Patent Publication Number: US-2012036216-A1

Title: Profiling method and system

Description:
FIELD OF THE INVENTION 
     The invention relates generally to profiling of recipients, and more particularly, to a method for profiling recipients on the basis of responses given by the recipients to questions delivered to the recipients. 
     BACKGROUND 
     Conventional methods for delivering advertisement data typically involve broadcasting messages to mass markets. This is usually described as a “Spray and Pray” approach, wherein the advertisement data is delivered to a wide audience and it is hoped that the advertisement data will be received by a sufficient number of potential recipients that are appropriate targets of the advertisement. Although an advertiser may take steps to ensure that the advertisement data is delivered via channels that traditionally are expected to reach a significant concentration of potential recipients, there is nevertheless little or no means to guarantee that the advertisement data is delivered to most appropriate recipients. An example of conventional mass marketing strategy is delivery of advertisement data through television channels and inclusion of the advertising data into commonly visited Internet websites. 
     Direct mailing campaigns via traditional mail and via electronic mail are considered to be more accurate in delivering advertisement information to targeted individuals and/or groups. In addition to the conventional electronic mail it is possible to use other electronic message delivery means for delivery of advertisement data, for example SMS-messages (Short Message Service) or MMS-messages (Multi Media Service) that can be delivered via a mobile communication network. Sending advertisement messages to recipients via a mobile communication network in a large scale causes often a lot of situations in which a certain advertisement message is received by an individual that is far from an optimal target for that advertisement message. For example, a message advertising large cars such as suburban vehicles (SUV) may be received by an environmentally conscious person that has adopted an attitude of hostility to such cars. In order to avoid situations of the kind described above or at least to minimise the amount of such situations there is a need to profile the recipients in such a manner that advertisement messages can be targeted to suitable recipients. 
     The profiling or characterisation of the recipients can be based on answers given by the recipients to questions that have been delivered to the recipients e.g. via a communication network. Furthermore, the profiling can be based on demographic data related to the recipients. The answers to the questions and possibly also the demographic data constitutes raw data with the aid of which the recipients are categorised. In a situation in which there is only one question or only a few questions, the profiling may be too coarse or, in some cases, even misleading. For example, a question may be “Do you think the environment is important: Yes/No?”. Most of the people would answer “Yes” to this question albeit their actions and/or attitudes do not support that because the answer “No” would indicate exceptional egomania. From the advertisement point of view this “Yes” answer would lead to addressing ecologically friendly products to such recipients who would actually, for example, drive a SUV with a large consumption of gas and/or practise other behaviour that is far from environmental. In a situation in which there are a large number of questions, the number of different answer combinations gets high. For example, if there are N questions each of which having M answer-alternatives, the number of different answer combinations is M N . From the viewpoint of practical needs, the number of different recipient categories into which the recipients will be profiled has to be substantially smaller than the number of different answer combinations (M N ). Therefore, the different answer combinations have to be mapped to a lower number of recipient categories in a manner that provides a sufficiently veracious profiling of the recipients. 
     SUMMARY 
     The invention is embodied by a system for characterising a respondent according to at least one predetermined characteristic of the respondent and including a profiling network, the profiling network comprising a plurality of nodes connected by links, including one or more category nodes associated with said characteristic and question nodes associated with questions delivered to the respondent, and one of the links emanating from a first node and connecting to a second node, the first and second node being part of said plurality of nodes, wherein the system is arranged to evaluate a node value for the second node in dependence on a node value of the first node and/or on a link value of the link connecting the first node to the second node and indicative of a relationship between the first node and the second node. 
     The characterisation of a respondent is based at least partly on link values that are defined according to pre-determined rules for questions delivered to the recipients and for the recipient categories. The number of question nodes can be larger than the number of category nodes in the profiling network. This larger number of question nodes is connected to the smaller number of category nodes through links between the nodes. Hence, the profiling network allows a high number of different answer combinations provided by the recipients of the questions to be mapped to a lower number of categories that provides a sufficiently veracious profiling of the recipients. 
     The profiling network can be easily changed by adding or omitting nodes, adding or omitting links or changing link values. Since a link has a directional effect, the phrase “the link connects the first node to the second node” must be understood as the link emanates from the first node and points to the second node. 
     In a special embodiment of the system, the first node is one of the category nodes and the second node is a different one of the category nodes, allowing the node value of one category node to influence the node value of another category node. 
     In special embodiment one of the category nodes is linked to one of the question nodes and said question node is linked to a different one of the category nodes. This stepped link allows the relation between two category nodes to be determined by the recipient&#39;s answer to the question associated with the question node. 
     In another embodiment the link value is indicative of the relative importance of the link compared to different links emanating from the same first node. This allows one node to have different effects on two or more nodes linked to this node. 
     The invention also relates to a method of characterising a respondent, a method of setting up a profiling network, a computer program for characterizing recipients into pre-determined recipient categories, and a computer readable medium. 
     In a further aspect of the invention, the first node is one of the category nodes or one of the question nodes and the second node is one of the category nodes or one of the question nodes. 
     In a special embodiment the first node is a question node and the second node is a category node. The setting of the link between these nodes may be made dependent on the response provided by the respondent on the question associated with the first node. 
     The further aspect also includes a database comprising a storage system arranged to hold a plurality of sets of records, a first set of records corresponding to questions for delivery to potential respondents, and a second set of records corresponding to potential responses to the questions from actual respondents, wherein the database comprises an interface for use in specifying: a first set of links between individual questions of the first set and responses of the second set, each said question being capable of having a link to more than one different response of the second set and the database being operable to further store first link data indicative of a plurality of different links between a given individual question and a corresponding plurality of responses of the second set; and a second set of links between individual questions of the first set, each said question being capable of having a link to one or more other questions, the database being operable to further store second link data indicative of a plurality of different links between the one question and a corresponding plurality of said other questions. 
     The supporting and/or the implementation of the functionality for profiling the recipients are/is achieved by a combination of features recited in each independent claim. Accordingly, dependent claims prescribe further detailed implementations of the present invention. 
     Various exemplifying embodiments of the invention together with additional objects and advantages will be best understood from the following description of exemplifying embodiments when read in connection with the accompanying drawings. 
     The exemplifying embodiments of the invention presented in this document are not to be interpreted to pose limitations to the applicability of the appended claims. The verbs “to comprise” and “to include” are used in this document as an open limitation that does not exclude the existence of also unrecited features. The features recited in depending claims are mutually freely combinable unless otherwise explicitly stated. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The exemplifying embodiments of the invention and their advantages are explained in greater detail below with reference to the accompanying drawings, in which: 
         FIG. 1  shows a high-level flow chart of a method according to an embodiment of the invention for profiling recipients; 
         FIG. 2   a  is a schematic diagram showing an example of questions and categories used to profile respondents; 
         FIG. 2   b  is a schematic diagram showing an example of a profiling network comprising links between the questions and categories of  FIG. 2   a;    
         FIG. 2   c  is a schematic diagram showing an alternative profiling network comprising links between the questions and categories of  FIG. 2   a;    
         FIG. 3   a  is a schematic diagram showing a first example of paths traced through the profiling network of  FIG. 2   b;    
         FIG. 3   b  is a schematic diagram showing a second example of paths traced through the profiling network of  FIG. 2   b;    
         FIG. 4  is a schematic diagram showing a distributed system within which embodiments of the invention operate; 
         FIG. 5  is a schematic diagram showing components of the profiling system of  FIG. 4 ; 
         FIG. 6   a  shows a diagram illustrating an exemplifying pre-determined rule according to which links pointing to questions and to recipient categories can be set in a method according to an embodiment of the invention; 
         FIG. 6   b  shows a diagram illustrating exemplifying links that have been set according to the pre-determined rule of  FIG. 2   b  in a method according to an embodiment of the invention; 
         FIG. 7  shows a diagram illustrating exemplifying links that have been set according to a pre-determined rule in a method according to an embodiment of the invention; 
         FIG. 8  shows a diagram illustrating exemplifying links that have been set according to a pre-determined rule in a method according to an embodiment of the invention; and 
         FIG. 9  shows a diagram illustrating exemplifying links that have been set according to one or more pre-determined rules in a method according to an embodiment of the invention. 
     
    
    
     DESCRIPTION OF THE EXEMPLIFYING EMBODIMENTS 
       FIG. 1  shows a high-level flow chart of a method according to an embodiment of the invention for profiling one or more recipients into one or more recipient categories. The recipient categories can be for example: “environmental mindset” and “gender”. The questions can be embodied as messages containing a content item prompting the recipient for a response. An example of a content item can be an advertisement, which can be considered a form of question: e.g. an image showing a florist shop and a suggestion that the recipient might be seeking a job in association with the florist shop; or e.g. an image showing a SUV, suggesting that the recipient might like further information relating to the SUV. In  FIG. 1  these are shown in the form of questions that we paraphrase here as: “Would you like to drive a suburban vehicle? Yes/No”, “Want to be a florist?”, “Bottled water or tap water?”, or “What is your age in years?” etc. The task is to profile the recipient or recipients into one or more of the recipient categories on the basis of the responses given by the recipient or recipients to the questions sent to the recipient or recipients. In this invention questions should be regarded as including explicit questions, such as the above paraphrased questions, and implicit questions that prompt the recipient for a response, such as advertisements. 
     As can be seen from  FIG. 1 , the method can be broadly characterised as comprising a plurality of phases  101 ,  102 ,  103 , each of which can be processed independently of the other and can be triggered part-way through the operation of other phases. Phase  101  comprises receiving and/or defining questions to be used in identifying recipient categories, and indeed receiving and/or defining these categories. Questions and categories can be defined at any time and/or retrieved from a repository holding same. Phase  102  comprises specifying links between the questions and categories so as to create a network of nodes represented by questions and categories, together with specifying link values. A link emanates from a first node and links this first node to a second node; in a network it may connect question to question, question to category, category to question, and/or category to category. Several links may emanate from a node, and links from different nodes may connect to one other node. A link value may include a link ranking and/or a link weighting corresponding to the link. A link ranking is a parameter indicative of the relationship between the first node and the second node in the network, while a link weighting is a parameter indicative of the relative importance of a given link emanating from a given node compared to different links emanating from the same given node. 
     A link from a first node to a second node affects the value of the second node. The effect of a link emanating from a question node may be dependent on the answer the respondent provides to the question associated with the question node. If there are several possible answers to the question, each of these answers may be assigned to a different link, linking the question node to different nodes. A link between the first and second node associated with a particular answer will affect the value of the first node if that answer is provided; it will not affect the value of the first node if that answer is not provided. In the latter case the link is regarded as non-existent when calculating the node values of the network. A link emanating from a category node is usually existent, independent of answers provided. A link emanating from a question node may, in a special case, also be made independent of answers provided. 
     A link from a first node to a second node may affect the value of the second node in several ways. A link ranking of the link may be added to the value of the second node; the link ranking may be weighted before adding it to the value of the second node; the value of the first node may be added to the second node; the value of the first node may be weighted before adding it to the value of the second node. Any combination of the above ways is possible. 
     An example of the output of phase  101  is shown in  FIG. 2   a , where nodes corresponding to categories are depicted differently to nodes corresponding to questions. The output of phase  102 , a profiling network N 1 , is shown in  FIG. 2   b  for the case where only some links have been specified between nodes, and the links that exist have been assigned link rankings but not link weightings. 
     As mentioned briefly above, it is to be noted that questions can be retrieved according to Phase  101  at any time, and indeed the design of the network can be amended according to Phase  102  at any time, either to account for newly added questions and/or to change the link rankings applied to existing questions. Indeed,  FIG. 2   c  shows a different network of links between the nodes, where Q 2  is linked to category C 1  but an answer of No and a link ranking of ⅓, while Q 1  is linked to category C 2  with a link ranking of value 1.0. 
     Phase  103  involves collecting answers to the questions and tracing a path through the network on the basis of the collected answers, so as to assign category values to the respondents. As an alternative to tracing a path on the basis of actual answers, paths can be identified on the basis of a set of hypothetical answers which may, for example, be specified in a log file or similar. Tracing paths through the network N 1  can be visualised as activating links through the network. In Phase  3  a ranking is assigned to question nodes and category nodes. The ranking of a question node is determined by a value assigned to that node. Similarly, the ranking of a category node is determined by a value assigned to that node. Such a node value may be determined by an initial ranking or initial value of the node, any link value of a link pointing to the node, or the node value of the node from which the link is emanating or any combination of these values. 
     An exemplary set of paths is shown in  FIG. 3   a  for answers received from a first respondent in relation to the network shown in  FIG. 2   b : from this example it can be seen that the previously dashed lines have become solid lines, thereby indicating paths through the profiling network N 1  for this respondent, which terminate at the categories C 1 , C 2 . The values of the link rankings for the paths are combined so as to enable calculation of values for each of the categories, and thereby provide a measure of correlation for the respondent to a particular category. For example, in the case of respondent  1 , his correlation with the gender corresponding to C 1  is ⅓, while his correlation with the environmental mindset corresponding to C 2  is ⅓+½=0.833. A second exemplary set of paths is shown in  FIG. 3   b  for answers received from a second respondent, who provided quite different answers to those provided by the first respondent. Accordingly, his correlation with the gender corresponding to C 1  is ⅓+½=0.833, while his correlation with the environmental mindset category C 2  is 0. 
     Whilst the examples shown in  FIGS. 2   a - 3   b  are representative of a profiling network comprising only a few nodes, it will be appreciated that a typical profile updating exercise is likely to involve a network comprising hundreds of nodes and a commensurate number of links there between. In addition, respondents are likely to provide their responses via a range of communications mediums and from a range of devices. Accordingly, and in order to process the data received from such respondents in a scalable manner, the steps involved in Phases  102  and  103  are performed by various components of a distributed computer system such as that shown in  FIG. 4 . In the following description a question node is called question and a category node is called category or recipient category. 
       FIG. 4  shows a typical communications network  6 ,  10  that comprises or is connected to a distributed system according to an embodiment of the invention for profiling actual or potential respondents. The respondents communicate with the network through terminals, such as  2 ,  4 . In the arrangement shown in  FIG. 4 , the terminal  2  communicates with various network devices via the mobile network  6 , which comprises: a conventional radio and switching network comprising base stations; switches (not shown) arranged in a conventional manner; and a home location register (HLR) for maintaining data relating to subscribers of the network. The mobile network  6  also comprises a billing system  15  for holding Call Detail Records (CDRs) relating to network services used by subscribers of the network  6  and store-and-forward message servers MMSC, SMSC  14 ,  16  configured to store and forward messages in accordance with conventional methods. The terminal  2  may be a wireless terminal such as a mobile phone, a laptop computer or a PDA. The data messaging system  1  also comprises a WAP gateway  8 , which is typically a network operator&#39;s WAP gateway, and a registration services server S 1 , with which a terminal, typically connected to the Internet  10 , communicates via internet gateway  12  to enable a given potential respondent to subscribe to the profiling service according to embodiments of the invention. 
     In embodiments of the invention it is assumed that the questions utilized to form a profiling network N 1  are available from sources such as exemplary server S 3 , and thence stored in data storage  20  for retrieval by a profiling system S 2  for formulating a profiling network N 1  of questions and for delivery as messages M 1  via the communications network  6 ,  10 ; similarly, the responses M 2  to the questions can be received and stored in database  21 , while the links defining a given profiling network, together with associated link rankings and link weightings can be stored in database  22 . It is to be appreciated that while these databases are shown as distinct entities, they could alternatively be part of an integrated storage system. Similarly, while the profiling system S 2  is shown as being embodied in a single server S 2 , it is to be understood that the profiling system could be distributed between different devices according to the functionality required to a) process the questions, b) form a profiling network, and c) receive and process responses according to the profiling network. Further these different devices on which embodiments of the invention are configured could include web servers and/or store and forward devices such as the SMSC  16  and MMSC  14  shown in  FIG. 4 . The profiling system or the system for characterizing a respondent includes the profiling system S 2  and may include the data storage  20 , the data bases  21  and  22 , and web servers, and store and forward devices. 
     Whilst shown as a mobile network  6  and the Internet  10 , the communications network can be a mobile communication network capable of supporting, for example, one or more of the following communication protocols: GSM (Global System Mobile), WCDMA (Wideband Code Division Multiple Access), GPRS (General Packet Radio Service). In addition to or instead of the mobile communication network, a local area network such as a Wireless Local area network (WLAN) or BlueTooth® (BT) and/or other technologies such as WiMax, Broadcasting over DVB-H (Digital Video Broadcasting—Handhelds), ISDB-T (Integrated Services Digital Broadcasting for Terrestrial television broadcasting), DMB (Digital Media Broadcasting) or broadcasting over cellular can be used. The communication network can be also a combination of two or more technologies i.e. hybrid communication network. The communication network can also be arranged to support generic Internet access using any transport methods. The questions and the answers given to questions can be transferred in the electrical communication network, for example, as SMS-messages (Short Message Service), MMS-messages (Multi Media Service), Wireless Application Protocol (WAP) pages, Internet pages, HTML (Hypertext Mark-up Language) pages, XHTML (eXtended HTML) pages, IP (Internet Protocol) datagrams, or email letters (electronic mail). 
     In some embodiments of the invention it is assumed that the user of the terminal  2  is a subscriber of the profiling service according to embodiments of the invention, and that subscribers have entered data indicative of at least some of demographic data, preferences and interests, these data being received and stored by the registration server  51  in the subscriber database  24 . As described above, the subscriber database  24  can be associated with a HLR for the mobile network  6 : in a preferred arrangement, the preference data can be stored in a logically distinct storage area to that in which the network services and subscription data are stored, thereby decoupling the storage of preference data from the storage of the profiling network data. Alternatively the user can choose not to enter any preference data, in which case messages can be selected at random and a profile built up on real time (on the fly) based on responses to the messages. 
     Turning now to  FIG. 5 , an arrangement of the profiling system S 2  will now be described in more detail: in addition to standard CPU, memory, data bus, Input/Output ports, data storage, and operating system programs, the server S 2  comprises various bespoke software components  501 ,  503 ,  505 ,  507  which retrieve data from the various databases  20 ,  21 ,  22  in order to generate a network of linked questions and categories, to formulate messages comprising the questions, and to processes responses from recipients thereof in order to trace paths through the network N 1  according to embodiments of the invention. More specifically, the network generating component  501  queries database  20  to retrieve questions and categories stored therein, and, on the basis of rules associated with the questions, creates links between the questions and categories. As described briefly above with reference to Phase  102 , creation of a profiling network can be triggered at any time, and on the basis of events such as receipt of a certain number of questions from a given source S 3 ; receipt of a certain number of responses from respondents; an amount of time having passed since the network N 1  was last created; receipt of a new or amended set of inter-question linking rules and/or link rankings and/or link weightings; and/or manual triggers from whichever entity is responsible for managing generation of the profiling network N 1 . The profiling network N 1 , specifically the links, link rankings and link weightings, where appropriate, between the questions and categories making up the network N 1  so created is then stored in the database  22 , preferably together with a profiling network identifier and a timestamp indicating a time at which the network N 1  was created. 
     Further, the links can be derived on the basis of data related to the answers given to the questions, as identified by the message processing component  505 , described below. Data related to an answer can include for example: the content of the answer, a location where a recipient was situated when giving the answer, a point of time (a time of day, a day of week, etc) when the answer has been given, and/or a temporal delay from a moment of delivering the question to a recipient to a moment when the answer has been given. Such automated derivation of the links based on feedback from responses to questions can be performed by the linking component  503 , which can additionally set several links between questions Q 1 , Q 2 , Q 3 , Q 4  . . . on the basis of data related to an answer given to the question Q 1 . The information that indicates how the links are to be set can be included, for example, in metadata associated with the question Q 1 . The linking rules so derived can be stored in the database  20 , for future use by the network generating component  501  or can trigger the network generating component  501  to perform real time generation of a profiling network N 1 . Yet further, links can be associated with time-to-live conditions. For example, a link may be defined to be valid only for a limited time interval after setting the link and to be removed after the limited time interval has elapsed. 
     Turning now to the distribution of the questions to recipients, the message processing component  505  is arranged to retrieve questions from the database  20  and formulate messages M 1  associated therewith for transmission to recipients via the communications network. In an arrangement according to an embodiment of the invention, the message processing component  503  is arranged to select one or more recipients to be targets of a predetermined action as a response to a situation in which rankings of the recipient categories fulfill a pre-determined condition. The pre-determined action can be, for example, an advertisement campaign related to a specified product or service, an offer to provide a specified product or service for a reduced price, or sending a set of pre-determined questions to the selected recipients in order to collect further information about the selected recipients. In addition the message processing component  505  is arranged to process received responses M 2  to the questions (i.e. answers to questions), and to store the responses, in association with an identifier associated with the respondent, in a database  21  for use by the network processing component  507  and the linking component  503  in the manner described above. 
       FIG. 6   a  shows an exemplifying profiling network N 1 , according to which links to questions Q 1 -Q 10  and to recipient categories C 1 -C 3  have been set by the network generating component  501  on the basis of linking rules stored in the database  20 . For example, a question Q 1  can be answered with three alternative answers A 1 ( 1 ), A 1 ( 2 ), and A 1 ( 3 ). For example Q 1  can be “Do you use milk products?”, A 1 ( 1 ) can be “Yes, very much”, A 1 ( 2 ) can be “Yes quite a lot”, and A 1 ( 3 ) can be “A little”. It can be seen from  FIG. 6   a  that Q 1  has a link to Q 6 , to Q 7 , and to Q 8  when Q 1  is answered with A 1 ( 1 ), Q 1  has a link only to Q 2  when Q 1  is answered with A 1 ( 2 ), and Q 1  has a link only to Q 9  when Q 1  is answered with A 1 ( 3 ). Each of these links is associated with a link value in the manner described above, with a configurable value specified in the database  20 . In addition each of the links can be associated with link weightings, which weights the various links relative to one another. The questions Q 6 , Q 7 , and Q 8  can be, for example, questions that are used for surveying what kind of milk products are being used by a recipient or recipients that answers/answer the questions Q 1 -Q 10 . In this exemplifying case, importance is given to questions that are used for surveying what kind of milk products are being used when a question “Do you use milk products?” is answered with “Yes, very much”. The other links can be set in the same way, so that for example, Q 10  has a link to recipient categories C 2  and C 3  when Q 10  is answered with A 10 ( 1 ). 
     A network may also have links from a category to a question. A high value for a certain category may increase the importance of a question, and the answer given to that question. Similarly, a category may be linked to another category, thereby increasing or decreasing the ranking of that category. Links emanating from categories and links between questions may be used to reinforce or weaken a certain trend in the ranking of the categories. The links may reinforce a trend if the answers provided to questions are internally consistent, e.g. a high ranking on preference for public transport and a high ranking on environment mindset. The links may weaken a trend if the answers are contradictory, e.g. a high ranking on both environment mindset and desire to drive an SUV. 
     In the foregoing, each link that set according to an answer to a question is a “positive link” that gives importance to a linked question or recipient category. It is also possible that a link is a “negative link” that decreases the importance of a linked question or recipient category, whereby a certain answer to a certain question decreases importance, i.e. ranking of another question or a recipient category. Such link values can be pre-specified or specified on the basis of response messages; for example, in relation to the latter scenario, a lack of answer can be defined to represent a situation in which no link is set or the lack of answer can be defined to correspond to setting a link in a same manner as an answer. For example, a link from Q 3  to Q 6  can be conditional upon Q 3  being answered with A 3 ( 1 ), links from Q 3  to Q 9  and to Q 10  can be conditional upon Q 3  being answered with A 3 ( 2 ), and a link from Q 3  to Q 8  can be conditional upon a null response in respect of Q 3 . 
     In the profiling network N 1  created by the network generating component  501  and shown in  FIG. 6   a , a ranking is assigned to each question on the basis of link rankings associated with answers to other questions that have a link to that question. For the particular implementation shown in  FIG. 6   a , questions Q 1 , Q 3 , Q 5  are not pointed to by any links and thus these questions Q 1 , Q 3 , Q 5  cannot inherit rankings from any other questions. In order to avoid a trivial solution in which all the link rankings of the questions Q 1 -Q 10  and of the recipient categories C 1 -C 3  are zero, initial rankings expressed as initial values are assigned to at least the non-pointed questions Q 1 , Q 3 , Q 5 . The initial rankings can be a same value (a real number) for all the questions Q 1 , Q 3 , Q 5  or question-specific initial rankings can be assigned to different questions Q 1 , Q 3 , Q 5 . The question-specific initial rankings can be determined, for example, on the basis of demographic data related to a recipient or recipients. 
     It is also possible to assign constant or question-specific initial rankings to all the answers to questions Q 1 -Q 10  and to assign constant or recipient category-specific initial rankings to all the recipient categories C 1 -C 3 . Without limiting generality, it can be assumed that for questions having no initial link from another question, the initial ranking R 0 (Q 1 ) is 0. The same applies for the recipient categories. It is also possible that a certain question or a certain recipient category has a negative initial ranking. A negative initial ranking means a purposive reduction of importance of an answer to a particular question or recipient category (and of answers to those questions and/or recipient categories that are pointed by that question or recipient category provided that a higher value of link ranking is defined to mean higher importance (by contrast if a lower value of link ranking were defined to mean higher importance, the situation would be reversed)). 
     As described above, whilst the network generating component  501  creates a network N 1  of the form shown in  FIG. 6   a  based on the linking information, the actual paths through the network N 1 , and thus actual rankings R(Q 1 )-R(Q 10 ) associated with paths and categories linked thereto, are calculated by the network processing component  507  when responses to the questions have been received so as to generate category values based on the actual path traced through the profiling network N 1 . An example of the paths traced through the network N 1  is shown in  FIG. 6   b , as indicated by the fact that certain of the dotted lines shown in  FIG. 6   a  are now presented as solid lines. 
     As an alternative, the profiling network N 1  can be pre-processed, that is to say that hypothetical paths can be traced through the network N 1 , each representing a set of answers relating to one or more respondents, thereby enabling any given respondent to be profiled on the basis of his answers in an expedient fashion. Whilst either situation is possible, for illustrative purposes it will be assumed that the responses have been received from respondents tracing the paths indicated in  FIG. 6   b.    
     The rankings of the questions Q 1 -Q 10 , respectively, can be calculated, for example, as follows: 
         R ( Q 1)= R   0 ( Q 1), 
         R ( Q 2)= R   0 ( Q 2), 
         R ( Q 3)= R   0 ( Q 3), 
         R ( Q 4)= R   0 ( Q 4), 
         R ( Q 5)= R   0 ( Q 5),  (1)
 
         R ( Q 6)= R   0 ( Q 6)+ R ( Q 1)+ R ( A 1(1))/3 +R ( Q 3)+ R ( A 3(1)), 
         R ( Q 7)= R   0 ( Q 7)+ R ( Q 1)+ R ( A 1(1))/3 +R ( Q 2)+ R ( A 2(2))/2 +R ( Q 4)+ R ( A 4(2))/2 +R ( Q 6)+ R ( A 6(2))/2, 
         R ( Q 8)= R   0 ( Q 8)+ R ( Q 1)+ R ( A 1(1))/3 +R ( Q 2)+ R ( A 2(2))/2, 
         R ( Q 9)= R   0 ( Q 9)+ R ( Q 4)+ R ( A 4(2))/2 +R ( Q 8)+ R ( A 8(2))/2, and 
         R ( Q 10)= R   0 ( Q 10)+ R ( Q 5)+ R ( A 5(3))/2. 
     Two things are to be noted in relation to this example:
         1. Only one of the possible answers to any given question has been received from the respondents (taking Q 1 , only answer A 1 ( 1 ) is shown, whereas, as can be seen from  FIG. 6   a , there are two other possible answers, A 1 ( 2 ) and A 1 ( 3 )).   2. The link rankings for particular answers to questions have been equally split between the number of questions to which the answers are linked (e.g. link ranking between questions Q 1  and Q 6  is R(A 1 ( 1 ))/3 because answer A 1 ( 1 ) to question Q 1  is linked to three different questions, Q 6 , Q 7 , Q 8 ).
 
However, and as demonstrated by the simplified example shown in  FIG. 2   b , there is no requirement for the sum of the link rankings associated with all answers to a given question to sum to one, or for the link rankings to be equally distributed between the answers to the questions. Indeed the linking information can be specified in any manner (as mentioned several times above). Furthermore it will be appreciated that typically different answers to any given question will be received from a range of respondents. Indeed, when taking account of the fact that there are three possible answers to Q 1  (A 1 ( 1 ), A 1 ( 2 ), A 1 ( 3 )), and assuming each of the possible answers to be equally weighted, R(Q 6 ) can alternatively be expressed as
       

         R ( Q 6)= R   0 ( Q 6)+ R ( Q 1)+ R ( A 1(1))/3 +R ( Q 3)+ R ( A 3(1)). 
     Working with the set of question rankings of equation (1), the category rankings R(C 1 )-R(C 3 ) of the recipient categories C 1 -C 2 , respectively, can be calculated, for example, as follows: 
         R ( C 1)= R   0 ( C 1)+ R ( Q 7)+ R ( A 7(2)) 
         R ( C 2)= R   0 ( C 2)+ R ( Q 6)+ R ( A 6(2))/2 +R ( Q 10)+ R ( A 10(1))/2, and  (2)
 
         R ( C 3)= R   0 ( C 3)+ R ( Q 8)+ R ( A 8(2))/2 +R ( Q 9)+ R ( A 9(2))+ R ( Q 10)+ R ( A 10(1))/2 +R   0 ( Q 5)+ R ( A 5(3))/2. 
     The network processing component  507  is arranged to profile respondents into the recipient categories C 1 -C 3  on the basis of the category rankings R(C 1 )-R(C 3 ) calculated from the responses, and a measure of correlation of a given respondent with each category is given by the values output in relation to equations (2). Thus the output of equations (2) indicates which one of the recipient categories C 1 -C 3  matches best with the recipient or recipients. 
     If for example R(C 1 )&gt;R(C 2 )&gt;R(C 3 ), the recipient category C 1  matches best with the recipient or recipients and the recipient category C 2  matches secondly best with the recipient or recipients (if a higher value of ranking is defined to mean higher importance). If for example R(C 1 )=R(C 2 )&gt;R(C 3 ) and there is a need to select one recipient category, the selection between C 1  and C 2  can be made, for example, on the basis of demographic or other data related to the recipient or recipients. 
     It is also possible to select a pricing structure that is used for pricing services or products on the basis of rankings of the recipient categories calculated for a recipient or recipients. For example, a mobile operator that is financed with e.g. commercials related to outdoor activities may use more customer-friendly pricing policy for those subscribers (recipients) whose ranking of a recipient category “interested in outdoor activities” is above a pre-determined limit value than for other subscribers in order to maintain and strengthen customer connections with those subscribers who are good targets for advertising campaigns distributed by the mobile operator. It is also possible to select or tailor an action that will be targeted to one or more recipients on the basis of a ranking assigned to a certain recipient category or rankings assigned to certain recipient categories. 
     For example, the recipient category may be “Environmental mindset”, as exemplified in  FIG. 2   a . An advertising campaign related to large cars with a high gas consumption is targeted preferably to recipients having the ranking below a first pre-determined limit value, an advertising campaign related to medium cars with a moderate gas consumption is targeted preferably to recipients having the category ranking above the first pre-determined limit value but below a second pre-determined limit value, and an advertising campaign related to small cars with a low gas consumption is targeted preferably to recipients having the category ranking above the second pre-determined limit value. Identification of respondents having category values above the predefined limits can be performed by the network processing component  507 . 
     In a method according to an embodiment of the invention, the rankings of respondents in respect of the various categories are sent to an external device in order to enable the external device to select the one or more recipients to be targets of a pre-determined action as a response to a situation in which the category rankings of the recipient categories fulfil a pre-determined condition. 
     As described above, a profiling network N 1  is created on the basis of linking information stored in the database  20  (or specified in real-time, as a network is being built). Thus, whilst the database  20  might contain a set of questions relating to a variety of different products, when a profiling network N 1  is being generated in relation to a given product type, the linking rules are likely to specify a type of question, namely one suitable to the given product type, so as to generate a network of questions that are relevant to the product in question.  FIG. 7  shows a diagram illustrating an alternative set of responses for a profiling network N 1  similar to that shown in  FIG. 6   a . Inspection of  FIG. 7  shows that, while present in the database  20 , questions Q 8  and Q 9  have been omitted from the network N 1  because these questions are not considered relevant from the viewpoint of the given product; the database may include a rule to this effect in the database  20 , which, when processed by the network generating component  501 , causes the network N 1  to be built without these questions. For example, the product in question may relate to food (and the questions relate to eating habits), whereas the questions Q 8  and Q 9  may relate to motor oils. 
     It is also possible that one or more questions are excluded from the network N 1  because an advertiser, who has ordered an advertisement campaign in relation to a given product, is not willing to pay for messages containing questions Q 8  and Q 9  to be sent to recipients. For example, in the situation shown in  FIG. 7  the advertiser might have been unwilling to pay for answers given to the questions Q 8  and Q 9 . 
     For the example shown in  FIG. 7 , which represents a particular set of responses received (in respect of a profiling network similar to the profiling network N 1  of  FIG. 6   a , but without questions Q 8  and Q 9 ), the rankings of the questions can be calculated, for example, as follows: 
         R ( Q 1)= R   0 ( Q 1), 
         R ( Q 2)= R   0 ( Q 2), 
         R ( Q 3)= R   0 ( Q 3), 
         R ( Q 4)= R   0 ( Q 4), 
         R ( Q 5)= R   0 ( Q 5),  (3)
 
         R ( Q 6)= R   0 ( Q 6)+ R ( A 1(1))/2 +R ( Q 1)+ R ( A 3(1))+ R ( Q 3), 
         R ( Q 7)= R   0 ( Q 7)+ R ( A 1(1))/2 +R ( Q 1)+ R ( A 2(2))+ R ( Q 2)+ R ( A 4(2))+ R ( Q 4)+ R ( Q 6)+ R ( A 6(2))/2 2, and 
         R ( Q 10)= R   0 ( Q 10)+ R ( A 5(3))/2 +R ( Q 5). 
     The rankings of the recipient categories C 1 -C 2  can be calculated, for example, as follows: 
         R ( C 1)= R   0 ( C 1)+ R ( A 7(2))+ R ( Q 7), 
         R ( C 2)= R   0 ( C 2)+ R ( A 6(2))/2 +R ( Q 6)+ R ( A 10(1))/2 +R ( Q 10), and  (4)
 
         R ( C 3)= R   0 ( C 3)+ R ( A 10(3))/2 +R ( Q 10)+ R ( Q 5(3))/2 +R ( Q 5). 
     By comparing equations (3) and (4) with equations (1) and (2) it can clearly be seen that the category rankings R(C 1 ), R(C 2 ), and R(C 3 ) may have different values when Q 8  and Q 9  are omitted from the network N 1  even if the initial rankings R 0 (Q 1 )-R 0 (Q 10 ) and R 0 (C 1 )-R 0 (C 3 ) were the same in both networks. 
     As mentioned above, in addition or as an alternative to link rankings, links may carry link weightings. When link weighting information is specified for a link from a first node to a second node, the network processing component  507  is arranged to multiply link ranking and/or ranking of the first node with a link weight factor so as to generate a value to be added to the value of the second node. 
       FIG. 8  shows a further alternative profiling network N 1 , comprising six questions, each being linked to other questions and categories according to specified linking rules. The figure shows the four possibilities of linking questions and recipient categories. The ranking of at least one recipient category depends on the ranking of a question that has a link to the category (in this example category C 1  depends on question Q 5 ) and the ranking of at least one question depends on the ranking of another question linked to it (in this example question Q 5  depends on question Q 2 ). As shown in  FIG. 8 , the ranking of at least one of the questions depends on not only the rankings of those other questions that have a link to that question but also on the rankings of those recipient categories that have a link to that question (in this example question Q 6  depends on C 2 ). Additionally, the ranking of at least one of the recipient categories depends on not only the link rankings of answers to questions that have a link to that recipient category but also on rankings of those other recipient categories that have a link to that recipient category (in this example category C 2  depends on category C 1 ). It is also feasible that two recipient categories are linked via a question. In  FIG. 8  this would be realised by a link emanating from Q 6  and connecting to C 1 . 
     Each link has been associated with a link weight factor, e.g. w(Q 4 , Q 1 ) that can be used for increasing or decreasing a link value from a pointing question (or recipient category) to a pointed question (or recipient category). Values of the link weight factors can be defined, for example, on the basis of demographic data related to the recipients. The equations for the rankings can be formulated, for example, as follows: 
         R ( Q 1)= R   0 ( Q 1), 
         R ( Q 2)= R   0 ( Q 2)+ w ( Q 2 ,Q 6)× R ( Q 6),
 
         R ( Q 3)= R   0 ( Q 3), 
         R ( Q 4)= R   0 ( Q 4)+ w ( Q 4 ,Q 1)× R ( Q 1)+ w ( Q 4 ,Q 3)× R ( Q 3),  (5)
 
         R ( Q 5)= R   0 ( Q 5)+ w ( Q 5 ,Q 1)× R ( Q 1)+ w ( Q 5 ,Q 2)× R ( Q 2),
 
         R ( Q 6)= R   0 ( Q 6)+ w ( Q 6 ,Q 5)× R ( Q 5)+ w ( Q 6 ,C 2)× R ( C 2),
 
         R ( C 1)= R   0 ( C 1)+ w ( C 1 ,Q 5)× R ( Q 5), and
 
         R ( C 2)= R   0 ( C 2)+ w ( C 2 ,Q 4)× R ( Q 4)+ w ( C 2 ,C 1)× R ( C 1).
 
     Equations (5) cannot be solved directly in the same manner as equations (1) and (2), and equations (3) and (4), because the ranking R(Q 2 ) depends on the question ranking R(Q 6 ) that depends on the question ranking R(Q 5 ) that depends in turn on the question ranking R(Q 2 ), i.e. there is at least one closed loop of links. Equations (5) can be presented in the matrix form: 
       ( I−A )× R=R   0 ,  (6)
 
     where R is a ranking vector [R(Q 1 ), R(Q 2 ), R(Q 3 ), R(Q 4 ), R(Q 5 ), R(Q 6 ), R(C 1 ), R(C 2 )] T  ( T =transposition) for the questions and categories, R 0  is a known initial ranking vector [R 0 (Q 1 ), R 0 (Q 2 ), R 0 (Q 3 ), R 0 (Q 4 ), R 0 (Q 5 ), R 0 (Q 6 ), R 0 (C 1 ), R 0 (C 2 )] T , I is a unit matrix, and A is a matrix whose non-zero elements are the link weight factors, e.g. w(C 2 , C 1 ), presented in equations (5). Equation (6) can be solved with standard methods of the linear algebra, e.g. by forming an inverse matrix (I−A) −1  or with an iterative method. 
     Whilst the link rankings associated with the various answers to the questions are not shown in  FIG. 8  and do not appear in equations (5), it will be appreciated that the ranking of any given question or category may inherit the link ranking information of links connected to that question or category on the basis of, for example, the relationships expressed in equation (1). 
       FIG. 9  shows an example profiling network N 1 , for which responses have been received in relation to questions Q 1 , Q 2 , Q 4 , Q 5 , Q 6 , the links between these questions and categories C 1 , C 2  having been created entirely on the basis of responses received to questions sent by the message processing component  505 . More specifically, the message processing component  505  has received N 1  messages by way of response A 1 ( 1 ) to question Q 1 ; M 1  messages by way of response A 1 ( 2 ) to Q 1 ; N 2  messages by way of response A 2 ( 1 ) to question Q 2 ; M 2  messages by way of response A 2 ( 2 ) to Q 2 ; N 3  messages by way of response A 3 ( 1 ) to question Q 3 ; M 3  messages by way of response A 3 ( 2 ) to Q 3 ; N 4  messages by way of response A 4 ( 1 ) to question Q 4 ; N 5  messages by way of response A 5 ( 1 ) to Q 5 ; N 5  messages by way of response A 5 ( 2 ) to Q 5 ; and N 6  messages by way of response A 6 ( 1 ) to question Q 6 . 
     In this example the link rankings assigned to respective links between questions and categories is calculated by the linking component  503  on the basis of the total number of responses received and numbers of responses matching the various possible answers to a respective question. Thus in the case of answers A 1 ( 1 ) and A 1 ( 2 ) to Q 1 , the link ranking associated with A 1 ( 1 ) is N 1 /(N 1 +M 1 ) and that associated with A 1 ( 2 ) is M 1 /(N 1 +M 1 ).  FIG. 9  can be interpreted, for example, in such a way that there are N 1  parallel links from Q 1  to Q 4 , M 1  parallel links from Q 1  to Q 5 , N 2  parallel links from Q 2  to Q 5 , etc. 
     The equations for the question and category rankings can be formulated, for example, as follows: 
         R ( Q 1)= R   0 ( Q 1), 
         R ( Q 2)= R   0 ( Q 2), 
         R ( Q 4)= R   0 ( Q 4)+ w ( Q 4 ,Q 1)× N 1/( N 1 +M 1)+ R ( Q 1),  (7)
 
         R ( Q 5)= R   0 ( Q 5)+ w ( Q 5 ,Q 1)× M 1/( N 1 +M 1)+ w ( Q 5 ,Q 2)× N 2/( N 2 +M 2)+ R ( Q 1)+ R ( Q 2),
 
         R ( Q 6)= R   0 ( Q 6)+ w ( Q 6 ,Q 2)× M 2/( N 2 +M 2)+ R ( Q 2),
 
         R ( C 1)= R   0 ( C 1)+ w ( C 1 ,Q 5)× N 5/( N 5 +M 5)+ R ( Q 5), and
 
         R ( C 2)= R   0 ( C 2)+ w ( C 2 ,Q 5)× M 5/( N 5 +M 5)+ w ( C 2 ,Q 6)+ R ( Q 5)+ R ( Q 6).
 
     Any given link weight factor, e.g. w(Q 4 , Q 1 ), shown in  FIG. 9  can be set, for example, on the basis of demographic data related to the recipients and/or a ratio between a number of recipients who have answered a certain question and a total number of recipients to whom this question has been delivered. For example, in a case in which the question Q 1  has been delivered to NQ 1  recipients the link weight factors w(Q 4 ,Q 1 ) and w(Q 5 ,Q 1 ) can be set as w(Q 4 ,Q 1 )=w(Q 5 ,Q 1 )=(N 1 +M 1 )/NQ 1  because Q 1  has been answered by N 1 +M 1  recipients. This exemplifying way of setting the link weight factors corresponds to providing  FIG. 9  with a “sink” that does not have any links to questions and to recipient categories, and a link pointing from a question to the “sink” is set each time when a recipient does not answer a question, i.e. a link from a question to the “sink” corresponds with the “no answer”-case. 
     The link rankings that can be calculated from equations (7) can be interpreted to represent average link rankings for all those recipients that have answered the questions Q 1 , Q 2 , Q 4 , Q 5 , and Q 6 . 
     ADDITIONAL DETAILS AND MODIFICATIONS 
     Whilst in the above embodiments the content items are shown as messages with content that can be paraphrased as explicit or implicit questions, it is to be appreciated that the questions could comprise data having links (URL) to web sites and the like, and for which, clicking on a given URL has the effect of navigating the recipient to the web site. The web site can have rules associated therewith, which determine a response based on the user action. There might be several possible responses, each associated with a particular URL, which are stored in the database  22  and processed in the manner described above. Further, each of the content items, in this case URLs to web sites, can be linked to other URLs to form the profiling network N 1  in any of the manners described above. 
     As described above, the profiling system S 2  comprises a set of computer software components, and these can be e.g. created in accordance with a procedural programming language or an object oriented programming language. 
     The components so created can be stored in a computer readable medium and/or distributed over a network by means of conventional transport techniques. The computer readable medium can be e.g. a CD-ROM (Compact Disc Read Only Memory) or a RAM-device (Random Access Memory). 
     A profiling network can be set up using a display attached to a computer. Nodes can be arranged on the display using for example a pointing device such as a mouse. The pointing device may allow to display a drop-down menu showing options for setting characteristics of the node, such as the type (question node or category node). The pointing device may also be used to select two nodes and set a link between them. Using a similar drop-down menu, properties may be assigned to each link, such as ranking, weighting and dependence on a specific answer. The display may show a an image of the network is provided by  FIG. 6   a  or  8 . The network can be stored in the database  22  as shown in  FIG. 5 . 
     While there have been shown and described and pointed out fundamental novel features of the invention as applied to embodiments thereof, it will be understood that various omissions and substitutions and changes in the form and details of the processes and devices described may be made by those skilled in the art without departing from the inventive idea defined in the independent claims. For example, it is expressly intended that all combinations of those process steps or device elements which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that process steps and device elements shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. The specific examples provided in the description given above should not be construed as limiting. Therefore, the invention is not limited merely to the embodiments described above, many variants being possible without departing from the inventive idea defined in the independent claims.