 9 is an illustration of a directed graph for storing a navigation history in accordance with aspects of the disclosure.
FIG. 10 is an illustration of an example of a method for building a directed graph in accordance with aspects of the disclosure.
FIG. 11 is an illustration of an example of a method for predicting a navigation event using a directed graph in accordance with aspects of the disclosure.



DETAILED DESCRIPTION
Embodiments of a system and method for predicting user navigation events are described herein. Aspects of this disclosure minimize the delay between a navigation event and a network response by predicting the next navigation event. The system and method may prerender content associated with the next navigation event. For example, the method and system may predict a likely next uniform resource locator during web browsing to preemptively request content from the network before the user selects the corresponding link, thus reducing or eliminating the wait time when a user selects a hyperlink on a web page. Various methods describing a variety of manners of predicting the next navigation event, including examining individual and aggregate historical data, text entry prediction, and cursor input monitoring, are described. Aspects of the disclosure also relate to the prediction of the immediate user navigation (e.g., the next link the user is likely to select when viewing a particular web page, such as within the next 30 seconds, the next minute, or the next 5 minutes).
As shown in FIG. 1, an example system 102 in accordance with one embodiment includes a server 104 in communication (via a network 112) with one or more client devices 106, 108, 110 displaying web browser interfaces 114, 116, 118, respectively.
The client devices 106, 108, 110 are configured to perform prerendering operations during the execution of a web browser application. The server 104 may transmit navigation history data to the client devices 106, 108, 110, to enable prediction of a next navigation event. In some aspects, the client devices 106, 108, 110 determine a next navigation event using a local navigation history and generate a web request to the server 104 to prerender the content associated with the next navigation event. For example, the user of the client device 106 may browse to a web page located at “www.a.com” as displayed on the web browser interface 112. That page includes content selectable by the user. Based on the user's navigation history, the client device 106 may determine which of the selectable content the user is likely to select, and then prerender the content associated with the selectable content by requesting the content from the server 104.
As another example, the client device 108 may display www.a.com within a browser 114. The client device 108 may receive an aggregate set of navigation statistics from the server 104, and then determine which selectable content the user is likely to select based upon the aggregate set of navigation statistics. As yet another example, the client device 110 may display www.a.com within a browser 116. The client device 108 may determine which selectable content the user is likely to select based upon a cursor position within the browser 114.
While the concepts described herein are generally discussed with respect to a web browser, aspects of the disclosure can be applied to any computing node capable of managing navigation events over a network, including a server 104.
The client devices 106, 108, 110 may be any device capable managing data requests via a network 112. Examples of such client devices include personal computers, personal digital assistants (“PDA”): tablet PCs, netbooks, laptops, etc. Indeed, client devices in accordance with the systems and methods described herein may comprise any device operative to process instructions and transmit data to and from humans and other computers including general purpose computers, network computers lacking local storage capability, etc.
The client devices 106, 108, 110 are operable to predict navigation events to assist in data access via the network 112. For example, the client devices may predict a likely navigation event to facilitate prerendering of a web page in order to improve the user's browsing experience. In some aspects, the server 104 provides navigation data that may be used by the client devices 106, 108, 110 to predict a likely navigation event (see FIGS. 6-8). In some aspects, the client devices 106, 108, 110 predict a likely navigation event using local data. (see FIGS. 3-5, 9-11).
The network 112, and the intervening nodes between the server 104 and the client devices 106, 108, 110, may comprise various configurations and use various protocols including the Internet, World Wide Web, intranets, virtual private networks, local Ethernet networks, private networks using communication protocols proprietary to one or more companies, cellular and wireless networks (e.g., Wi-Fi), instant messaging, hypertext transfer protocol (“HTTP”) and simple mail transfer protocol (“SMTP”), and various combinations of the foregoing. It should be appreciated that a typical system may include a large number of connected computers.
Although certain advantages are obtained when information is transmitted or received as noted above, other aspects of the system and method are not limited to any particular manner of transmission of information. For example, in some aspects, information may be sent via a medium such as an optical disk or portable drive. In other aspects, the information may be transmitted in a non-electronic format and manually entered into the system.
Although some functions are indicated as taking place on the server 104 and other functions are indicated as taking place on the client devices 106, 108, 110, various aspects of the system and method may be implemented by a single computer having a single processor. It should be appreciated that aspects of the system and method described with respect to the client device may be implemented on the server, and vice-versa.
FIG. 2 is a block diagram depicting an example of a computing device 200, such as one of the client devices 106, 108, 110 described with respect to FIG. 1. The computing device 200 may include a processor 204, a memory 202 and other components typically present in general purpose computers. The memory 202 may store instructions and data that are accessible by the processor 204. The processor 204 may execute the instructions and access the data to control the operations of the computing device 200.
The memory 202 may be any type of memory operative to store information accessible by the processor 120, including a computer-readable medium, or other medium that stores data that may be read with the aid of an electronic device, such as a hard-drive, memory card, read-only memory (“ROM”), random access memory (“RAM”), digital versatile disc (“DVD”) or other optical disks, as well as other write-capable and read-only memories. The system and method may include different combinations of the foregoing, whereby different portions of the instructions and data are stored on different types of media.
The instructions may be any set of instructions to be executed directly (such as machine code) or indirectly (such as scripts) by the processor 204. For example, the instructions may be stored as computer code on a computer-readable medium. In that regard, the terms “instructions” and “programs” may be used interchangeably herein. The instructions may be stored in object code format for direct processing by the processor 204, or in any other computer language including scripts or collections of independent source code modules that are interpreted on demand or compiled in advance. Functions, methods and routines of the instructions are explained in more detail below (see FIGS. 3-11).
Data may be retrieved, stored or modified by processor in accordance with the instructions. For instance, although the architecture is not limited by any particular data structure, the data may be stored in computer registers, in a relational database as a table having a plurality of different fields and records, Extensible Markup Language (“XML”) documents or flat files. The data may also be formatted in any computer readable format such as, but not limited to, binary values or Unicode. By further way of example only, image data may be stored as bitmaps comprised of grids of pixels that are stored in accordance with formats that are compressed or uncompressed, lossless (e.g., BMP) or lossy (e.g., JPEG), and bitmap or vector-based (e.g., SVG), as well as computer instructions for drawing graphics. The data may comprise any information sufficient to identify the relevant information, such as numbers, descriptive text, proprietary codes, references to data stored in other areas of the same memory or different memories (including other network locations) or information that is used by a function to calculate the relevant data.
The processor 204 may be any suitable processor, such as various commercially available general purpose processors. Alternatively, the processor may be a dedicated controller such as an application-specific integrated circuit (“ASIC”).
Although FIG. 2 functionally illustrates the processor and memory as being within a single block, it should be understood that the processor 204 and memory 202 may comprise multiple processors and memories that may or may not be stored within the same physical housing. Accordingly, references to a processor, computer or memory will be understood to include references to a collection of processors, computers or memories that may or may not operate in parallel.
The computing device 200 may be at one node of the network and be operative to directly and indirectly communicate with other nodes of the network. For example, the computing device 200 may comprise a web server that is operative to communicate with client devices via the network such that the computing device 200 uses the network to transmit and display information to a user on a display of the client device.
In some examples, the system provides privacy protections for the client data including, for example, anonymization of personally identifiable information, aggregation of data, filtering of sensitive information, encryption, hashing or filtering of sensitive information to remove personal attributes, time limitations on storage of information, and/or limitations on data use or sharing. Data can be anonymized and aggregated such that individual client data is not revealed.
In order to facilitate the navigation event prediction operations of the computing device 200, the memory 202 may further comprise a browser 206, a navigation prediction module 208, a prerender module 210, a client navigation history 212, and an aggregate navigation history 214. Although a number of discrete modules (e.g., 206, 208, 210, 212 and 214) are identified in connection with FIG. 2, the functionality of these modules can overlap and/or exist in a fewer or greater number of modules than what is shown, with such modules residing at one or more processing devices, which may be geographically dispersed. The browser 206 provides for the display of network content, such as a web page 216, a set of search results, or any other type of network data, to a user of the client device by sending and receiving data across a computer network. The web page 216 may be received in response to a network request, such as a Hypertext Transfer Protocol (HTTP) GET request. The web page 216 may be provided in a markup language, such as Hypertext Markup Language (HTML). The web page 216 may also include various scripts, data, forms, and the like, including interactive and executable content such as ADOBE FLASH content, JAVASCRIPT content, and the like.
The browser 206 may further comprise a prerendered web page 218. The prerendered web page 218 represents a web page that was requested and accessed by the prerender module 210 in response to a predicted navigation event provided by the navigation prediction module 208. In the event the user inputs a navigation event as predicted by the prediction module 208, the browser 206 may swap the prerendered web page 218 with the web page 216, thus providing the content associated with the navigation event without the need to send another network request. In some aspects, the swap may occur before the prerendered web page 218 has finished loading. In such cases, the partially loaded prerendered web page 218 may be swapped in to continue loading as the active page.
The memory 202 may further comprise a prerender module 210 to perform fetching of a next web page as identified by the navigation prediction module 208. The prerender module 210 sends a network request for the web page identified to be the likely next navigation destination that the user will select. The web page received in response to this request is then stored in the browser 206 as the prerendered web page 218. In some aspects, the web page request generated by the prerender module 210 is identical to a standard web page request. In some aspects, the web page request generated by the prerender module 210 comprises certain features to facilitate the prerender process.
The memory 202 may also store a client navigation history 212 and an aggregate navigation history 214. The client navigation history 212 comprises a set of navigation events associated with past activity of the browser 206. The client navigation history 212 may track a set of visited URLs, also known as a “clickstream,” which tracks an order in which the user typically visits URLs (e.g., when the user visits a news website, they tend to next select a URL corresponding to the top story of the day), a set of access times associated with the URLs, and the like. In some aspects, the client navigation history 212 comprises a set of URLs and a frequency with which the user has visited each URL. In some aspects, the client navigation history comprises a set of URL pairs, representing a source URL and a destination URL. The aggregate navigation history 214 may comprise similar data as the client navigation history 212, but keyed to multiple users rather than a single user. As with the client navigation history 212, the aggregate navigation history 214 may be stored as a set of URLs and a frequency for each, or a set of URL pairs representing a transition from a source URL to a destination URL.
The client navigation history 212 and aggregate navigation history 214 may represent data collected using one or more browser add-ons, scripts, or toolbars. In some aspects, the client navigation history 212 and/or aggregate navigation history 214 are maintained on a remote server, such as the server 104, and provided to the computing device 200. The computing device 200 may maintain separate records to facilitate the predicting of a next likely navigation event, or it may act in concert with remotely stored data. In some aspects, only aggregate navigation history 214 pertaining to the particular web page the user is currently viewing is provided to the computing device 200 (see FIGS. 6 and 8).
As described above, the aggregate navigation history data 214 can be maintained in an anonymous fashion, with privacy protections for the individual client data that comprises the aggregate navigation history, including, for example, anonymization of personally identifiable information, aggregation of data, filtering of sensitive information, encryption, hashing or filtering of sensitive information to remove personal attributes, time limitations on storage of information, and/or limitations on data use or sharing. The aggregate navigation history 214 data can be anonymized and aggregated such that individual client data is not revealed.
FIG. 3 is a flow diagram depicting an example method 300 for prerendering a web page based upon a predicted navigation event in accordance with aspects of the disclosure. Aspects of the method 300 operate to identify one or more likely navigation destinations from a set of navigation indicators, and then prerender the identified navigation destinations. The method 300 may be performed by a computing device, such as the computing device 200, to eliminate delays in the user web browsing experience by prerendering web pages that are identified as likely navigation targets by the user. For example, the method 300 may be performed by elements of the browser 206, the navigation prediction module 208, and the prerender module 210 acting together. While aspects of the method 300 are described with respect to the computing device 200, the method 300 may also be performed by the server 104, or any device with hardware and/or software designed to accept instructions.
At stage 302, the computing device 200 receives one or more indicators of navigational intent. Navigational intent may be any action that would tend to indicate that the user will generate a particular network request, such as a request for a particular web page. For example, the indicators may provide metrics by which to determine what the particular request will be, such as a confidence value. For example, the user may navigate to a certain web page, from which they generally navigate to another certain web page based upon their browsing history, or the user may move his mouse cursor towards a particular hyperlink embedded within a web page. In some aspects, the indicator is received from a remote server, such as a search engine that embeds an indicator within search results, indicating that most users that submit a particular search query select a particular search result.
At stage 304, after receiving the indicator of navigational intent, the computing device 200 attempts to predict the most likely navigation event. In short, the computing device 200 makes a best guess of to where the user is likely to navigate next, based upon the indicator. Methods of performing this prediction are described below (see FIGS. 4-11).
At stage 306, the computing device 200 prerenders the content from the predicted next navigation event as determined at stage 304. The prerendering process may include storing a prerendered web page within a browser, such as the prerendered web page 218. The computing device 200 may prerender a single web page predicted as the most likely navigation event, or the computing device 200 may prerender multiple pages. In some aspects, the computing device 200 determines the number of pages to prerender based upon one or more system capabilities of the computing device 200, such as available system resources, available network bandwidth, processor speed, installed memory, and the like. In some aspects, the number of pages to prerender may be configurable in one or more user settings. After prerendering the content associated with the navigation event(s), the method 300 ends.
Multiple methods for predicting a next navigation event are provided below. While each method is described separately, it should be appreciated that aspects of the methods may be combined to improve navigation prediction operations.
FIG. 4 is a flow diagram depicting an example method 400 for predicting a navigation event based on a client navigation history in accordance with aspects of the disclosure. The method 400 provides for storing a navigation history for a user, and predicting a next navigation event based upon a navigation history of a particular user. As above, the method 400 may be performed by a computing device such as the computing device 200. In particular, the method 400 may be performed by a navigation prediction module executing on a processor, such as the navigation prediction module 208.
At stage 402, the computing device 200 tracks a user navigation history. For example, the computing device 200 may store records of web pages visited by the user, such as the browsing history commonly maintained in web browsers. The browsing history may comprise the URLs of the web pages visited by the user, the order in which the URLs were visited, and the manner in which the user selected the URL (e.g., whether the URL was a clicked hyperlink, typed into an address bar, a redirect operation from another web page, etc.).
At stage 404, the computing device 200 determines a most likely navigation event or events based upon the user navigation history. The most likely navigation events may be determined by identifying the globally most visited pages for the user, or the navigation events may be associated with one or more current criteria. For example, the computing device 200 may examine the user's navigation history to determine that, when the user is viewing a particular news web page, they almost always select a link to the top news story on that page, or that when the user first opens the browser in the morning, they are likely to navigate to their bank account page to check their daily balance. The computing device 200 may employ various rules, heuristics, and filters to determine the most likely navigation event from the user history. The computing device 200 may associate each navigation event with a particular confidence value, indicating the likelihood that the user will select each navigation event. These confidence values may then be used to sort the navigation events to determine the most likely navigation event. A method to determine a confidence value for a given navigation event is described further below (see FIG. 5).
At stage 406, the computing device 200 reports the most likely navigation event as the predicted navigation event. For example, these predicted most likely navigation event may then be employed by the method described above (see FIG. 3) to facilitate prerendering of the web pages associated with the most likely navigation event.
FIG. 5 is a flow diagram depicting an example method 500 for computing a confidence value for a URL using a user navigation history in accordance with aspects of the disclosure. The method 500 is operable to track navigation events input by the user and to maintain a frequency value for each stored event. The method 500 may be employed to build a client navigation history as used by the method 400, and stored on the computing device 200 as the client navigation history 212.
At stage 502, the computing device 200 tracks the selection of a particular URL. For example, the user may type a URL for a news site into the browser, or click a link on a page. The computing device 200 may monitor the navigation events using functionality built into the browser 206, through a browser extension such as a plug-in or toolbar, or via a third party application executing in tandem with the browser.
At stage 504, the computing device 200 increments a frequency value associated with the URL selected at stage 502. For example, the computing device 200 may track a frequency value associated with each URL selected by a user. The frequency value is a data metric used to rank a number of visits to a particular web site or the number of times a particular navigation event is selected. In response to a selection operation, the computing device 200 may increment the frequency value associated with the URL, for example by 1.0, 5.0, 10.0, 0.5, or any other value. The frequency value associated with the URL represents how often the user has selected the particular URL, and thus is an indicator of how likely the user is to select the URL in the future.
At stage 506, the computing device 200 time decays the stored frequency values for the URLs after a given “sweep interval”. Decaying the URL frequency values in this manner allows for current browsing habits to be more heavily weighted than previous browsing habits. As an example, the computing device 200 may execute the sweep every 30 seconds, every minute, or every 5 minutes during which the user has selected at least one URL. The sweep interval may be conducted in response to the selection of at least one URL during a particular sweep interval to ensure that the navigation history values are not decayed below a threshold value during periods where the user is inactive. The sweep may decay the stored frequency value associated with the URL by a particular value, such as 0.99, 0.5, or 1.0, or by a percentage value, such as 5%, 10%, or 50%. Once the value associated with the URL drops below a given threshold, for example, 0.3, 1.0, or 5.0, the URL may be removed from the list of possible navigation destinations to avoid the list growing too large. After conducting the decay process, the frequency values for the URLs may be persisted to a local storage on the computing device 200, or sent to a remote storage such as provided by the server 104.
At stage 508, the stored frequency values may be used to determine the relative frequency with which the user visits particular web sites. The frequency value thus provides a basis from which a confidence value associated with a navigation event leading to each web site may be derived. In some aspects, the frequency value itself may be provided as the confidence value. In some aspects, the confidence value is determined by comparing a frequency value for a particular web page with the entire user navigation history. For example, the navigation event with the higher frequency value may be associated with a particular percentage confidence value, the second highest frequency value a lower percentage, and the like. In some aspects, the confidence value is determined by frequency value by the total number of logged navigation events. For example, the frequency value of a particular URL may be divided by the sum of all frequency values to determine a confidence value.
For example, a user may be in the process of buying a home, and thus regularly checking financial and banking websites for mortgage rates. During this time, these financial and banking sites would have high values and thus be more likely to be prerendered, thus improving the user experience while searching for a mortgage rate. After completing the home purchase process, the user is likely to lose interest in day to day rate fluctuations, and thus it is no longer optimal to prerender these websites, since the user is unlikely to visit them. As such, providing for a time decay value allows these sites to fall off of the list over time.
FIG. 6 is a flow diagram depicting an example method 600 for predicting a navigation event based on an aggregate navigation history in accordance with aspects of the disclosure. The method 600 is operable to track navigation events voluntarily submitted by users to determine likely navigation patterns. The navigation patterns are then analyzed, such as by a server 104, and supplied to the user to facilitate navigation event prediction during the browsing process. For example, a server, such as the server 104, may send updates to a computing device, such as the computing device 200, as the user browses to different pages, to provide information on which link displayed on a given page is most likely to be selected based on the aggregate navigation history.
At stage 602, the server 104 receives a set of navigation information comprising a browsing history. The browsing history is preferably provided by using an “opt-in/out” method, where the user specifically enables (or disables) reporting functionality to provide elements of their browsing history to the server 104. In addition, personally identifying data can be anonymized and aggregated before it is stored or used, such that no personal information is stored or accessible. A browsing history may be tracked and provided to the server 104 via a browser plug-in or toolbar installed on the user's computing device which tracks the user's browsing history, or by the web browser itself. The browsing history may be combined with other received browsing histories to create a set of aggregate data used in a similar manner as the client navigation history described with respect to FIG. 4, to predict a likely navigation event. The received navigation history may be anonymized to remove any personally identifying information. In some aspects, the received navigation history is received with individual URLs and/or transitional URL pairs provided in a hashed data format to remove any personally identifying information prior to transmission to the server 104.
At stage 604, the server 104 determines a confidence value for each URL on a particular web page, based on the navigation information received at stage 602. For example, the server may employ a method similar to that disclosed above with respect to FIG. 5 for generating confidence values for URLs on a page, except the navigation events are determined based upon aggregated data instead of specific user data. As above, the server 104 may compute confidence values based upon the frequency values derived from the navigation information. In some aspects, confidence values are determined by the percentage of the time that users selected a particular navigation event when they were presented with the choice to select the particular navigation event. The transitional URL pairs provide for the determination of a confidence value by dividing a frequency value of a source/destination URL pair by a total number of appearances of the source URL. In some aspects, the server may determine navigation events based upon transitions from a first page to a second page, rather than from a pure visit frequency metric. The server 104 may maintain an index of web pages and associated URLs and confidence values for each link on the web page, such as in a database. For example, a news site may have five URLs pointing to different news stories. The server 104 may receive aggregate data indicating that one of the five news stories is selected 60% of the time, with the other four being selected 10% of the time each. As such, the server 104 would index the page in a database with a 60% likelihood for the first story link, and 10% likelihoods for each of the other four story links.
In some aspects, the server 104 maintains history data in a confidential manner, such as by converting each URL to a hash value at stage 606. In this manner, the server 104 may provide predicted URL data to a client device without disclosing any personal user data. For example, a user may visit a banking web page that has a particular user name and password login. Depending upon the user, the banking web page may provide URLs to each account the user possesses. Each user accessing the page may have a different set of links provided, depending upon the accounts the user has with the bank. By converting the links on the page to non-reversible hash values, the server 104 may provide confidence values that are not associable to links on the page unless the user also possesses access to the same links (e.g., the client can apply the hash function to links they already possess on the currently viewed page to determine if the confidence values apply). As described above, in some aspects, the hash value is computed by the computing device 200 prior to sending navigation history data to the server 104. In this manner, the server 104 may receive the navigation history data in the hashed format, without the need to compute a hash value.
At stage 608, the server 104 transmits the hash values and confidence values associated with the hash values to a client device, such as the computing device 200. The transmittal may be in response to a request from the computing device 200 for a particular URL. In some aspects, the server 104 may transmit the hash values and confidence values in response to a request for such values from a service executing on the client device 200. For example, when the computing device 200 requests the news web page described above, the server 104 provides the hash values and confidence values for the five story links present on that page. The computing device 200 may also request data for particular link hash values by first generating a hash value on the client side, then requesting a confidence value for the particular hash value from the server 104.
FIG. 7 is a flow diagram depicting an example method 700 for computing a confidence value for navigation events associated with a URL using an aggregate navigation history in accordance with aspects of the disclosure. The method 700 serves to compare navigation events from a given URL received from a plurality of users, in order to determine how likely each individual navigation event is. The confidence values may be determined in relation to a particular “source” web page, with different confidence values for each URL depending upon the page the user is currently viewing. For example, the confidence values may be used above as described with respect to stage 604 of the method 600 (see FIG. 6).
At stage 702, the server 104 examines received browsing histories and computes a number of instances for each navigation event as associated with a particular URL. As described above, the instance value may be a percentage or a raw number.
At stage 704, the server 104 may determine if the number of visits to the URL exceeds a minimum threshold of statistical significance. For example, five visits to a particular URL may not provide statistically significant data sufficient to reasonably predict a likely navigation event away from the URL. For example, if the number of instances of the event is less than 1000, the server 104 may proceed to stage 710, and not calculate a probability for the event because the sample size is insufficient.
At stage 706, the server 104 may determine if a minimum number of users have submitted data regarding the URL to provide statistically significant data. For example, the method 700 may require that at least 50 users have provided data in order to compute and store a confidence value for the navigation event. Otherwise the method 700 may proceed to stage 710 and disregard the event until a sufficient number of users have provided data. As above, the threshold value may fluctuate depending upon the size of the dataset.
At stage 708, the server 104 determines a window size of recent instances. The window size refers to the number of latest visits to the URL that will be examined to determine the confidence value, or a length of time to search back through the instances. The window size may be determined based on the amount of traffic the URL receives, how often the content of the URL changes. For example, a news website that has constantly changing content might require a small instance window, because links from the regularly changing URL would grow stale. A website with a small amount of traffic would typically require a longer window size in order to gather enough results for statistical significance. The window size might be set at 50 instances, 100 instances, 1000 instances, all instances within the last hour, within the last day, within the last week, or the like.
At stage 712, the server 104 computes the number of times each particular navigation event, such as the next URL visited for the current URL, occurs within the instances defined by the window size determined at stage 710. For example, out of 1000 visits to a news website, a particular article might be selected 600 times, resulting in a confidence value of 60% for navigating to that article from the URL. While the present example primarily relates to determination of a navigation event based upon a number of accesses as a percentage of total navigation events, additional heuristics may also be used to derive the likely event based upon information supplied by the user, such as the previous navigation event (e.g., the website that led to the currently analyzed URL), the time of day (e.g., users are more likely to check news sites when in the morning when they arrive at work), the user's location (e.g., users in a particular geographic region are likely to check sports scores for local teams), or other demographic information.
At stage 714, the server 104 optionally compares the confidence values for the navigations events from the URL with a threshold value. If the confidence values do not meet the threshold value, the server 104 may identify a subset of available navigation events, as possible predicted likely navigation events. In this manner the server 104 avoids predicting navigation events when the event does not have a statistically significant likelihood of occurring, thus potentially saving bandwidth on prerender operations on pages that are unlikely to be visited. The threshold may be set at a variety of different values, such as 5%, 25%, 50%, or 75%. In some aspects, the threshold may be dynamically altered based upon the number of navigation links present at the URL, the type of URL, the traffic of the URL, the speed at which content changes at the URL, and the like. If the confidence values do not meet the minimum threshold, the server 104 may filter out the possible events that do not meet the minimum threshold.
If the navigation event or events meet the minimum threshold, or the method 700 does not check for a minimum threshold, the most likely navigation event or events and the likelihood for each event are stored along with the URL at stage 716. The navigation events and confidence values may be supplied in response to a request to the user, such as occurs at stage 608 described with respect to FIG. 6. The method 700 ends after computing and storing the confidence values for the navigation events associated with the URL.
FIG. 8A is a flow diagram depicting an example method 800 for predicting a navigation event based on an aggregate navigation history using hash values to anonymously manage link data in accordance with aspects of the disclosure. The method 800 provides logic by which a computing device 200 may predict a navigation event based upon data received from a server 104, such as the data generated by the method 700 described with respect to FIG. 7.
At stage 802, the computing device 200 receives a set of data from a remote server 104, the set of data comprising information associated with an aggregate browsing history of a web page. This aggregate data may be received in response to a request made by the computing device 200 in response to navigating to a particular web page. The aggregate data may represent a collection of data received by a remote server from a plurality of users. For example, a web browser plug-in may allow the user to “opt-in/out” of functionality that may send their anonymized navigation history to a remote server. The remote server may then collect navigation histories from a plurality of users, stored as an aggregate navigation history, such as described above (see FIG. 7). For example, the navigation prediction module 208 may generate a request to the server 104 every time the user navigates to a web page, for the aggregate browsing data associated with that web page. The navigation prediction module 208 may then predict a likely next navigation event using the received data, so as to supply the prerender module with a next page to prerender to improve the browsing experience.
Due to the data's aggregate nature, it can be provided as a series of hash values to protect individual user information, as described above with respect to FIG. 6. As such, the computing device 200 associates the received hash values and confidence values with the links present on the current URL. To begin this process, at stage 804, the computing device computes a hash value for each link on the current page using the same hash function as used by the server 104 to anonymize the link data. As described above, in some aspects the hash value is computed on the computing device prior to sending navigation history data to the server. In such cases, the hash value would match the original computed value determined by the computing device prior to the navigation event being transmitted to the server, rather than a value computed on the server.
At stage 806, the computing device 200 compares the computed hash values with the received hash values from the server 104. In this manner, the computing device 200 may match the confidence values and hash values received from the server 104 with the links available for the user to select on the currently viewed web page. The confidence values indicate a likelihood that a particular navigation event associated with the hash value will be selected. The computing device 200 may thus map the currently viewable links with the received confidence values.
At stage 808, the computing device 200 identifies the link or links with the highest confidence value or values as the predicted next navigation event. The method 800 ends after predicting the next navigation event.
FIG. 8B is an illustration of an example interface 810 of a web browser employing an example method for predicting a user navigation event based on a navigation history in accordance with aspects of the disclosure. The illustration depicts a web browser interface 810 displaying a web site and a set of navigation history data 812. The web page 810 comprises one or more links 814, 816, 818, 820. These links 814, 816, 818, 820 may be URLs that, when selected by a user, direct the web browser to display a set of content associated with the selected link.
The navigation history data 812 comprises data associated with the links 814, 816, 818, and two other links, Link E and Link F that are not present for the current user viewing the page. The navigation history data 812 may represent an analysis of the individual user's navigation history (See FIGS. 4-5, 9-11), or an aggregate navigation history (See FIGS. 6-11). The navigation history 812 comprises information about the links 814, 816, 818, and a confidence value associated with each link.
The navigation history 812 may be used by other aspects of a computing device 200, such as the navigation prediction module 208, to predict the next navigation event. For example, in the present illustration, according to the navigation history 812, there is a 30% chance the user will select Link A 814, a 60% chance the user will select Link B 816, and a 5% chance the user will select Link C 818. Link D 820 does not have any associated data stored in the navigation history 812. The lack of data for Link D 820 may be explained in a variety of manners, such as that the chance of selection of Link D 820 is below a threshold value, or that no data has been submitted for Link D 820. The navigation history 812 also displays a non-zero chance of selecting two links that are not present, Link E and Link F. These links may have been removed from the web page in an update, or they may not be visible to all users, such as the user currently accessing the page. In accordance with aspects of the disclosure, the navigation prediction module 208 identifies Link B 814 as a predicted next navigation event because the confidence value of Link B 814 is greater than the values for Link A 812 and Link C 818.
FIG. 9 illustrates an example of directed graph for storing navigation events. This graph shows one possible implementation of the client navigation history 212 as described above (see FIG. 2). The graph depicted in FIG. 9 provides a reference to each navigation event (e.g., a website URL) as a vertex in the graph, with the edges weighted by the number of visits to a destination navigation event from a source address. As new navigation events occur, vertices are added to the graph, edge weights are updated, and new edges are generated.
The directed graph may be associated with a particular user, a particular group or subset of users, all users in aggregate, or any other division as appropriate for predicting future navigation events. The directed graph may be stored locally or remotely, as described above with respect to client navigation histories and aggregate navigation histories (see FIGS. 2, 4-8A). As described above, navigation histories maintained remotely may be maintained in an opt-in manner, requiring users to explicitly allow their navigation history to be stored for use in prediction of navigation events. Data maintained in this manner may be anonymized and depersonalized in order to protect user privacy.
Although the depicted example graph shows relationships between pairs of navigation addresses, higher order graphs may be constructed from a map where the key is the last “n” visited navigation events and the value is an array of pairs of destination addresses and counts. For example, a first order model might depict a single address pair transition (e.g., address A→address B) to predict the first destination, while a second order model might by keyed using a pair of source addresses, and predict a third address as a destination (e.g., when the user starts at address A, and then navigates to address B, what is the likely next event?). Higher order models are also possible, with increasingly lengthy navigation histories being examined to determine the likely navigation event. In the present example, the directed graph depicted in FIG. 9 is associated with a two part navigation history (e.g., “n” is equal to two), where the site previously viewed is “URL F,” and the current site is the source vertex in the graph (e.g., URL A, B, C, D, or E).
Examination of longer navigation histories (e.g., higher numbers of “n” previous events examined) may be more probative of user behavior, due to the ability to more closely match past observations to current conditions. As such, navigation prediction operations may be weighted by the length of the history examined. Prediction operations may also require a minimum number of occurrences, or they may be weighted by the number of occurrences in order to prevent a long navigation history with a single instance from overriding a shorter history with an overwhelming data count.
Prediction operations may also be performed using a subset of the recent navigation history. For example, a set of previously viewed pages A, B, and C may be indicative of a certain navigation pattern (e.g., after the user visits A, B, and C in any particular order, the user then tends to visit site D). Thus, a user visiting sites A, E, F, C, G, B (in that order) may use the information associated with the “loose” set of previously viewed pages A, B, and C because each of A, B, and C are present within the most recent navigation history, allowing for additional sites to be accessed in between, or modifications in the navigation order. An example of a method for predicting a likely navigation event using a directed graph is described below (see FIG. 11).
FIG. 10 is an illustration of an example of a method 1000 for building a directed graph in accordance with aspects of the disclosure. As navigation events occur, they are added to the directed graph for use in navigation prediction operations. Connections between vertices of the graph (e.g., website addresses) are weighted by the number of times the browser navigates from the source vertex (e.g., the source website address) to the destination vertex (e.g., the destination website address).
At stage 1002, a navigation event is received. For example, a link may be selected from a website, e-mail, or instant message client, a URL may be typed into an address bar, or another application may initiate a navigation operation (e.g., a selection of a search result provided by a separate search application).
At stage 1004, a determination is made as to whether the received navigation event corresponds to an entry within a graph. As described above with respect to FIG. 9, the navigation event used as the key to identify a graph may be a plurality of vertices representing a recent navigation history, rather than a single navigation event.
If the navigation event is not present within the directed graph, a new vertex for the navigation event is added at stage 1006. Otherwise, the method proceeds to stage 1008.
At stage 1008, the counter value defining the weight of an edge of the graph between the current or source URL and the destination URL is incremented. In a directed graph with greater depth than a single navigation event, an edge from the source “n” navigation events to the destination navigation event may be incremented. In this manner, navigation events between vertices of the graph are stored in the weights of the edges of the directed graph.
FIG. 11 is an illustration of an example of a method 1100 for predicting a navigation event using a directed graph in accordance with aspects of the disclosure. Once created, the directed graph may be used to predict future navigation events based on a past navigation history.
At stage 1102, the past “n” navigation events in a navigation history are determined. For example, the most recent web pages visited by the user may be identified, in the particular order in which the user visited them. A navigation event history may be identified for a particular web browser tab or instance, or across all active browser tabs or instances.
At stage 1104, the navigation event history determined at stage 1102 is mapped to a navigation history data graph. The navigation event history may be mapped to multiple data graphs, depending upon the length of the history and the “n” order depth of the graphs. For example, a navigation history of URL A→URL B→URL C→URL D may map to up to four separate directed graphs, a graph for URL D, a graph for URL C→URL D, a graph for URL B→URL C→URL D, and a graph for URL A→URL B→URL C→URL D.
At stage 1106, a confidence value is determined for the potential destination addresses within the directed graphs determined at stage 1104. The potential destination addresses associated with each directed graph may also be compared against the set of addresses present on a current web page. For example, confidence values may not be identified for links that are not active and selectable on the web page the user is viewing.
The confidence value may be determined using the weights of the edges between the source vertex of the directed graph (e.g., the currently viewed page) and each destination vertex linked to the source vertex. The confidence value may be the probability of each navigation event (e.g., the count weight of the possible navigation event divided by the total count of potential next navigation events), weighted such that higher-n entries are given more weight.
Deeper graphs tend to provide more specific data, but graphs with more data points are better because they are more representative. As such, it may be appropriate to use a formula to determine a weight for each probability given the tradeoffs between different probability calculations. For example, if a data set has 5 graphs of depths 1 through 5, a probability value from each graph might be weighted using the graph depth and the number of samples in the graph. One possible formula for determining the weight of each probability value may be:

weight=graph_depthN*samples_in_graph  (Eq. 1)

Graph_depth is the number of navigation events used as the key to the graph, samples_in_graph is the number of navigation events stored in the graph, and N is a number greater than 1 used to configure the bias towards graph depth instead of sample size. This formula may determine the weight or significance of each graph, and the probabilities for each URL from each graph may be determined according to that weight.
At stage 1108, one or more likely navigation events are identified using the confidence values determined at stage 1106. For example, all events with a confidence value greater than a threshold value may be identified as likely navigation events (e.g., all navigation events with at least a 50% confidence value, at least a 75% confidence value, or at least a 90% confidence value), a certain number of events with top confidence values may be identified as likely navigation events, or a top navigation event from each examined directed graph may be identified as a likely navigation event.
At stage 1110, one or more likely navigation events are prerendered. Although the present example describes the use of likely navigation events for prerendering, other actions may also be taken to assist the user with accessing the content associated with the likely navigation event. For example, the likely navigation events may be presented to the user in a separate interface window for selection, or various prefetching processes may be enabled based upon the probability of each navigation event. In some aspects, increasingly aggressive processes are performed in response to the probability of selection of the navigation event. For example, a given navigation event may be prerendered at greater than 90% probability, but only domain name services (DNS) information precached at 60% probability, and no action taken at all at below 10% probability.
The stages of the illustrated methods described above are not intended to be limiting. The functionality of the methods may exist in a fewer or greater number of stages than what is shown and, even with the depicted methods, the particular order of events may be different from what is shown in the figures.
The systems and methods described above advantageously provide for an improved browsing experience. By predicting the next navigation event, the browser can perform prerender operations to minimize the amount of time users wait for web pages to load. Multiple methods to perform the prerender operations provide a flexible and robust system for determining the next navigation event.
As these and other variations and combinations of the features discussed above can be utilized without departing from the disclosure as defined by the claims, the foregoing description of the embodiments should be taken by way of illustration rather than by way of limitation of the disclosure as defined by the claims. It will also be understood that the provision of examples of the disclosure (as well as clauses phrased as “such as,” “e.g.”, “including” and the like) should not be interpreted as limiting the disclosure to the specific examples; rather, the examples are intended to illustrate only some of many possible embodiments.

## Claims

1. A computer-implemented method for predicting a user navigation event, comprising:
generating, using a processor, a mapping between a directed graph and a navigation history, the navigation history comprising one or more previous navigation events associated with a browser, an edge of the directed graph being weighted by a count value representing a number of times a navigation event has occurred from a source vertex to a destination vertex coupled to the edge;
identifying a confidence value for one or more given navigation events using the directed graph, the confidence value representing a probability of a likely navigation event; and
prerendering at least one of the one or more given navigation events as the likely navigation event based on the confidence value, wherein the confidence value of the likely navigation event exceeds a threshold value.

2. The method of claim 1, wherein the directed graph is keyed to at least one of the one or more previous navigation event in the navigation history.

3. The method of claim 2, wherein the at least one previous navigation event is identified in an order each of the at least one previous navigation events were visited.

4. The method of claim 1, further comprising:
identifying selected ones of the one or more previous navigation events in the navigation history; and
determining which of the selected ones of the one or more previous navigation events is keyed the directed graph.

5. The method of claim 1, wherein the confidence value is weighted by a depth of the directed graph.

6. The method of claim 5, wherein a weight of the directed graph is determined by a formula graph_depthN*samples_in_graph, wherein graph_depth is the depth, samples_in_graph is a number of navigation events associated with the directed graph, and N is a numerical value used to adjust the significance of the graph_depth term in the weight calculation.

7. The method of claim 1, wherein the browser is a web browser.

8. A non-transitory computer-readable storage medium comprising instructions that, when executed by a processor, cause the processor to perform a method, the method comprising:
generating a mapping between a directed graph and a navigation history, the navigation history comprising one or more previous navigation events associated with a browser, an edge of the directed graph being weighted by a count value representing a number of times a navigation event has occurred from a source vertex to a destination vertex coupled to the edge;
identifying a confidence value for one or more given navigation events using the directed graph, the confidence value representing a probability of a likely navigation event; and
prerendering at least one of the one or more given navigation events as the likely navigation event based on the confidence value, wherein the confidence value of the likely navigation event exceeds a threshold value.

9. The non-transitory computer-readable storage medium of claim 8, wherein the directed graph is keyed to at least one of the one or more previous navigation event in the navigation history.

10. The non-transitory computer-readable storage medium of claim 9, wherein the at least one previous navigation event is identified in an order each of the at least one previous navigation events were visited.

11. The non-transitory computer-readable storage medium of claim 8, wherein the method further comprising:
identifying selected ones of the one or more previous navigation events in the navigation history; and
determining which of the selected ones of the one or more previous navigation events is keyed the directed graph.

12. The non-transitory computer-readable storage medium of claim 8, wherein the confidence value is weighted by a depth of the directed graph.

13. The non-transitory computer-readable storage medium of claim 12, wherein a weight of the directed graph is determined by a formula graph_depthN*samples_in_graph, wherein graph_depth is the depth, samples_in_graph is a number of navigation events associated with the directed graph, and N is a numerical value used to adjust the significance of the graph_depth term in the weight calculation.

14. A system for predicting a user navigation event, comprising:
a memory; and
one or more processors coupled to the memory, the one or more processors being configured to:
generate a mapping between a directed graph and a navigation history, the navigation history comprising one or more previous navigation events associated with a browser, an edge of the directed graph being weighted by a count value representing a number of times a navigation event has occurred from a source vertex to a destination vertex coupled to the edge;
identify a confidence value for one or more given navigation events using the directed graph, the confidence value representing a probability of a likely navigation event; and
prerender at least one of the one or more given navigation events as the likely navigation event based on the confidence value, wherein the confidence value of the likely navigation event exceeds a threshold value.

15. The system of claim 14, wherein the directed graph is keyed to at least one of the one or more previous navigation event in the navigation history.

16. The system of claim 15, wherein the at least one previous navigation event is identified in an order each of the at least one previous navigation events were visited.

17. The system of claim 14, wherein the one or more processors are further configured to:
identify selected ones of the one or more previous navigation events in the navigation history; and
determine which of the selected ones of the one or more previous navigation events is keyed the directed graph.

18. The system of claim 14, wherein the confidence value is weighted by a depth of the directed graph.

19. The system of claim 18, wherein a weight of the directed graph is determined by a formula graph_depthN*samples_in_graph, wherein graph_depth is the depth, samples_in_graph is a number of navigation events associated with the directed graph, and N is a numerical value used to adjust the significance of the graph_depth term in the weight calculation.

20. The system of claim 14, wherein the browser is a web browser.