Patent Publication Number: US-7596552-B2

Title: Method and system for extracting web data

Description:
RELATED APPLICATIONS 
     This application is a division of U.S. patent application Ser. No. 11/364,169, filed on Mar. 1, 2006, which claims the benefit of U.S. Provisional Patent Application No. 60/705,442, filed on Aug. 5, 2005, the contents of which are hereby incorporated by reference. 
    
    
     FIELD AND BACKGROUND OF THE INVENTION 
     The present invention relates generally to an apparatus and method for public attitude analysis. More particularly but not exclusively, the present invention relates to an apparatus and a method for extracting and analyzing public attitude relevant data. 
     Modern organizations spend billions of dollars on Public Relations (PR) and advertisement campaigns in order to bring to the public a message, create a positive atmosphere, and influence stakeholders, opinion leaders and customers. 
     However, measuring the impact imposed by such campaigns on the public is very difficult. 
     Traditional methods for measuring or predicting the impact imposed by public campaigns on the public are inherently limited. 
     For example, Consumer marketing research includes both attitudinal and behavioral market research. Consumer marketing research generally refers to the study of consumers and their purchasing habits and activities. 
     Attitudinal research generally includes studies that focus on understanding consumers and how consumers make purchasing decisions. Attitudinal research can be defined as research that represents a person&#39;s ideas, convictions or liking with respect to a specific object or idea. Opinions are essentially expressions of attitudes. Consequently, attitudes and opinions can be used almost interchangeably to represent a person&#39;s ideas, convictions or liking with respect to a specific object or idea. Collecting consumer purchasing information allows, for example, product manufacturers, to drill down to human purchasing dispositions. Attitudinal research may assist in determining the likelihood of product purchase, how future products can be improved, whether product changes are acceptable, etc. 
     Behavioral research can be defined as the study of consumer behavior. Behavioral research studies what people do, that is, how people act. 
     Behavioral data, reflecting what consumers actually purchase in the marketplace, as opposed to what researchers infer consumers will or will not purchase, has always been available. However, comprehensive behavioral data is not always easy to capture for a variety of reasons. 
     The field of consumer marketing research which includes attitudinal and behavioral market research requires gathering data related to, for example, consumer attitudes and consumer behavior, in order to analyze such attitudes and behavior. Consumer data may be gathered through the distribution of incentive items activated via participation in consumer research programs and consumer surveys, such as the ones described in U.S. Patent Publication 20030070338, entitled: “Removable label and incentive item to facilitate collecting consumer data”. However, incentive based methods may produce biased results. 
     Prior art methods for measuring public attitudes include conducting polls on a presumably representative sample of target audiences. For example, U.S. Pat. No. 3,950,618 entitled: “System for Public Opinion research” describes an automatic system for processing a public opinion poll. However, such methods are based on an assumption that such samples are indeed representative of the target audiences. 
     Another popular prior art method for evaluating public attitudes which is very often employed involves focus group techniques. A focus group is a group of people, presumed to be representative of a target population, such as parents or customers, gathered to provide answers to open-ended questions on specific topics and share their opinions. 
     Prior Art lacks methods for capturing public attitudes which do not rely on the careful selection of a representative sample or the actual behavior and the availability of comprehensive data pertaining to the actual behavior. 
     Prior art has so far failed to incorporate public attitude spread by word of mouth, specifically as far as the Internet is concerned. The web added a new dimension to the media mix—online news groups, discussion groups, forums, chats and blogs—are all forms of communications that did not exist ten years ago, and today they are an inseparable part of the media mix. The public is an inseparable part of the media. The public is fed from the media and feeds the media through its new means of communication. 
     There is thus a widely recognized need for, and it would be highly advantageous to have an apparatus and method for extracting and analyzing public attitude data which is devoid of the above limitations. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the present invention there is provided an apparatus for providing an analysis of attitudes expressed in web sites, comprising: a collector for collecting attitude-data in relation to a predetermined subject from at least one pre-selected web site, the attitude-data containing attitudes in relation to the predetermined subject, a processor, associated with the collector, for processing the attitude data so as to generate an attitude analysis, and an outputter, associated with the processor, for outputting the attitude analysis, thereby to provide an indication of attitudes being expressed in the web content in relation to the predetermined subject. 
     According to a second aspect of the present invention there is provided an apparatus for crawling web content to provide data for attitude analysis of attitudes expressed in the web content in relation to a predetermined subject, the apparatus comprising a crawler, configured to crawl a plurality of pre-selected web sites, for collecting attitude-data from the web sites, the attitude data comprising attitudes relating to the predetermined subject, the crawler being further configured to provide the attitude data to a predetermined location for the attitude analysis. 
     According to a third aspect of the present invention there is provided a method for analyzing attitudes expressed in web content, the attitudes being in relation to a predetermined subject, comprising: automatically collecting attitude data from at least one pre-selected web site, the attitude-data expressing a plurality of attitudes in relation to the predetermined subject, electronically processing the attitude data so as to generate attitude information indicative of the plurality of attitudes, and outputting the attitude-information, thereby to provide an analysis of the attitudes in relation to the predetermined subject. 
     According to a fourth aspect of the present invention there is provided a device for interactive setting of a data collection policy using a web page display, comprising a web page displayer, for displaying a web page to a user, operable for defining a data collection policy in relation to the web page. Preferably, the device&#39;s web page displayer is further operable to define a specific data collection policy in relation to a respective region of the web page. 
     Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The materials, methods, and examples provided herein are illustrative only and not intended to be limiting. 
     Implementation of the method and system of the present invention involves performing or completing certain selected tasks or steps manually, automatically, or a combination thereof. Moreover, according to actual instrumentation and equipment of preferred embodiments of the method and system of the present invention, several selected steps could be implemented by hardware or by software on any operating system of any firmware or a combination thereof. For example, as hardware, selected steps of the invention could be implemented as a chip or a circuit. As software, selected steps of the invention could be implemented as a plurality of software instructions being executed by a computer using any suitable operating system. In any case, selected steps of the method and system of the invention could be described as being performed by a data processor, such as a computing platform for executing a plurality of instructions. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The file of this patent contains at least one drawing executed in color photograph. Copies of this patent with color photograph(s) will be provided by the Patent and Trademark Office upon request and payment of necessary fee. 
       The invention is herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only, and are presented in order to provide what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice. 
       In the drawings: 
         FIG. 1  is a block diagram of an apparatus for analyzing attitudes expressed in web sites, according to a preferred embodiment of the present invention; 
         FIG. 2  is a detailed block diagram of an apparatus for analyzing attitudes expressed in web sites, according to a preferred embodiment of the present invention; 
         FIG. 3  is an exemplary main forum web page; 
         FIG. 4  is an exemplary forum header web page; 
         FIG. 5  shows an exemplary message header page; 
         FIG. 6  is a flow chart illustrating an implementation of a predefined collecting policy for a specific forum web site, according to a preferred embodiment of the present invention; 
         FIG. 7  shows an exemplary XML format parsed attitude-data bearing page representation, according to a preferred embodiment of the present invention; 
         FIG. 8  is a block diagram illustrating an apparatus for collecting attitude-data from web site(s) according to a preferred embodiment of the present invention; 
         FIG. 9  shows an exemplary collecting policy definer graphical user interface (GUI), according to a preferred embodiment of the present invention; 
         FIG. 10  shows an exemplary Web site page; 
         FIG. 11  shows an exemplary user marked Web site page, according to a preferred embodiment of the present invention; 
         FIG. 12  shows an exemplary relative title position encoding in a change query language script according to a preferred embodiment of the present invention; 
         FIG. 13  shows an exemplary pseudo-code, for crawling a specific web site page, according to a preferred embodiment-of the present invention; 
         FIG. 14  is a flowchart illustrating attitude data processing according to a preferred embodiment of the present invention; 
         FIG. 15  shows an exemplary graphic representation of the results of clustering, according to a preferred embodiment of the present invention; 
         FIG. 16  shows an exemplary graphic representation of the results of correlation measurement according to a preferred embodiment of the present invention; 
         FIG. 17  shows a first graphic representation of attitude-data analysis according to a preferred embodiment of the present invention; 
         FIG. 18  shows a second exemplary graphic representation of attitude-data analysis according to a preferred embodiment of the present invention; 
         FIG. 19  is a flow diagram of an exemplary method for analyzing attitudes expressed in web sites, according to a preferred embodiment of the present invention; 
         FIG. 20  is a flow diagram of an exemplary method for categorizing attitude-data text according to a preferred embodiment of the present invention; 
         FIG. 21  is an exemplary pseudo-code algorithm for clustering concepts relating to attitude-data, according to a preferred embodiment of the present invention; and 
         FIG. 22  is a simplified block diagram of an exemplary architecture of an apparatus for analyzing attitudes expressed in web sites, according to a preferred embodiment of the present invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present embodiments comprise apparatus and method for analyzing public attitudes expressed in web sites or any kind of electronic information found on the web, in a holistic approach. 
     The embodiments, according to the present invention, are based on collecting information found on the web, generally considered an influential medium, where authentic attitudes are expressed daily. The websites are in effect, today&#39;s word of mouth (WOM) as communicated by millions of Internet users. 
     Millions of web users express their views and feelings in online news groups, discussion groups, forums, chat sites, internet blogs etc. All these new means of communication, intensively used by the public today, have become a major part of the media where people are exposed to ideas, products, and messages and where people express their attitudes. 
     Embodiments of the present invention aim at collecting the immense amount of high value authentic data pertaining to people&#39;s attitudes found in Web sites and holistically analyzing the data, so as to provide with high value attitude information. 
     The principles and operation of an apparatus and a method according to the present invention may be better understood with reference to the drawings and accompanying description. 
     Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting. 
     Reference is now made to  FIG. 1 , which is a block diagram of an apparatus for analyzing attitudes expressed in web sites, according to a preferred embodiment of the present invention. 
     An apparatus  1000  according to a preferred embodiment of the present invention comprises a collector  110 . The collector  110  is configured for collecting data, including but not limited to attitude data, containing attitude expression, from pre-selected web site(s)  1100  the attitude data relating to a predefined subject. Preferably, the number of the pre-selected web sites  1100  may reach hundreds of thousands of web sites. 
     The pre-selected web sites typically include Chat sites, Interactive news groups, Discussion groups, Forums, Blogs and the like where people express their views and feelings. For example: Internet users may express their views regarding a proposed tax reform, to be discussed by a government, regarding a new product etc. 
     According to a preferred embodiment, the collector  110  is programmed as a crawler in a spider network, arranged to detect new attitude data in the pre-selected web sites. For tracking the new attitude data added to a pre-selected web site, the collector  110  utilizes a script, written in a change detection language, as described in greater detail herein below. 
     For example, the script may define which parts of a specific page of a pre-selected web site bear a fixed content such as a logo of a firm operating the site, and which parts contain dynamic content, bearing attitude data, such as a continuous flow of user&#39;s messages in a web site&#39;s chat room. 
     In another example, the script may define a comparison to be made by the collector  110  between current content of a page or a part of a page and attitude data previously downloaded from the same page or part of the page. 
     The script may be generated using a collecting policy definer  160 , as described in greater detail herein below, and illustrated using  FIGS. 9 and 10 . 
     The apparatus  1000 , according to a preferred embodiment, further comprises a processor  120 , associated with the collector  110 , used for processing the attitude-data. The processing of the attitude-data may typically include parsing the attitude-data, content analysis techniques, data mining, and other data analysis techniques. These techniques may implement any one of a variety of algorithms, which includes but is not limited to: neural networks, rule reduction, decision trees, pattern analysis, text and linguistic analysis techniques, or any relevant known in the art algorithm. 
     The apparatus  1000  according to a preferred embodiment, further comprises an outputter  130 , associated with the processor, for outputting resultant attitude information based on the processed attitude-data. Preferably, the output information is presented to a user utilizing a set of graphical tools, as described in greater detail herein below. The graphical tools may be implemented as a stand alone desktop application, as a web browser based application, as a client application in a client-server architecture, etc. 
     Preferably, the apparatus further comprises a data-storage  150  where the attitude-data is stored. 
     More preferably the data storage  150  is a data warehouse, provided with a storage area and, preferably, with advanced means for analysis of the attitude-data. In a preferred embodiment, the data warehouse is provided with a set of graphical tools aimed at enabling a user to navigate the processed attitude-data, explore it, and easily find the information the user is interested in. 
     The graphical tools may be implemented in as a desktop application, a web application, or any other known in the art alternative. 
     In a preferred embodiment, the collector  110  may continuously monitor the pre-selected web site(s)  1100 , on a 24 hours a day and seven days a week basis. 
     Optionally, a specific schedule for collecting the attitude-data may be set with respect to specific web site(s). 
     According to a preferred embodiment of the present invention, the collector  110  works in a continuous mode. Preferably, the collector utilizes a change detection language or mechanism, and downloads relevant pages of the pre-selected web site(s), according to a predefined collecting policy. 
     According to a preferred embodiment of the present invention, the collector  110  further includes a crawler. 
     The crawler is responsible for crawling the pre-selected web pages for new data, and for downloading relevant web pages there from. Preferably, the crawler is an open system that has capabilities to download all kind of data on the network including, but not limited to: Web pages, Forums, Discussion boards, and Blogs. 
     Reference is now made to  FIG. 2  which a detailed block diagram of an apparatus for analyzing attitudes expressed in web sites, according to a preferred embodiment of the present invention. 
     An apparatus  2000 , according to a preferred embodiment of the present invention comprises a GUI Manager  210  which manages the interaction with a user of the apparatus  2000 . 
     The GUI Manager  210  includes a Correlation GUI component  201  which is configured to present correlation data pertaining to correlations among phrases having relevance-relationships with a common concept relating to the predefined subject, as found in the attitude data, as described in greater derail herein below. 
     The Correlation GUI component is connected with a correlator  242  which is configured to measure correlation between one or more phrases and a respective common concept relating to the predefined subject, as described in greater detail herein below. The concept may describe an attitude towards the subject such as but not limited to negative, a positive, or a neutral attitude, including any words that do not express a sentiment directly but may be conceptually related in people&#39;s minds. 
     The Correlation GUI is further connected to a Matrix Creator  241  which is configured to a create and populate a N×N Matrix with values indicating distances between correlated phrase, as described in greater detail herein below. 
     The GUI Manager  210  further includes a Clustering GUI component  202  which presents clusters relating to concepts in the attitude data to the user, as described in greater detail hereinabove. The concept may describe any information regarding the subject, such as: attitude towards the subject such as a negative, a positive, or a neutral attitude, as described hereinabove, or other related concepts, people, products, emotions etc. 
     Clustering the concepts may be carried out by a clustering engine  260 , utilizing clustering methods, as described in greater detail hereinabove. 
     Preferably, the Correlation GUI  201  component and the Clustering GUI component  202  are further connected with a Projections engine  230  which graphically positions items representing clusters and correlated phrases on the GUI&#39;s screens, such as the screen presented in  FIG. 15  herein below. 
     The GUI Manager  210  further includes a Trend GUI component  203  which presents the user with trend data. The trend data is generated by a Trend Analyzer  220  which is configured to detect trends in the attitude data. The trend analyzer is fed by a Statistics component  244  which generates statistical data pertaining to the appearing of attitude expressing phrases in the attitude data, as described in greater detail herein below. For example, trend GUI may facilitate the detection of a shift in public discussion of a specific concept, or expression of specific attitudes. 
     The GUI Manager  210  may further include a Statistics GUI component,  205  connected to Statistics component  244 , for presenting the statistics data generated by the Statistics component  244  to the user. 
     The GUI Manager  210  further includes a Quotations GUI component  204  which presents the user with quotations relating to the concepts presented to the user by the correlator GUI  201 , as described hereinabove. The Quotations GUI component  204  is fed by a Quatator  243  which is configured to extract relevant attitude expressing quotations from the attitude data. 
     The Statistics component  244 , the Quatator  243 , the Correlator  242 , and the Matrix creator  241  are connected to a core engine  250  which includes a parser  252 , for parsing the attitude data that is downloaded from crawled pages and a counter  251  for counting the appearances of concepts etc. in the attitude data, as described in greater detail herein below. 
     Reference is now made to  FIG. 3  which shows an exemplary main forum web page. 
     The exemplary main forum web page is a DVD Talk forum main web page. In this example, the crawler is preconfigured for crawling the web site, downloading all messages that appear in the threads (topics) of the site forums. In this example, the crawler first crawls the links in the exemplary main forum web page, to all forum header pages  310  available in the pre-selected web site. Preferably, the crawler is further preconfigured to filter out non-relevant links so as to avoid downloading or attempted downloading of irrelevant pages. 
     Reference is now made to  FIG. 4  which shows an exemplary forum header web page. 
     After the crawler gets the links to the forum header pages from the exemplary main forum page, the crawler crawls relevant threads  410  appearing in each of the header web pages, according to the links  310 . Preferably, the crawler is pre-configured for filtering out non-relevant threads like the general policy and search threads appearing in this example  411 . 
     Reference is now made to  FIG. 5  which shows an exemplary message header page. 
     According to a preferred embodiment of the present invention, for each of the relevant threads  410 , the crawler extracts relevant attitude-data, which contain attitude expressions. As shown in the example page on  FIG. 5 , each message optionally comprises a date, a title, an author, and a message body. 
     Optionally, each message also contains a list of quotes (quotations from other cited messages), and signature. The quotes are marked in the message so that, during his analysis procedure, the user can choose if he wants his analysis to be performed on the messages including the quotes or not. The message signatures (when present) are filtered during the crawling process, in order to avoid skewing the results, as described in greater detail herein below. 
     The data has to be extracted from the page, while omitting all irrelevant information. It is important to remember that there are many types of irrelevant information that may be found on such message pages. The irrelevant information includes but is not limited to: other messages, signatures, html tags, ads etc. and those vary from one site to another. 
     Preferably, the collector  110  implements a predefined collecting policy. The collecting policy may include specific guidelines with respect to specific ones of the pre-selected web sites. These guidelines may define which parts of the pre-selected web site(s) to crawl, in what order, etc. 
     For example, reference is now made to  FIG. 6  which is a flow chart illustrating an implementation of a predefined collecting policy for a specific forum web site, according to a preferred embodiment of the present invention. 
     In a preferred embodiment, the collector  110  uses a HTTP request for downloading the relevant page(s) of the pre-selected web site(s), according to URL addresses. 
     Preferably, the crawler may be further configured for handling relevant aspects of the crawling such as—session objects, login information, cookies, etc. 
     According to a preferred embodiment, the crawler is further responsible for scheduling downloading processes of relevant pages of the pre-selected web site(s) (i.e. request per time quantum per site). 
     In addition, the crawler may be also configured for determining in what order the pages are downloaded. Preferably, network traffic is also carefully monitored by the crawler, with respect to the pre-selected web sites, so as to avoid generating excessive traffic on the web site(s), by carefully scheduling the downloading process. 
     Optionally, the crawler verifies that a pre-defined time interval is kept between one access to a certain web site and another access, so as to try avoiding creation of network overload on the web site. 
     According to a preferred embodiment, several crawlers are employed in parallel in the downloading process and each of the crawlers is configured for downloading respective web site(s). 
     According to a preferred embodiment of the present invention, the collector  110  further includes a parser. Once a relevant page is downloaded by the crawler, it may be forwarded to the parser. 
     The parser is configured for parsing the relevant page and for extracting relevant attitude data from the relevant page or links top pages that contain this relevant data. 
     Relevant data sections may be found on the message text, message title, date, author and other places on the page. The parser is further configured for filtering out irrelevant information on the page, like html tags, adds, header, footer etc. 
     In a preferred embodiment of the present invention, the parser may apply a script, customized specifically by a user for each web site, to extract relevant attitude-data from the web site, while filtering out non-relevant or corrupted data. The non relevant data may include but is not limited to: hidden data such as html tags and scripts that are mainly used for page definition and page control, and non relevant content data like texts that are presented on the web page but are not relevant with respect to the attitude-data, such as a page number, a commercial footer, a banner etc. 
     In a preferred embodiment of the present invention, after irrelevant data is removed and only the relevant attitude-data remains in the web page, the parser converts the web page into a mark-up language format representation. Optionally, the mark-up language is XML. In the mark-up language format representation, relevant data and metadata may be encoded in a searchable and indexable format. 
     According to a preferred embodiment, specific types of data, found on the web page, are handled by the parser in a specific manner, in accordance with a predefined policy. 
     For example, in message boards, very often a user issues a new message, citing a message previously posted by another user. The cited message appears in the new message. However, for analysis purposes it may be ignored, as it may skew the statistics of the results if it is counted twice in spite of the fact it is not a new unique message. In another example, message signatures may also skew the results, as they are identical for all messages a specific user issues. During analysis, the words appearing in the signatures may skew the statistics. 
     Thus the parser may be configured to recognize and ignore parts of messages such as quotations from other messages or signatures. 
     Reference is now made to  FIG. 7  which shows an exemplary semi-XML format parsed attitude-data bearing page representation, according to a preferred embodiment of the present invention. The provided example illustrates the encoding of page including a community name (DVD Talk in the example)  710 , a forum name (DVD Exchange in the example)  720 , a message title  730 , a date  740 , a author  750  and the body of the message  760  are encoded in a searchable and indexable XML language format representation. 
     In a preferred embodiment of the present invention, the collector  110  further comprises a data integrator (updater). 
     The data integrator is responsible for verifying that only relevant pagesdocuments crawled from the internet are stored in the data storage  150 . The data integrator checks that a current document does not already exist in the data storage  150 . The data integrator is also responsible for checking the completeness of the download, i.e that no errors are found, the parsing is carried out successfully, etc. 
     When the Updater identifies that all pages are downloaded (For example, according to the expected number of pages that should be downloaded), it crawls all the user profiles, and then folds the whole downloaded data set to the data storage  150  or calls another component, say a utility of a data base management system (DBMS), for folding the data to the data storage  150 . 
     The data integrator may be configured for integrating the attitude data into a complete and non-redundant attitude data. The integration of attitude data by the data integrator may include but is not limited to: handling redundancy of data, preventing keeping duplicate page etc. Integrating the data may further include ensuring complete download of all relevant data bearing pages of the web site(s), i.e.—that the attitude-data is error free, that the parsing is successfully completed etc. The data integrator may be further configured for indicating when and if all relevant pages are downloaded. 
     In a preferred embodiment, the data integrator is further configured for deciding if an apparent error, detected when downloading a web page, is recoverable or should the web page be regarded as corrupted and be accordingly ignored. 
     The data integrator may be further configured for updating the data storage  150  with the attitude-data, while carrying out the integration of the attitude-data as described hereinabove. 
     According to a preferred embodiment of the present invention, the apparatus  1000  further comprises a collecting policy definer  160  which is associated with the collector  110  and is used for defining the collecting policy. 
     Preferably, the collecting policy may address various aspects of the collecting process. The collecting policy may define which web site(s) or what kind of web sites the collector collects attitude-data from. The collecting policy may provide specific guidelines for crawling through a specific web site. The specific guidelines may define which kinds of data that are found on pages of the web site are to be ignored, in what order should the web site be crawled, how the pages are parsed, how different types of data are marked up, etc. 
     Reference is now made to  FIG. 8  which is a block diagram illustrating an apparatus for collecting attitude-data from web site(s) according to a preferred embodiment of the present invention. 
     An apparatus according to a preferred embodiment of the present invention comprises one or more crawler(s)  801 . Each crawler may be assigned to respective pre-selected web site(s)  800  for crawling, to locate and download relevant web pages carrying attitude-data therefrom. 
     Each of the downloaded web pages is then put in a parsing queue  803  where from, in its turn, the page is parsed by a parser  805 . Preferably, the parser  805  is configured to parse a web page and create a mark-up language base representation of the web page. Preferably, the mark-up language is XML. The parser may be further configured for forwarding the parsed page(s) to an update queue  806 . 
     An apparatus according to a preferred embodiment also includes a data integrator (updater)  807 . Preferably, the data integrator  807  is configured for fetching the parsed pages data from the updates queue  806 , integrating the data by handling redundancy of data, preventing from keeping duplicate pages etc. Integrating the data may further include ensuring complete download of all relevant data bearing pages of the web site(s)—such as next pages, navigation from forum to topic and then to the message itself etc.—utilizing a request queue  809 , ensuring that the attitude-data is error free, verifying that the parsing is successfully completed etc. Finally, the data integrator updates a database (DB) or a data warehouse (DW)  810  with the parsed pages carrying the attitude-data. 
     A preferred embodiment of the present invention may further include a crawl manager/scheduler  811  which manages the crawler(s)  801  and schedules the crawling of pre-selected web page(s) according to the request queue  809 , utilizing a downloads queue  813  to be used by the crawler(s)  801 . Preferably, the request queue is managed by a collecting policy definer  160 , preferably implemented as a management console  815 . 
     This crawl manager/scheduler  811  is responsible for scheduling the download process (i.e. request per time quantum per site), in addition it is responsible for the order of pages being downloaded. 
     Network traffic is carefully monitored by the various web sites, and trying to avoid generating over traffic on the downloaded web sites, a carefully schedule may be implemented for the download process. The Crawl Manager  811  is responsible for the scheduling and verifies that a pre-defined time interval is kept between one access to a certain web site and the other, in that way the generation of network overload on the crawled web sites by the crawling may be avoided. 
     In addition, employing several crawlers  801  together allows parallelism in the downloading process, downloading many web sites in parallel while accessing each one only once in a while. 
     Also, as the ratio of new user post pages (documents) to exiting pages is not very high, an updated list of the new post pages may be maintained and used for further reducing crawling activities on the crawled web sites. 
     Reference is now made to  FIG. 9  which shows an exemplary collecting policy definer graphical user interface (GUI), according to a preferred embodiment of the present invention. 
     According to a preferred embodiment of the present invention, the collecting policy definer  160  includes a graphical user interface (GUI), which graphically facilitates the definition of a collecting policy by a user of the apparatus  1000 . 
     In the exemplary collecting policy GUI of  FIG. 9 , on the top of the screen there is a settings bar where the user inputs the address of the web site page  910  for collecting attitude-data there from, the output file  920  to save the results in, and the page type  930 . 
     Below the setting bar there is a window  950  where the user may provide other definitions. For example: The color coding for each of the marked fields, the date format being used in this particular site (e.g. European, American, or other) and optionally other relevant definitions. 
     Below the window  950  is the main working area of the application  980 . The main working area  980  has the behavior of a browser and loads a web site page so as to allow the user to define the specific collecting policy with regards to the specific web site page. 
     When the page is loaded the user may mark the relevant parts on the page, indicating what section reflects what part of information to be crawled, or optionally, to be ignored. This operation is preferably repeated for each part of a web site (i.e.: forums list, topic list, message pages, author profiles, etc.). 
     According to a preferred embodiment of the present invention, the collecting policy definer  160  is configured to use the definitions made using the GUI, as described hereinabove, for generating a script encoded collecting policy. The collecting policy may specifically define how each element on the page is crawled or parsed. 
     Reference is now made to  FIG. 10  which shows an exemplary Web site page. 
     The exemplary page (http://dvdtalk.com/forum/forumdisplay.php?f=8) is a Forum web site page. The exemplary page has several main parts: a header, headlines, banners, a quick launch area for starting frequently used forums, and a list of forums. 
     Using the GUI of the collecting policy definer  160  the user may graphically select part(s) of the web site page and define a collecting policy for the part(s) as well as for the whole page. 
     Reference is now made to  FIG. 11  which shows an exemplary user marked web site page, according to a preferred embodiment of the present invention. 
     The web site page of  FIG. 10  is now presented having its main parts graphically selected and marks by the user. 
     With regards to the exemplary page, the user may define that only the elements of the list of forums  1110  are to be crawled and parsed. 
     According to a preferred embodiment, each element is regarded by the collecting policy definer  160  as having a position relative to a parent element. 
     In the example of  FIG. 11 , each element  1111 - 1112  of the list of forums  1110  has a relative position with respect to the header of the list  1120 . Consequently, when the absolute position of the header is changed, say when a new advertisement banner is positioned by an operator of the web site, just above the list of forums, the relative position of each element on the list remains the same. 
     Reference is now made to  FIG. 12  which shows an exemplary relative title position encoding in a change query language script according to a preferred embodiment of the present invention. 
     The provided exemplary position is relative to a header of an html table. The table header has fixed position on the page, and the shown exemplary relative title position is encoded in relation to the fixed position. The parser  805  uses the definition provided by the user as illustrated in  FIG. 10-11  and explained herein above, to correctly encode a generic title position relative to the fixed position of the table header. 
     Reference is now made to  FIG. 13  which shows an exemplary pseudo-code, for finding the specific element definition in the collecting policy GUI ( FIG. 9 ) on a specific web site page, according to a preferred embodiment of the present invention. 
     The provided exemplary pseudo-code describes a sequence of steps for collecting policy GUI ( FIG. 9 ) to extract from the exemplary web site page that may be a part of the collecting policy, encoded in a script, based on user provided definitions, as illustrated and explained using  FIGS. 10-11  hereinabove. 
     According to a preferred embodiment of the present invention, the collector  110  is configured for carrying out several steps of processing with regards to the collected attitude-data. 
     Reference is now made to  FIG. 14  which is a flowchart illustrating attitude data processing according to a preferred embodiment of the present invention. 
     According to a preferred embodiment of the present invention, the attitude data is processed in a pipeline mode, wherein each document/message in the crawled web pages undergoes a series of steps that are applied to it in a row. 
     According to a preferred embodiment, Internet sites  1400  are crawled for new messages, bearing attitude-data, based on a script in a change query language as described herein above. 
     Preferably, any given web page may be downloaded using HTTP protocol. However, the page has to be parsed in order to extract its information. This is already the role of the above described parser. 
     The parser may represent the downloaded web page as a XML tree, and apply a change query language script, specifically customized for each web site, to extract the relevant information from it, skipping all the non-relevant info. 
     For example, the change query language may be an Extensible Style sheet Language Transformation XSLT language, which is a language for transforming XML documents into other XML documents. 
     The XSLT script may have the ability to ignore all kind of non relevant data, based on an ad-hoc customization, as described in greater detail herein below, for the collecting policy definer. 
     The relevant pages are downloaded and parsed  1401  to identify their relevant text section and the metadata relating to the new attitude-data such as: title, author, or date, is extracted from the collected attitude-data. 
     The processor  120  may further include a runtime environment which may be further configured for labeling each message/document with relevant metadata. 
     Then, the processor  120 , using an on-line interface, categorizes  1410  relevant texts of the collected attitude-date using supervised approaches. 
     Next, the processor  120  carries out classical text categorization by content, which involves assigning each message/document a list of topics being discussed in it, based on the identification and analysis of issues discussed in the collected attitude data. In addition, processor  120  carries out text categorization by sentiment, which involves assigning each message/document its polarity label (positive, negative or neutral). 
     According to a preferred embodiment of the present invention, the content based categorization of the collected attitude-data may be based on an output generated by a training/testing environment which may be a part of the processor  120 , and may be used to form the model for categorizing the attitude expression, i.e. the logic of how to identify titles, topics, age groups, gender etc, as described in greater detail herein above. 
     Optionally, the processor  120  may utilize one of the text categorization techniques in a range which includes but is not limited to: Feature Selection, Feature filtering, and Training as described in greater detail herein below. 
     In a preferred embodiment, the processor  120  is also configured to carry out text categorization by style technologies. Such technologies may add and categorize vital data about the document author, like his age or his/her gender, without having any direct background knowledge about the author. 
     Categorization by style technologies are based on the idea of analyzing the writing style, the language used by the author, the use of foreign language words etc. to indirectly learn about the author. Learning about the author, the attitude data may be categorized according an age group, gender, etc. 
     Style text categorization may enrich the queries and analysis the end user can perform on the data. Since this style derived information is static, it may be generated in a metadata pre-processing stage as well. 
     According to a preferred embodiment of the present invention the processor  120  may include a Statistics Generator for generating various statistics relating to the collected attitude-data. 
     Preferably, the processor  120  includes data mining tools for mining  1412  the collected and processed attitude-data, so as to provide a user with means for carrying out pattern analysis and trend detection  1430  in the attitude data. 
     According to a preferred embodiment of the present invention, the processor may implement any of the methods described hereinbelow for categorizing the texts of the attitude-data and for further analyzing the attitude-data, say for providing statistics relating to the attitude-data or for mining the attitude-data. 
     The results of the categorization and data mining steps are output and stored in a data storage (a database or a data warehouse)  1420 . 
     Preferably, the processor  120  may further include a concept analyzer, operable by an analyst/user  1450  for concept analyzing  1431  the attitude data, for finding in the attitude-data relevance-relationship(s) between a phrase, comprising one or several words, and a respective concept, as described in greater detail hereinbelow. 
     More preferably the processor  120  may also include a correlation measurer, configured for measuring  1432 , in the attitude-data, correlations among phrases having relevance-relationships with a common concept, and for measuring correlation between one or more of these phrases and the common concept, as described in greater detail herein below. 
     According to a preferred embodiment of the present invention, the processor  120  may further include a quotation extractor, for extracting  1433  from the attitude-data key quotations which are found to be descriptive of a relevance-relationship existing in the attitude-data between a concept and respective phrases (comprising one or more words), as described in grater detail herein below. 
     According to a preferred embodiment, the processor may further include a clusterer. The clusterer may be operable by a user/analyst  1450  for clustering concepts  1434  relating to the attitude-data, as described in greater detail herein below. 
     According to a preferred embodiment of the present invention, the outputter  130  provides a user  1440  or an analyst  1450  with various graphical tools for examining, exploring, and analyzing attitude-information, generated by collecting and processing the attitude-data. Optionally, the graphical tools may be provided as a web application  1442 , so as to allow the user to examine and explore the attitude data remotely via the web. 
     Reference is now made to  FIG. 15  which shows an exemplary graphic representation of the results of clustering concepts in the attitude data, according to a preferred embodiment of the present invention, as described hereinabove. 
     With clustering, individual messages are analyzed for a central attitude and then added a corresponding cluster of attitudes. 
     In the central part of the screen the user can see the generated clusters as circles  1501 , clusters with more messages/documents are denoted as bigger circles, their distance is displayed by their visual layout. Clusters that are in the red-region  1503  are clusters of negative attitude, while positive attitude ones are in the green part  1505 . 
     On the left screen side, the user can see the topic of each cluster  1507 . Clicking on one of the clusters displays to the user a set of relevant message/document citations for each of the clusters. 
     Reference is now made to  FIG. 16  which shows an exemplary graphic representation of the results of correlation measurement according to a preferred embodiment of the present invention. 
     The correlation measurer, discussed hereinabove, measures correlations of relevant phrases for a central concept as well their cross-relationships. An exemplary visualization of results of the measurement is shown in  FIG. 16 . 
     In the center is the main concept (“USA”)  1601  surrounded by words indicating anti-American attitude expression in the web. The colors describe the various phrase types that are related to the central term, and their cross relations, according to a provided legend  1605 . Optionally, the layout algorithm may be based on a SVD (factor analysis) formula combined with MDS (multi dimensional scaling), wherein an n×n matrix is used to measure the distances between each pair among the relevant phrases, n denoting the number of phrases. 
     Reference is now made to  FIG. 17  which shows a first exemplary graphic representation of attitude-data analysis according to a preferred embodiment of the present invention. 
     According to a preferred embodiment the outputter  130  includes a user friendly graphical front end environment for defining and viewing attitude-information. Preferably, there are two types of front end: a desktop application and a web based client. 
     For example, the front end environment may provide a user with means for tracking trends, buzz, and sentiment, which are preferably based on the data warehouse  150  capabilities such a multidimensional data analysis. 
     Users may analyze their company&#39;s\product&#39;s word of mouth over time according to the different markets and vertical markets. Such analysis may prove very beneficial for the users. 
     In addition the user has the ability to compare his company\product to other products or companies in his vertical market or to a benchmark, set according to an industry standard. For example, as illustrated in  FIG. 17 , the user may investigate the concept of the top ten movies  1701 , as depict in a chart showing the trend among the ten most popular in a monthly basis  1703 . 
     Reference is now made to  FIG. 18  which shows a second exemplary graphic representation of attitude-data analysis according to a preferred embodiment of the present invention. 
     Preferably, more advanced capabilities then the ones presented in  FIG. 17  are available for the advanced user. For example, as shown in FIG.  18 —analysis according to gender  1801 , analysis according to age range  1803 , selection of chart types  1805 , selection of axis data  1807 , etc. are further available more advanced capabilities. 
     For example, when the user chooses to analyze the sentiment with regards to his product according to gender  1801 , with respect to all age groups (combined)  1803 , he may be presented a bar chart  1810  depicting the positive vs. negative vs. natural attitudes towards his produce. 
     Reference is now made to  FIG. 19  which is a flow diagram of an exemplary method for analyzing attitudes expressed in web sites, according to a preferred embodiment of the present invention. 
     According to a preferred embodiment, attitude data  1900  relating to a subject which is predetermined by a user, say using the apparatus  1000 , is collected  1901  from pre-selected web site(s), say by a collector  110 , as described hereinabove. 
     The pre-selected web sites may include, but are not limited to: Chat sites, Interactive news groups, Discussion groups, Forums, blogs and the like where people express their views and feelings. For example: Internet uses may express their views regarding a proposed tax reform, to be discussed by a government, regarding a new product etc. 
     Optionally, the collecting may include any number of web sites. 
     Next, the collected attitude-data is processed  1903 , say by a processor as described hereinabove. 
     The processing  1903  of the attitude-data may typically include content analysis techniques, data mining, and other data analysis techniques. These techniques may implement any one a variety of algorithms, which includes but is not limited to: neuronal networks, rule reduction, decision trees, pattern analysis, text and linguistic analysis techniques, or any relevant known in the art algorithm. Detailed exemplary algorithms, usable for processing of the attitude-data are provided herein below. 
     Finally, the processed attitude-data is used for outputting  1905  attitude-information to a user, say by an outputter  130 , as described hereinabove. 
     The outputting  1905  may be carried out utilizing graphical tools for presenting and analyzing attitude-information, as described in greater detail hereinabove. 
     According to a preferred embodiment of the present invention, the collecting  1901  may include crawling the web sites according to a predefined policy. Preferably, the collecting further includes parsing relevant downloaded pages of the pre-selected web sites, as described in greater detail hereinabove. 
     Preferably, the crawling is carried out according to a policy defined by a user, say by a collecting policy definer  160 , as described hereinabove. 
     According to a preferred embodiment the processing  1903  is carried out in an initial pre-processing step, where metadata relating to the collected attitude-data is processed in advance. 
     According to a preferred embodiment, the processing  1903  includes categorizing relevant text of the collected attitude-date using supervised approaches. 
     Preferably, in addition to classical text categorization by content, which involves assigning each message/document a list of topics being discussed in it, a preferred embodiment may include using text categorization by style technologies. Such technologies may add and categorize vital data about the document author, like his age or his/her gender, without having any direct background knowledge about the author. 
     As described herein above, categorization by style technologies are based on the idea of analyzing the writing style, the language used by the author, the use of foreign language words etc. to indirectly learn about the author. 
     Style text categorization may enrich the queries and analysis the end user can perform on the data. Since this style derived information is static, it can be generated in a metadata pre-processing stage. 
     Reference is now made to  FIG. 20  which is a flow diagram of an exemplary method for categorizing attitude-data text according to a preferred embodiment of the present invention. 
     The general flow of the exemplary categorization process includes: data manipulation  2001 , and then feature selection  2003  and feature reduction  2005 , applied, as described in greater detail hereinabove, for yielding a feature set/cluster  2010 . The example further includes train\test  2015  procedures for forming a model which best represents the attitude-information in the collected attitude-data. 
     Data Manipulation 
     Texts cannot be directly interpreted by a classification system. Because of this, an indexing procedure that maps a text into a compact representation of its content is preferably uniformly applied to training, validation, and testing of messages/documents, for successfully carrying out the categorization and mining of the attitude data. 
     The choice of a representation for text depends on what one regards as the meaningful units of text (the problem of lexical semantics) and the meaningful natural language rules for the combination of these units. Similarly to what happens in IR (Information Retrieval), in TC (Text Categorization) a text may be represented as a vector of pairs of terms and their weights. Each of the document terms (sometimes called features) occur at least once (in at least one message/document). There are different ways to understand what a term is and different ways to compute term weights. 
     A typical way for understanding a term is to identify the term using a word. The way is often referred to as either the set of words or the bag of words approach to document representation, because a bag or set of words is available from which to select the meaning of the term. With the bag of word approach, a list of words and word combinations is weighted according to the number of appearances of each word or word combination in the document. Predefined stop words/combinations are then excluded from the list, and the term is understood in light of the weights of the remaining words/combinations. 
     Feature Selection 
     Feature selection may relate to various types of features ranging from textual ones, like words, dictionary based words and also some more grammatical features like part-of-speech tags and their combination. Preferably, Feature selection further includes combinations of phrases, represented as N-grams. N-grams are phrases combining a number (n) of words. 
     Feature Filtering 
     Unlike in text retrieval, in TC the high dimensionality of the term space may be problematic, as the objective of TC is to extract an attitude from a mass of words rather than to search for a given phrase. In fact, while typical algorithms used in text retrieval can scale up to high values of terms, the same does not hold of many sophisticated learning algorithms used for TC which is about extracting the general attitude rather then its detailed expression. 
     Preferably, because of this problem, a Feature filter is also implemented. The effect of the filtering is to reduce the size of the term space. The filtering may apply methods for feature reduction that include but are not limited to: dictionary based reduction, term frequency reduction, and information-gain filtering. 
     With dictionary based reduction, a limitation is made to a certain group of words that appears in a predefined dictionary words list (like function words). 
     Term frequency reduction is based on filtering out features that appear in too many messages/documents, such as “I” and “The”, or in too few messages/documents. That is to say, terms that appear in too many messages are regarded as too general whereas terms that appear in too few messages are regarded as too specific. Information gain filtering measures the decrease in entropy as a result of the presence of a certain term in the text. This is useful to identify the features that are best distinguishing between groups in the space of documents/messages. 
     For example, entropy may be formally defined as: 
                     IG   ⁡     (   t   )       =       ⁢         ∑   1             ⁢   m       ⁢     P   ⁢     (     C             ⁢   i       )     ⁢   log   ⁢           ⁢   P   ⁢     (     C             ⁢   i       )         +                     ⁢       P   ⁢       (   t   )     ·     [       ∑   1             ⁢   m       ⁢     P   ⁢     (       C             ⁢   i       |   t     )     ⁢   log   ⁢           ⁢   P   ⁢     (       C             ⁢   i       |   t     )         ]         +                     ⁢     P   ⁢       (     t             ⁢   _       )     ·     [       ∑   1             ⁢   m       ⁢     P   ⁢     (       C             ⁢   i       |     t             ⁢   _         )     ⁢   log   ⁢           ⁢   P   ⁢     (       C             ⁢   i       |     t             ⁢   _         )         ]                     
Where:
     C denotes a category.   
     
       
         
           
             
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     Train\Test Procedure 
     Preferably, one or more machine learning algorithms is applied on the data set to find a model which best extracts attitude data from the messages/document downloaded from the crawled web sites. 
     For example, given a collection of messages/documents discussing “sports” and “non-sports”, the model learns how to distinguish sport messages/documents from non-sport ones. 
     In order to do this several models of text categorization may be applied in including but not limited to: Decision Tree (J48), Naïve Bayes, and SVM. 
     Decision Tree—a decision tree (DT) for text categorization is a tree in which internal nodes are labeled by terms, branches departing from them are labeled by the weight that the term has in the test document, and leafs are labeled by categories. 
     Such a tree categorizes a test document by recursively testing the weights that the terms labeling the internal nodes have in a vector, until a leaf node is reached. The label of this node is then assigned to the document. Most such trees use binary document representations, and are thus binary trees. 
     There are a number of standard packages for DT learning, and most DT approaches to TC have made use of such packages. Among the most popular ones are ID3 (used by Fuhr et al. [1991]), C4.5 (used by Cohen and Hirsh [1998], Cohen and Singer [1999], Joachims [1998], and Lewis and Catlett [1994]), and C5 (used by Li and Jain [1998]). 
     Naïve Bayes—Let X be the data record (case) whose class label is unknown. Let H be some hypothesis, such as “data record X belongs to a specified class C.” For classification, we want to determine P (H|X)—the probability that the hypothesis H holds, given the observed data record X. 
     P (H|X) is the posterior probability of H conditioned on X. For example, the probability that a fruit is an apple, given the condition that it is red and round. In contrast, P(H) is the prior probability, or a priori probability, of H. 
     In this example P(H) is the probability that any given data record is an apple, regardless of how the data record looks. The posterior probability, P (H|X), is based on more information (such as background knowledge) than the prior probability, P(H), which is independent of X. 
     Similarly, P (X|H) is posterior probability of X conditioned on H. That is to say, it is the probability that X is red and round given that we know that it is true that X is an apple. P(X) is the prior probability of X, i.e. it is the probability that a data record from our set of fruits is red and round. 
     Bayes theorem is useful in that it provides a way of calculating the posterior probability, P(H|X), from P(H), P(X), and P(X|H). Bayes theorem may be formally defined by the equation:
 
 P ( H|X )= P ( X|H ) P ( H )/ P ( X ).
 
     SVM—The support vector machine (SVM) method has been introduced in TC by Joachims [1998, 1999] and subsequently used by Drucker et al. [1999], Dumais et al. [1998], Dumais and Chen [2000], Klinkenberg and Joachims [2000], Taira and Haruno [1999], and Yang and Liu [1999]. 
     In geometrical terms, it may be seen as an attempt to find, among all the surfaces  — 1,  — 2, : : : in j. T j-dimensional space that separate the positive from the negative training examples (decision surfaces), the _i that separates the positives from the negatives by the widest possible margin. That is to say, such that the separation property is invariant with respect to the widest possible translation of _i. 
     This idea is best understood in a case where the positives and the negatives are linearly separable, in which the decision surfaces are (jT j−1)-hyper planes. 
     The SVM method chooses the middle element from the “widest” set of parallel lines, that is to say, from the set in which the maximum distance between two elements in the set is highest. It is noteworthy that this “best” decision surface is determined by only a small set of training examples, called the support vectors. The method described is applicable also to a case where the positives and the negatives are not linearly separable. 
     As argued by Joachims [1998], SVM offers two important advantages for TC: One being that term selection is often not needed, as SVM tends to resistant to overfitting—that is to producing a too complex statistical model compared with the amount of data, and can handle large dimensionality, and the other being that no human and computer processing effort in parameter tuning on a validation set is needed, as there is a theoretically motivated default choice of parameter settings which has also been shown to provide the best effectiveness. 
     The above described methods and algorithms are usually implemented in an on-line supervised manner, involving an analyst/user. A preferred embodiment of the present invention further implements unsupervised approaches. Preferably the unsupervised approaches facilitate processing relatively large volumes of textual attitude-data. 
     A preferred embodiment of the present invention involves unsupervised approaches that are based on data mining techniques. 
     A preferred embodiment of the present invention may utilize a two layers approach. One layer is an application layer and the other is an open query layer where the user may define relevant queries. 
     The application layer may use, but is not limited to using: 
     Data representation—a data representation component may be used for internally representing text of the attitude-data. 
     Memory and performance efficient data-structures are essential for performing the complex online analysis tasks. The data representation component translates the text to a compact binary representation, enabling faster analysis, for example using following steps. 
     Frequency analysis—a frequency analyzer may be used to provide the user with various statistics on different parameters, like: most frequent words, phrases, number of authors, unique authors, or distribution over time frame. The frequency analyzer may utilize a counter for counting words, phrases, etc. The counter provides raw data that is then processed by the frequency analyzer, to generate various statistics data. 
     Concept Analysis—a concept analyzer may be employed for finding the most interesting and relevant phrases relating to a certain concept, in the attitude-data. 
     The analysis handles single word phrases as well as relevant multiple word phrases. The concept analyzer may scan all the words or phrases in the collection, and assign a relevance score to each of them, to indicate relevance of the word or phrase to the researched concept. 
     Preferably, the relevance is measured by the ratio between a frequency for the word/phrase for co-occurring with a “leading concept/word” (i.e. the concept/word currently being analyzed) to the frequency of the co-occurrence not with the “leading concept/word”. The higher this ratio is, the more relevant is this word/phrase. 
     In order to extract phrases (longer than one word), the analysis may include examining the top K (usually 100) words, and then look for phrases containing at least one of the top K words. Those phrases whose relevance score (as being calculated for single words) is higher than a certain threshold are considered relevant. 
     Correlator measurement—according to a preferred embodiment, a correlation measurer may be used to reveal interesting relationships between phrases and concepts in the attitude-data. 
     When trying to analyze a concept, one of the important information is what is mentioned\related to this concept, and how these are issue-related. This is done by measuring correlation. 
     According to a preferred embodiment of the present invention, the relevant phrases that were identified in the concept analysis stage are populated in a matrix where the distances between all the pair of phrases are calculated, as described ion greater detail herein below. 
     Then, the matrix may be populated into a visual interface, with the analyzed concept/phrase in the middle, and the relevant phrases surrounding it, as illustrated in  FIG. 14  and discussed hereinabove. 
     The distance from the central concept measures the relevance to it, and the distances among the other phrases themselves represents their closeness. These metrics are directly derived from the distances in the distance matrix, populated as described below. 
     Preferably, in order to calculate the distance between two phrases, two parameters are taken into consideration: the significance of the co-occurrence of these phrases and the frequency of this occurrence. 
     According to a preferred embodiment, the distance between phrases a and b is calculated according to the formula: 
     
       
         
           
             
               
                 
                     
                 
               
             
             
               
                 
                   
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     freq(a,b)=Frequency for a to co-appear with b, for some measure of togetherness 
     freq(a,{tilde over (b)})=Frequency for a to appear where b does not appear 
     Note that D(a,b) is not symmetric with D(b,a). 
     In a preferred embodiment, a distance between the two phrases, as put in the matrix, is the maximum of the two:
 
 DV ( a,b )=Max( D ( a,b ), D ( b,a ))
 
     Quotation extraction—a quotation extractor is preferably employed for extracting key quotations from a data file that contains a given list of concepts, in order to provide a user with the relevant text citations best describing a relationship, existing in the attitude-data between a concept and its neighbor (relevant) phrases. 
     The challenge in the above case is identifying ad-hoc the most relevant documents, finding in them, the most relevant phrases and then displaying the phrases to the end user. The relevance in this case is measured by the frequency of the searched phrases in the text, in coordination with their distance in the message/document itself. 
     Clustering—according to a preferred embodiment, the concepts relating to the attitude-data may be clustered, say by a clusterer, as discussed hereinabove. 
     Clustering may include aimed clustering which includes clustering the concepts that strongly relate to a given topic. Clustering may also include free clustering where a given attitude-data set is clustered into distinctive groups which strongly relate to one another. This functionality is useful when analyzing new domains where the analyst doesn&#39;t have any prior knowledge on it. 
     Reference is now made to  FIG. 21  which is an exemplary pseudo-code algorithm for clustering concepts relating to attitude-data, according to a preferred embodiment of the present invention. 
     Free clustering may be implemented using a clustering algorithm as exemplified using  FIG. 21 , to provide the user with the list of most relevant document clusters in the collection, along with cluster names and list (and view) of the documents belonging to each cluster. 
     The algorithm of  FIG. 21  has the following advantages over the classical clustering algorithms: no predefined fixed number of clusters as in the classical clustering algorithms, ability to control the words that build the different clusters, and ability to merge and split clusters. 
     A general well known problem of traditional clustering algorithms pertains to relevance of the generated clusters to needs of the end-user, and that the traditional algorithms are based on the end-user&#39;s previous knowledge of well known world facts. 
     The example algorithm enables the user to control the output and quality of the final clusters, thus overcoming these shortcomings. 
     According to a preferred embodiment of the present invention, the processing of the attitude-data further includes data mining techniques. 
     Preferably, the data mining techniques may include, but are not limited to Pattern analysis and Trend analysis. 
     With Pattern analysis the processing includes searching for patterns in the statistics that may be provided by a statistics generator as described hereinabove. 
     The process may reveal relationships that are not obvious or sift out meaningful data from noise, exploiting favorable patterns and avoiding bad ones. Pattern analysis is a traditional part of data mining algorithms as applied on data stored in relational databases. However, in a preferred embodiment, Pattern analysis is further applied to unstructured textual data. 
     With Trend analysis, the processing further includes detecting emerging trends in the attitude-data, like new emerging products, consumer habits and more. 
     Optionally, trend analysis may be done by applying linear regression principles on the data set results. Once a list of related phrases is discovered, an analysis of correlation trends over time using linear regression is carried out 
     If a strong positive (or negative) correlation trend (by having a high absolute value of the correlation derivative) is discovered, it is checked for consistency over time, by measuring the mean squared error. 
     The phrases that have the strongest trend derivative, and the least error, are regarded as those with the higher trends, and are displayed to the user along with their trend graph, and regression equation. 
     Platform Architecture 
     Reference is now made to  FIG. 22  which is a simplified block diagram of an exemplary architecture of an apparatus for analyzing attitudes expressed in web sites, according to a preferred embodiment of the present invention. 
     An architecture according to a preferred embodiment may be a distributed environment architecture having loosely coupled components  2221 - 5 , communicating through one central fault tolerant management and data center  2230 . 
     High availability of the data center  2230  is ensured by running the data center in a computer server cluster with redundant machines. 
     The central data center  2230  preferably runs on top of a central data storage (data base/data warehouse)  2235 , secured with redundant machines ensuring high-availability. The data-center  2230  stores the current system status and configuration (along with data to be analyzed) as well as the communication messages between the various system components. 
     Having a message based communication system enables full distribution of the various run time components, thus having full scaling capability. This architecture also enables real time configuration changes, affecting immediately all the running components without requiring a restart of the whole system or waiting for long update time. 
     Preferably, all the components communicate in an asynchronous mode, using messages. All the messages are posed to queues waiting for processing by each of the components. Each component owns one input message queue, one output queue and one management (commands) queue. The input queue contains the processing requests waiting for a component to be processed, upon completion, the processed document is posted to an output queue (which is actually the input for the next component in the pipeline). 
     An apparatus according to a preferred embodiment of the present invention may provide means for proper storage for any volume of data with fast access capabilities. 
     It is expected that during the life of this patent many relevant devices and systems will be developed and the scope of the terms herein, particularly of the terms “Collector”, “Processor”, “Outputter”, “Database” and “data Warehouse”, is intended to include all such new technologies a priori. 
     Additional objects, advantages, and novel features of the present invention will become apparent to one ordinarily skilled in the art upon examination of the following examples, which are not intended to be limiting. Additionally, each of the various embodiments and aspects of the present invention as delineated hereinabove and as claimed in the claims section below finds experimental support in the following examples. 
     It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination. 
     Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims. All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention.