Patent Publication Number: US-6665679-B2

Title: Method and system for symbolical linkage and intelligent categorization of information

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. application Ser. No. 09/336,031, filed Jun. 18, 1999. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to the area of electronic storage and retrieval of information. In particular, the present invention pertains to a method and system for referencing, storing, retrieving and intelligently categorizing symbolically linked information. 
     BACKGROUND INFORMATION 
     Many types of information are referenced and archived in everyday life using a symbolic code. Typically a symbolic code is employed by a community of users who require a consistent and convenient language to refer to a particular set of signified objects—entities in the real world signified by the symbols of the code. However, in fact, most symbolic codes are not formalized and therefore users do not employ these codes in a coordinated and consistent manner. Thus, interpretation of symbols is problematic. 
     For example, in the financial world, financial exchanges each use a different set of exchange (ticker) symbols to refer to companies and their securities. Although within the United States, local exchanges coordinate symbol names, in general, worldwide exchanges each use a particular symbol set and symbol structure for identifying companies and their securities. For example, both the PSE (Pacific Stock Exchange) and the NYSE (New York Stock Exchange) use the symbol ‘IBM’ to signify a security of IBM. However, in the United States the symbol ‘T’ refers to an AT&amp;T security while in Canada ‘T’ refers to a security of the company Telos. In Britain the symbol ‘T’ may refer to the security of a different company. 
     Vendors of financial information such as Reuters, Bloomberg, Bridge, etc. also employ unique symbol sets and structures to refer to companies and their securities. Many vendors of financial information use a structured symbol code segmented into two portions separated by a delimiter character. For example, a vendor may use the symbol structure ROOT[delimiter character]SOURCE where the ROOT segment refers to a particular company&#39;s security and the SOURCE segment refers to a country or exchange where that security is traded. The delimiter character is typically a character such as ‘@’ or ‘.’. 
     Because of the multiplicity of symbols sets in circulation, interpreting a symbol in order to identify a security and a company it belongs to is problematic. For example, a single vendor may use the symbol ‘IBM.FR’ to refer to an IBM security traded in France and ‘IBM.GB’ to refer to the same IBM security traded in Great Britain. In either case, both symbols IBM.GB and IBM.FR are associated with the same company IBM. However, two vendors may use the same root and source segments to refer to two different securities issued by two different companies. For example, a first vendor might use the symbol ‘T.U.S.’ to refer to an AT&amp;T security traded in the United States while a second vendor might employ the symbol ‘T@US’ to refer to a security of a different company. On the other hand, two different vendors may use different root and source symbols to refer to the same security of a company. For example, a first vendor might use the symbol ‘IBM.UK’ to refer to an IBM security traded in Great Britain while a second vendor may use the symbol ‘IB.EG’ to refer to the same IBM security. 
     The need for a consistent system to reference information linked to particular companies has grown even more important as online financial research has increased. Document repositories storing financial documents are accessible to investors and researchers via public networks such as the Internet or private networks. Contributors may submit research documents related to particular companies or securities to a document repository for archival and clients (i.e., investors or researchers) of the document repository may retrieve documents related to particular companies or securities of interest. 
     In the archival process, contributors typically submit a document along with an input string that refers to the company or security that is the subject of the submitted document. However, because of the multiplicity of symbol sets in use, accurate archival and retrieval of documents is highly problematic. Contributors will typically submit an input string using any of the various vendor symbols and exchange symbols in circulation or possibly may use an idiosyncratic symbol unique to that contributor. Thus, identifying a company security referred to by a contributor is difficult. Similarly, clients desiring to retrieve documents regarding a particular company will submit input symbols in a variety of formats including vendor symbols, exchange symbols or an isolated root symbol, which complicates the retrieval process. 
     The difficulties regarding the interpretation of security symbols illustrate a general need for a consistent and unambiguous system for referencing symbolically linked information so that the information may be accurately archived and retrieved. 
     Furthermore, the financial documents produced by these financial companies vary in type and topic. Some financial documents may emphasize a particular subject matter such as commodities, equity reports, industry reports, portfolio/asset strategies, derivatives, and/or foreign exchange/currencies. A particular company may produce documents predominantly related to a certain subject matter such as fund research or commodities. It would be advantageous for documents which emphasize a common topic to be readily retrievable. The authors of various financial documents use different research methodologies in order to produce the financial document such as fundamental, technical, quantitative or strategic research techniques. The methodology used by a person may affect the style, tone and conclusion of the financial document, therefore a person reviewing the financial document may want to know this information prior to reading the financial document. Also, financial companies may have various reasons for generating a financial document such as general commentary, forecasting, news reports and/or market data. Since financial documents may cover various topical subjects, are derived by using various research techniques and are produce for various purposes all which affect content, therefore a method of document archival and retrieval based upon these various criteria would be advantageous. 
     SUMMARY OF THE INVENTION 
     The present invention provides a method and system for the reference, archival and retrieval of symbolically linked information and the intelligent categorization of the information based upon subject matter, research methodology, publication purposes and primary subject matter. A master symbol database stores a plurality of master symbols, wherein each master symbol is formatted according to a predetermined structure. Each master symbol in the master symbol database is linked to a parent identifier that identifies a unique object. A categorical symbol database stores a plurality of categorical symbols which are also formatted according to a predetermined structure. The categorical symbol is linked to a unique document identifier that enables the retrieval of a document based upon its categorical assignment. Users may archive or retrieve symbolically linked information in an information database by providing an input symbol. The input symbol is normalized and the master symbol database is searched to find a matching master symbol. The parent identifier linked to the matching master symbol is then used to retrieve or archive information in the information database. If the input symbol includes a categorical symbol, then the categorical symbol database is searched to find a matching categorical symbol which is used to categorically retrieve or archive the information in the information database. 
     According to one embodiment, the present invention is applied in the context of a computer based document repository in which automatic archival of documents submitted by contributors and automatic retrieval of documents requested by clients is provided based upon analysis of an input symbol. The document repository stores a database of master symbols and linked parent identifiers referencing a plurality of objects or sub-objects. The document repository also stores a database of categorical symbols that are used to intelligently categorize the documents within the database. In the archival process, the document repository electronically receives a contributor submitted document and an input symbol pertaining to an object referenced in the document. The input symbol is normalized and used to search the master symbol database to find a matching master symbol. The document is then stored in a document database so that it is linked to the parent identifier corresponding to the matching master symbol. In regard to the categorical archival, the input symbol is used to search the categorical symbol database to find a matching categorical symbol. The document is then stored in a document database where the document identifier is linked to the matching categorical symbol. If the normalized symbol is not found in the master symbol database nor is it found in the categorical symbol database, an analysis of the contributor&#39;s historical patterns is performed to attempt to resolve the indeterminacy. Clients may retrieve documents stored in the repository by electronically providing an input symbol. The input symbol is normalized and at least one client preference parameter may be used to resolve any indeterminacy in the input symbol. The normalized symbol is used to search the master symbol database in order to find a matching master symbol. The parent identifier linked to the matching master symbol is then used to retrieve documents linked to the parent identifier. The normalized symbol is also used to search the categorical symbol database in order to find a matching categorical symbol. The matching categorical symbol is then linked to the document identifier in order to retrieve documents with the appropriate categorical symbol. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 a  depicts a relationship between a parent identifier, a number of master symbols linked to the parent identifier, an object and a number of sub-objects associated with the object according to one embodiment of the present invention. 
     FIG. 1 b  shows master symbols linked to a plurality of parent identifiers according to one embodiment of the present invention. 
     FIG. 1 c  depicts a symbol template according to one embodiment of the present invention. 
     FIG. 1 d  depicts a particular example of a symbol template according to one embodiment of the present invention. 
     FIG. 1 e  depicts another a particular example of a symbol template according to one embodiment of the present invention. 
     FIG. 2 is a flowchart depicting a set of steps for interpreting an input symbol in order to identify a unique associated object and any categorical symbol within the input symbol according to one embodiment of the present invention. 
     FIG. 3 is a block diagram depicting a network architecture that allows the electronic archival and retrieval of symbolically linked documents according to one embodiment of the present invention. 
     FIG. 4 is a block diagram depicting the architecture of a portion of a document repository system for archiving and retrieving symbolically linked documents according to one embodiment of the present invention. 
     FIG. 5 a  depicts a data structure for storage of master symbol data in a master symbol database according to one embodiment of the present invention. 
     FIG. 5 b  depicts a particular example of the data structure shown in FIG. 5 a  applied in the context of storage of company security symbols traded throughout the world according to one embodiment of the present invention. 
     FIG. 6 depicts a data structure for the storage of documents in a document file database according to one embodiment of the present invention. 
     FIG. 7 depicts a data structure used in a relational database for storing information relating to documents stored at a document repository according to one embodiment of the present invention. 
     FIG. 8 depicts a data structure used in contributor historical pattern database for storing information relating to historical symbol use trends of particular contributors according to one embodiment of the present invention. 
     FIG. 9 depicts a data structure used in a client database for storing information relating to client preferences according to one embodiment of the present invention. 
     FIG. 10 depicts a data structure used in a normalization table database relating to various symbol sets according to one embodiment of the present invention. 
     FIG. 11 depicts a data structure used in an object database for storing information relating an object to a parent identifier according to one embodiment of the present invention. 
     FIG. 12 is a flowchart of steps for the creation of a master symbol database according to one embodiment of the present invention. 
     FIG. 13 is a block diagram depicting information flow between various servers and databases at document repository  319  relating to the automatic archival of documents received from a contributor according to one embodiment of the present invention. 
     FIG. 14 is a flowchart of steps for the automatic archival of a document at a document repository according to one embodiment of the present invention. 
     FIG. 15 is a block diagram depicting information flow between various servers and databases at document repository  319  relating to the automatic retrieval of documents based upon an input symbol provided by a client  305  according to one embodiment of the present invention. 
     FIG. 16 is a flowchart of steps for the automatic retrieval of documents at a document repository based upon a client submitted input symbol according to one embodiment of the present invention. 
     FIG. 17 is a flowchart depicting a set of steps for generating a contributor historical database according to one embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION 
     The present invention provides a method and system for the reference, archival and retrieval of symbolically linked information and the intelligent categorization of the information based upon subject matter, research methodology and publication purposes. The embodiments described herein pertain to a computer based document repository system for referencing, archiving and retrieving documents. According to one embodiment, the document repository stores documents relating to companies traded throughout the world. However, the embodiments described herein are merely illustrative and not intended to limit the scope of the claims appended hereto. The present invention is applicable to any environment where it is necessary to archive, retrieve or reference symbolically linked information and to intelligently categorize the symbolically linked information. 
     FIG. 1 a  depicts a relationship between a parent identifier, a number of master symbols linked to the parent identifier, an object and a number of sub-objects associated with the object according to one embodiment of the present invention. The bottom portion of FIG. 1 a  shows an exemplary object  130  and a number of sub-objects  140   a - 140   b  associated with object  130 . FIG. 1 a  also depicts object space  150 , which consists of all possible objects. For example, according to one embodiment, object space  150  includes all companies traded throughout the world, object  130  represents a particular company and associated sub-objects (e.g.,  140   a - 140   c ) represent securities issued by that company. 
     The top portion of FIG. 1 a  depicts the structure of a master symbol database for representing objects  130  and sub-objects  140   a - 140   c . In particular, parent identifier  110  refers to object  130  and master symbols  115   a - 115   c  refer to sub-objects  140   a - 140   c  respectively. Note that the top and bottom portions of FIG. 1 a  are roughly symmetric. As depicted in FIG. 1 a , each master symbol (e.g.,  115   a - 115   c ) is linked to a parent identifier  110 . Each parent identifier  110  in turn, refers to a unique object existing in object space  150 . 
     The function of a master symbol database is to allow the identification of a particular object based upon an input symbol. This is indicated in FIG. 1 a  by the intersection of three planes in object space  150 . As described in detail below, an input symbol is normalized and the master symbol database is searched to find a matching master symbol. The parent identifier linked to the matching master symbol is used to identify an object  130 . 
     Although FIG. 1 a  depicts a single parent identifier  110  and only three master symbols  115   a - 115   c , a master symbol database typically will contain many master symbols, wherein each master symbol is linked to one of a plurality of parent identifiers  110 . For example, FIG. 1 b  shows master symbols  115   a - 115   c  linked to parent identifier  110   a , master symbols  115   d - 115   f  linked to parent identifier  110   b , master symbols  11   fg - 115   k  linked to parent identifier  110   c  and master symbols  115   l - 115   m  linked to parent identifier  110   d . Thus, master symbols  115   a - 115   c  are associated with a first object, master symbols  115   d - 115   f  are associated with a second object, master symbols  115   f - 115   k  are associated with a third object and master symbols  115   l - 115   m  are associated with a fourth object. 
     An example will further illustrate the application of the scheme depicted in FIG. 1 a . According to one embodiment, each object  130  represents a company and each sub-object (e.g.,  140   a - 140   c ) represents a particular security issued by that company. According to this example, a unique parent identifier  110  is assigned to each company. Each security issued by a particular company is assigned a unique master symbol, which is linked to the parent identifier  110  assigned to the company that issues the security. Each master symbol is stored in the master symbol database along with the linked parent identifier  110 . 
     According to one embodiment, all master symbols stored in a master symbol database utilize a pre-defined structure, which is defined by a symbol template. FIG. 1 c  depicts a symbol template according to one embodiment of the present invention. Symbol template  145  consists of an arbitrary number of symbol fields  150 ( 1 )- 150 (N). Each symbol field  150 ( 1 )- 150 (N) represents an information category and corresponds to a particular attribute of the symbolized objects or sub-objects. Thus, all master symbols stored in a master symbol database will be structured according to the same pre-determined symbol template  145 . 
     In particular, each master symbol stored in a master symbol database will contain a master symbol segment corresponding to a portion of the symbol fields  150 ( 1 )- 150 (N) defined by the symbol template  145 . Each symbol segment comprises a text string. For example, for a symbol field pertaining to a country attribute, symbols stored in a master symbol database may include the symbol segments (i.e., text strings) ‘US’, ‘GB’ and ‘FR’ to refer to the United States, Great Britain and France respectively. For example, FIG. 1 a  shows master symbols  115   a - 115   c  structured according to a symbol template  145  containing three symbol fields (not shown). This is evident from the fact that each master symbol  115   a - 115   c  is comprised of three symbol segments (i.e.,  120   a   1 - 120   c   1 ,  120   a   2 - 120   c   2  and  120   c   1 - 120   c   3 ), corresponding respectively to the symbol fields defined by the symbol template. 
     An example will further illustrate the relationship of a symbol template  145  to the corresponding symbol segments forming the structure of a symbol stored in a master symbol database. According to one embodiment, master symbols stored in the master symbol database symbolize company securities traded in a particular market. In this case, a symbol template  145  such as that shown in FIG. 1 d  may be used. The first symbol field  150   a , referred to as a root field, specifies a security of a company and the second symbol field  150   b , referred to as a source field, specifies a country where that security is traded. Thus, in this case all symbols stored in the master symbol database will contain two symbol segments, a root segment (i.e., an ASCII string corresponding to a company security name) and a source segment (i.e., an ASCII string corresponding to a country where the security is traded), corresponding respectively to symbol fields  150   a  and  150   b  defined by symbol template  145  shown in FIG. 1 d.    
     Another exemplary embodiment of the symbol template  145  is shown in FIG. 1 e , which enables the intelligent categorization of the symbolically linked information. As shown in FIG. 1 d , the first symbol field  150   a  is referred to as the root field which specifies a security of a company and the second symbol field  150   b  is referred to as the source field which specifies a country where that security is traded. FIG. 1 e  includes a third symbol field  150   c  which is referred to as the categorical symbol field which identifies the proper category to be linked and stored in the categorical symbol database. The symbol field  150   c  allows the archival and retrieval of symbolically linked information based on categorical segments found in the categorized symbol database. 
     Master symbols stored in a master symbol database are stored in a normalized format to provide a consistent method for referencing and searching the master symbol database. Similarly, categorical symbols are stored in a categorical symbol database are also stored in a normalized format to provide a consistent method for referencing and searching the categorical symbol database. Thus, for example, the symbol segment ‘US’ may be used for all master symbols stored in a master symbol database to refer to the United States. Also, the symbol segment “CR” may be used as a categorical symbol stored in the categorical symbol database in order to create a category of commodity research related information. 
     Although FIG. 1 a  depicts an example in which the master symbols stored in the master symbol database refer to sub-objects  140   a - 140   c , in an alternative embodiment the master symbols  140   a - 140   c  refer to object  130  itself. The structure of a master symbol database and a process for linking symbols to a parent identifier is described in more detail below. 
     Users of a document repository may submit an input symbol to be searched against a master symbol database in order to either store or retrieve information associated with the input symbol. However, because symbol usage is idiosyncratic, an input symbol must be normalized and interpreted so that an object  130  it is associated with can be identified. FIG. 2 is a flowchart depicting a set of steps for interpreting an input symbol in order to identify a unique associated object according to one embodiment of the present invention. In step  210 , an input symbol is received from a user. In step  220 , the input symbol is processed to obtain a normalized symbol according to a set of normalization rules. A procedure for the normalization of input symbols is described in more detail below. In step  230 , it is determined whether the normalized symbol is known (i.e., it can be matched to a master symbol stored in a master symbol database). If the normalized symbol is known, the parent identifier  110  linked to the normalized symbol is retrieved. Then, in step  250 , using the retrieved parent identifier  110 , appropriate processing such as retrieval or archival of information (for example, an electronic document) is performed. In addition to identifying the parent identifier, the symbol input may include a categorical symbol, step  225 . If a categorical symbol is included in the symbol input, then performance of the appropriate categorical retrieval or archival process is performed, step  235  and the input symbol identification is complete. The procedure ends in step  290 . 
     If the normalized symbol  115  is not known, i.e., it cannot be matched to a master symbol stored in a master symbol database (‘no’ branch of step  230 ), an analysis of historical patterns of the submitter of the symbol is performed in step  260 . As discussed in more detail below, this may involve searching a separate database to determine whether the unknown input symbol was ever used before by the user and how it was interpreted. Or, in the alternative, if a particular symbol segment cannot be resolved, statistical analysis of the user&#39;s history may be performed to determine the frequency of occurrence for any unresolved symbol segments. If it is possible to resolve the symbol using historical patterns of the contributor of the symbol, the symbol is resolved (‘yes’ branch of step  270 ) and flow continues with the retrieval of the parent identifier  110  linked to the normalized symbol (step  240 ). If not (‘no’ branch of step  270 ), the procedure fails (step  280 ). Also, user historic categorical pattern data may be used to achieve the categorical retrieval or archival process. If no categorical symbols are included in the symbol input, then the user&#39;s historical categorical patterns may be analyzed in order to properly perform a categorical retrieval or archive. If a reasonable interpretation of the user categorical historical patterns is possible then the categorical retrieval or archival process is completed in step  235 , otherwise the categorical retrieval or archive fails, step  280 . 
     FIG. 3 is a block diagram depicting a network architecture that allows the electronic archival and retrieval of symbolically linked documents according to one embodiment of the present invention. Document repository  319  contains, among other components, contributor gateway server  340   a  and client gateway server  340   b . Servers  340   a  and  340   b  each include a processor and memory for executing program instructions as well as a network interface (not shown). 
     According to one embodiment, client  305  uses personal computer  310  running browser software (not shown) to communicate with document repository  319  via modem  315 , POTS telephone line  317 , Internet service provider  320 , T 1  line  330   d , Internet  340 , T 1  line  330   c  and client gateway server  340   b . Client  305  may search for particular data or documents stored at document repository  319  by submitting an input symbol relating to a desired object or sub-object. Client gateway server  340   b  runs a number of processes (described in more detail below) for performing search and retrieval of documents from document repository  319 . In particular, client gateway server  340   b  runs a number of processes for receiving an input symbol from a client  305 , normalizing the input symbol, searching the master symbol database  420  to find a corresponding parent identifier (if it exists), and retrieving documents from document database linked to that parent identifier. Also, the client gateway server  340   b  may search the document repository  319  in order to retrieve or archive documents based upon a categorical symbol that may be a portion of the input symbol. The documents which have been assigned, by a user or using the historical pattern associated with the user, a categorical symbol may be retrieved or archived based upon the categorical symbol. The categorical symbols associated with the documents are stored in the categorical symbol database  425 , and are linked to the document file database  450  via the contributor gateway server  340   a  and the client gateway server  340   b.    
     Client gateway server  340   b  also runs a process to provide a GUI (Graphical User Interface) that provides a convenient interface for clients  305  to submit input symbols for searching document repository  319  for specific documents and for displaying retrieved documents to the client. According to one embodiment client gateway server  340   b  serves HTML (Hypertext Markup Language) content located on a storage device (not shown) to clients (e.g.,  305 ) connecting to client gateway server  340   b . In particular, HTML pages stored on client gateway server  340   b  provide a convenient user interface that allows clients to enter input strings to search document repository  319  for documents relating to a particular object symbolized by an input symbol. Also, clients may search the document repository  319  for documents grouped into particular categories based upon categorical symbols within the input symbol. The categorical search may include a search for a particular type of document, i.e. commodity research, derivative research, and industry reports, associated with a particular company or perhaps published in a particular country. Another exemplary embodiment of the GUI may provide a convenient interface for clients to include a categorical identifier for the input symbol. In addition, client gateway server  340   b  may run at least one CGI (Common Gateway Interface) script that allows entry and processing of input search strings provided by clients. 
     Contributor  340  communicates with document repository  319  via T 1  line  330   a , Internet  340 , T 1  line  330   b  and contributor gateway server  340   b . Documents generated at contributor site  340  may be transmitted to document repository  319  via T 1  line  330   b , Internet  340  and contributor gateway server  340   a . Contributor gateway server  340   a  runs a number of processes (described in detail below) related to receiving documents and input symbols from contributors, normalizing received input symbols, searching master symbol database  420  and/or categorical symbol database  425 , and archiving documents submitted by various contributors. Contributor  340  may submit documents to document repository  319  electronically over Internet  340  in any number of formats including text files, PDF (Portable Document Files), Microsoft Word files, etc. The remaining components contained within document repository  319  are discussed below with reference to FIG.  4 . 
     FIG. 4 is a block diagram depicting the architecture of a portion of a document repository system for archiving and retrieving symbolically linked documents according to one embodiment of the present invention. Document repository  319  contains contributor gateway server  340   a , client gateway server  340   b , symbol server  410 , master symbol database  420 , categorical symbol database  425 , relational database  430 , contributor historical pattern database  440 , document file database  450 , full text database  460 , client database  470 , normalization table database  417  and object database  415 . Although only one contributor  340  and one client  305  are depicted in FIG. 4, the system is designed to function with multiple contributors and clients. 
     Symbol server  410  receives and processes requests from contributor gateway server  340   a  and client gateway server  340   b  to search the master symbol database  420  and/or the categorical symbol database  425 . In particular, as described in more detail below, symbol server  410  runs a process to receive at least one normalized input symbol from either contributor gateway server  340   a  or client gateway server  340   b  and return a corresponding parent identifier  110  retrieved from symbol database  420  if a master symbol matching the normalized input symbol is found in master symbol database  420 . The symbol server  410  may also return a corresponding categorical symbol retrieved from the categorical symbol database  425  if the request includes a search of the categorical symbol database  425  for a categorical symbol that is included within the normalized input symbol. 
     Master symbol database  420  stores a list of all master symbols (e.g.,  115   a - 115   c ) and their associated parent identifiers  110 . For example, according to one embodiment, master symbol database  420  stores a set of master symbols pertaining to securities issued by companies throughout the world. According to one embodiment, master symbol database  420  is generated on a periodic basis from a set of source tables that reference all known securities of companies traded throughout the world. The creation of master symbol database  420  is described in more detail below. The categorical symbol database  425  stores a list of all categorical symbols used to categorized the symbolically linked information. According to one embodiment, categorical symbols may be assigned to a plurality of: report emphasis areas, i.e., commodity research, company reports, convertible research, credit research; research methodologies, i.e., fundamental, technical, quantitative or strategic; report objectives, i.e., commentary, forecast news, market data; and primary subject matters. 
     FIG. 5 a  depicts a data structure for storage of master symbol data in a master symbol database according to one embodiment of the present invention. In particular, FIG. 5 a  is a data structure for storing and linking a parent identifier  110  with a master symbol (e.g.,  115   a - 115   c ) structured according to an arbitrary number (N) of symbol segments (e.g.,  120   a   1 - 120   c   3 ). Master symbol database  420  stores one record  505  for each master symbol in the database  420 . Each record  505  consists of parent identifier field  510  and symbol segment fields  520 ( 1 )- 520 (N). The number of symbol segment fields will vary depending upon the symbol template  145  defining the structure of master symbols stored in master symbol database  420  (i.e., the number of symbol segments will correspond precisely to the number of symbol fields comprising each symbol). Parent identifier field  510  and symbol segment fields  520 ( 1 )- 520 (N) are comprised of one or more memory locations for storing information on a storage device such as hard disk drive. For example, according to one embodiment, parent identifier field  510  stores a 32-bit integer value occupying 4 bytes of information. Symbol segment fields  520 ( 1 )- 520 (N) store ASCII text strings of a predetermined length. 
     For example, FIG. 5 b  depicts a particular example of the data structure shown in FIG. 5 a  applied in the context of storage of company security symbols traded throughout the world according to one embodiment of the present invention. According to this embodiment, a record  505  containing three fields  510 ,  520   a  and  520   b  is generated for each security symbol. Fields  520   a  and  520   b  store a root symbol segment corresponding to the name of a company security and a source symbol segment corresponding to a country where that security is traded, respectively. Field  510  stores a parent identifier associated with the master security symbol, i.e., the parent identifier assigned to the company issuing the security. The creation of master symbol database  420  is described in detail below. 
     FIG. 6 depicts a data structure for the storage of documents in a document file database according to one embodiment of the present invention. Document file database  450  stores one record  610  for each document stored in the database. Each record  610  is comprised of document file field  630  and document identifier field  620 . Document file field  630  stores the actual formatted document data of a document. Alternatively document file field  630  may store a pointer that points to a memory location where document data is stored. Document identifier field  620  stores a unique identification code that is assigned to each document stored in document file database  450 . As described below, upon receipt of a document at document repository  319 , a unique document identifier is generated for the received document and stored with the document in document identifier field  620 . Documents may be stored in any number of file formats. For example, documents may be stored as PDF files, Microsoft Word Files, text files, etc. 
     Full text database  460  stores document data in a text format that allows searching document data for particular keywords. According to one embodiment, contributor gateway server  340   a  runs a process to perform conversion of received documents from contributors (e.g.,  140 ) to a text format for storage in full text database  460 . Full text database  460  allows searching and retrieval of documents according to particular search terms contained within the documents themselves. 
     FIG. 7 depicts a data structure used in a relational database for storing information relating to documents stored at a document repository according to one embodiment of the present invention. Relational database  430  serves as a bridge between document file database  450  and master symbol database  420 . In particular, for each document stored in document database, relational database  430  cross-references the document ID  730  of the document to the parent ID  720  corresponding to an object or sub-object referenced in the document. Also, the relational database  430  serves as a bridge between the document file database  450  and the categorical symbol database  425 . Similar to the master symbol data, for each document stored in the document database the relational database  430  cross references the document ID  730  of the document to the categorical symbol corresponding to the categorical symbol referenced in the input symbol of the document. Relational database  430  also stores additional data regarding particular attributes of documents received from contributors. 
     A record  705  is generated in relational database  430  for each document stored at document repository  319 . According to one embodiment of the present invention, each record contains document identifier field  710  parent identifier field  720  contributor ID field  730  master symbol pointer field  740 , categorical symbol field pointer  745 , contributor input symbol field  750  and a predetermined number of contributor element fields (not shown). 
     Document identifier field  710  stores a unique document identifier assigned to the document. The unique document identifier is generated upon receipt of a document at document repository  319 . Parent identifier field  720  stores a parent identifier that relates to an object that is associated with the document. Typically, parent identifier field  720  stores the parent identifier linked to an input symbol submitted by the contributor of the document. As described below in detail below, as part of the archival of new documents submitted by contributors, a contributor input symbol is normalized and a parent identifier linked to a matching master symbol in the master symbol database is retrieved from master symbol database. This parent identifier is stored in parent identifier field  720 . For example, according to one embodiment, in the context of archiving financial documents, parent identifier field  720  stores an identifier of a company that is associated with a document having the document identifier stored in document identifier field  710 . 
     Contributor ID field  730  stores a unique contributor identifier corresponding to the contributor of the document. Master symbol pointer field  740  stores a pointer to a master symbol in master symbol database  420  that is associated with the object of a document. In particular, this pointer points to the matching master symbol found by searching master symbol database  420  using the normalized input symbol provided by the contributor. Categorical symbol pointer field  745  stores a pointer to a categorical symbol in the categorical symbol database  425  that is associated with the categorical symbol within the normalized input symbol submitted by the contributor. Contributor input symbol field  750  stores the input symbol provided by the contributor (prior to normalization) when submitting the document. 
     FIG. 8 depicts a data structure used in contributor historical pattern database for storing information relating to historical symbol use trends of particular contributors according to one embodiment of the present invention. The purpose of contributor historical pattern database  440  is to assist in the normalization of input symbols provided by contributors and allow resolution of ambiguous symbols provided by contributors when submitting documents to document repository  319 . For example, contributors may submit an input symbol with a document that is missing one or more symbol segments. Or, a contributor may submit an input symbol containing one or more symbol segments that cannot be resolved after normalization and searching master symbol database  420 . 
     Contributor historical pattern database  440  stores a record for each contributor providing documents to document repository  319 . Each record consists of a contributor ID field  810 , and a predetermined number of predominant use segment fields  820 ( 1 )- 820 (N). In the example embodiment of the present invention, the number of predominant use segment fields stored in each record  805  will correspond precisely to the number of symbol fields defined by the symbol template  145  for storing master symbols in master symbol database  420 . 
     Contributor ID field  810  stores a unique contributor identifier for each contributor submitting documents to document repository  319 . Predominant use segments  820 ( 1 )- 820 (N) correspond respectively to symbol fields  150 ( 1 )- 150 (N) and each store the most frequently submitted symbol segment corresponding to the respective symbol field for a contributor. 
     For example, in the context of a financial document repository, in which a master symbol database stores company security symbols utilizing the structure ROOT.SOURCE, contributor historical pattern database might store the following records: 
     Record  1   
     Field  810 : Contributor  1  ID 
     Field  820 ( 1 ): &lt;BLANK&gt; 
     Field  820 ( 2 ): GB 
     Record  2   
     Field  810 : Contributor  2  ID 
     Field  820 ( 1 ): &lt;BLANK&gt; 
     Field  820 ( 2 ): US 
     Record  3   
     Field  810 : Contributor  3  ID 
     Field  820 ( 1 ): &lt;BLANK&gt; 
     Field  820 ( 2 ): FR 
     Records  1 - 3  each store predominant use segments for contributors  1 - 3 . The first predominant symbol segment field  820 ( 1 ) is blank for all contributors indicating that no predominant use segment exists for the root field of symbol template  145  shown in FIG. 1 c . The second predominant symbol segment field  820 ( 2 ) contains entries for contributors  1 - 3 . In particular, record  1  shows that GB is the most predominant symbol segment submitted by contributor  1 , US is the most predominant symbol segment submitted by contributor  2  and FR is the most predominant symbol segment submitted by contributor  3 . 
     Thus, according to one embodiment, if contributor  2  were to submit an input symbol that were missing a symbol segment corresponding to source field  150   b , contributor historical pattern database would be searched to determine that ‘US’ is the most predominantly used segment for the source field submitted by contributor  2 . Thus, the symbol segment ‘US’ would be assigned as the source segment for the input symbol provided by the contributor. 
     Below shows another exemplary embodiment in the context of the financial document repository, in which a master symbol database stores company security symbols utilizing the structure of ROOT.CATEGORY, contributor historical pattern database might store the following records: 
     Record  4   
     Field  810 : Contributor  1  ID 
     Field  820 ( 1 ): &lt;BLANK&gt; 
     Field  820 ( 2 ): Commodity Research 
     Record  5   
     Field  810 : Contributor  2  ID 
     Field  820 ( 1 ): &lt;BLANK&gt; 
     Field  820 ( 2 ): Industry Reports 
     Record  6   
     Field  810 : Contributor  3  ID 
     Field  820 ( 1 ): &lt;BLANK&gt; 
     Field  820 ( 2 ): Company Reports 
     Records  4 - 6  each store predominant use segments for contributors  1 - 3 . The first predominant symbol segment field is again left blank indicating that no predominant use segment exists for the root field of symbol template  145  shown in FIG. 1 c . The second predominant symbol segment field  820 ( 2 ) shows respectively the most predominant symbol segments submitted by the contributors: Commodity Research for contributor  1 ; Industry Reports for contributor  2 ; and Company Reports for contributor  3 . The generation of historical pattern database  440  is described in more detail below. 
     FIG. 9 depicts a data structure used in a client database for storing information relating to client preferences according to one embodiment of the present invention. Client preferences database  470  stores client preference data regarding default symbol segments in order to assist in the normalization of input symbols provided by clients. Similar to contributor historical pattern database, the purpose of client database  440  is to allow resolution of ambiguous symbols provided by clients when submitting documents to document repository  319 . However, according to one embodiment, client database is not created by analyzing historical trends of clients, but rather by allowing clients to choose default symbol segment preferences in advance. For example, clients may submit an input symbol for searching document repository  319  that is missing one or more symbol segments. Or, a client may submit an input symbol containing one or more symbol segments that cannot be resolved after normalization and searching master symbol database  420 . 
     Client historical pattern database  440  stores a record for each client using document repository  319 . Each record consists of a client ID field  910 , and a predetermined number of client preference segment fields  920 ( 1 )- 920 (N). The number of client preference segment fields stored in each record  905  will correspond precisely to the number of symbol fields defined by symbol template  145  for storing master symbols in master symbol database  420 . 
     Client ID field  910  stores a unique client identifier for each client using document repository  319 . Client preference segments  920 ( 1 )- 920 (N) correspond respectively to symbol fields  150 ( 1 )- 150 (N) in symbol template  145  and each respectively stores a client defined default preference segment corresponding to the respective symbol field for a client. 
     For example, in the context of a financial document repository, in which a master symbol database stores company security symbols utilizing the structure ROOT.SOURCE, client database might store the following records: 
     Record  1   
     Field  910 : Client  1  ID 
     Field  920 ( 1 ): &lt;BLANK&gt; 
     Field  920 ( 2 ): GB 
     Record  2   
     Field  910 : Client  2  ID 
     Field  920 ( 1 ): &lt;BLANK&gt; 
     Field  920 ( 2 ): US 
     Record  3   
     Field 910: Client 3 ID 
     Field  920 ( 1 ): &lt;BLANK&gt; 
     Field  920 ( 2 ): FR 
     Records  1 - 3  each store client preference segments for clients  1 - 3 . The first client preference segment field  920 ( 1 ) is blank for all clients indicating that no client preference segment has been established for the root field of symbol template  145  shown in FIG. 1 c . The second client preference segment field  920 ( 2 ) contains entries for contributors  1 - 3 . In particular, record  1  shows that client  1 - 3  have selected ‘US’, ‘GB’ and ‘FR’ for the source field  150   b  respectively. 
     Thus, according to one embodiment, if client  2  were to submit an input symbol that were missing a symbol segment corresponding to the source field  150   b , client historical pattern database would be searched to determined that ‘US’ is the default symbol segment selected by client  2  for the source field. Thus, the symbol segment ‘US’ would be assigned as the source segment for the input symbol provided by the client. 
     Below shows another exemplary embodiment in the context of the financial document repository, in which a master symbol database stores company security symbols utilizing the structure of ROOT.CATEGORY, contributor historical pattern database might store the following records: 
     Record  4   
     Field  910 : Client  1  ID 
     Field  920 ( 1 ): &lt;BLANK&gt; 
     Field  920 ( 2 ): Commodity Research 
     Record  5   
     Field  910 : Client  2  ID 
     Field  920 ( 1 ): &lt;BLANK&gt; 
     Field  920 ( 2 ): Industry Reports 
     Record  6   
     Field  910 : Client  3  ID 
     Field  920 ( 1 ): &lt;BLANK&gt; 
     Field  920 ( 2 ): Company Reports 
     Records  4 - 6  each store client preference segments for clients  1 - 3 . The first client preference symbol segment field is again left blank indicating that no client preference use segment exists for the root field of symbol template  145  shown in FIG. 1 c . The second client preference symbol segment field  920 ( 2 ) shows respectively the most client preference symbol segments submitted by clients  1 - 3 : Commodity Research for client  1 ; Industry Reports for client  2 ; and Company Reports for client  3 . Therefore according to this embodiment, if client  3  were to submit an input symbol that is missing a symbol segment corresponding to the categorical field  150  ( 2 ), the client historical pattern database would be searched to determine that “Company Reports” is the default symbol segment selected by client  3  for the categorical field. Accordingly, the symbol segment “Company Reports” would be assigned as the categorical segment for the input symbol. 
     FIG. 10 depicts a data structure used in a normalization table database relating to various symbol sets according to one embodiment of the present invention. The function of normalization table database  417  is to assist in the normalization of input symbols provided by contributors or clients. Because clients and contributors may provide input symbols using any number of symbol sets in existence, a mechanism is used to negotiate between the various symbol sets in circulation and the set of master symbols stored in master symbol database  420 . For example, with respect to financial symbols, contributors and clients may submit input strings using any number of vendor symbols or exchange symbols. Normalization table database  417  allows conversion and negotiation between different symbol sets that may be in circulation. 
     For example, according to one embodiment, normalization table database  417  stores information relating symbol sets of various financial information vendors and exchanges to the master symbols stored in master symbol database  420 . In particular, one contributor might use the symbol segment ‘GB’ to refer to Great Britain while another contributor might use the symbol segment ‘EN’. However, master symbols stored in master symbol database  420  might use the symbol segment ‘UK’ to refer to Great Britain. Thus, if a client submits a symbol containing the symbol segment ‘GB’ it must be normalized to ‘UK’ so it can be searched against the master symbols stored in master symbol database  420 . 
     According to one embodiment, normalization table database stores a record  1005  for each symbol in circulation that might be used by a contributor or client. Record  1005  includes symbol owner field  1010 , owner symbol segment field  1020  and master symbol segment field  1030 . Symbol owner field  1010  stores a unique identifier of an entity or organization to which a particular symbol segment in circulation belongs (e.g., an exchange or a vendor). Owner symbol segment field  1020  stores an ASCII string of the symbol segment employed by a particular symbol owner (e.g., a vendor or exchange). Master symbol segment  1030  field stores the corresponding symbol segment that would be stored in master symbol database  420 . Thus, master symbol segment field  1030  stores a symbol segment corresponding to the normalization of the owner symbol segment stored in field  1020 . 
     For example, normalization table database might contain two records as follows. 
     Record  1   
     Field  1 : GB 
     Field  2 : Symbol Owner  1  ID 
     Field  3 : EN 
     Record  2   
     Field  1 : GB 
     Field  2 : Symbol Owner  2  ID 
     Field  3 : UK 
     In this case, record  1  indicates that symbol owner  1  uses the symbol segment ‘EN’ to refer to Great Britain, while symbols stored master symbol database  420  use the symbol segment ‘GB’ to refer to Great Britain. Record  2  indicates that symbol owner  2  uses the symbol segment ‘UK’ to refer to Great Britain, while symbols stored in master symbol database use the symbol segment ‘GB’ to refer to Great Britain. Thus, if a client or contributor provided an input symbol in a symbol format corresponding to symbol owner  2  and the input symbol contained the symbol segment ‘UK’, the symbol segment ‘UK’ would be normalized to ‘GB’ because this is the corresponding symbol segment used to represent Great Britain for all master symbols stored in master symbol database  420 . 
     FIG. 11 depicts a data structure used in an object database for storing information relating an object to a parent identifier according to one embodiment of the present invention. A record  1105  is generated for every object in object space  105 . Each record  1105  includes two fields, object name field  1110  and parent ID field  1120 . Object name field  1110  stores the name of an object and parent ID field  1120  stores a unique parent identifier associated with that object. For example, according to one embodiment of the present invention, object database  415  stores information regarding companies traded throughout the world. In this case, a record  1105  is generated for each company. Object name field  1110  stores a name of a company and parent ID field  1120  stores a unique parent identifier associated with the company named in field  1110 . 
     FIG. 12 is a flowchart of steps for the creation of a master symbol database according to one embodiment of the present invention. According to one embodiment, one or more symbol source files and object database  415  are utilized in the creation of master symbol database  420 . For example, in the context of building a master symbol database of company securities, a number of weekly files of exchange codes and vendor codes for securities of companies around the world are processed to build master symbol database  420 . The frequency of re-building master symbol database  420  will vary depending upon how quickly symbol information changes. 
     In step  1210 , the procedure is initiated. In step  1220 , the next symbol from the source file is retrieved. In step  1230 , the retrieved symbol is normalized according to a set of character rules. For example, according to one embodiment in which the master symbols refer to securities of companies traded throughout the world, the following character rules are applied to each symbol from available symbol source files: 
     1. All special characters such as ‘@’ and ‘=’ are changed to ‘/’; 
     2. All alphabetic characters are converted to uppercase; 
     3. All leading zeros from numeric symbols are removed. 
     In step  1240 , process rules are applied. According to one embodiment of the present invention in which master symbol database  420  stores master symbols referencing securities of companies traded throughout the world, the following process rules are applied: 
     1. Duplicate symbols referring to the same security of the same company traded in the same country are removed; 
     2. Specific country rules are applied. 
     In step  1250 , the normalized symbol is assigned a parent identifier  110 . This is accomplished by determining the object corresponding to the symbol in object database  415 . In step  1260 , the normalized symbol  115  is stored in master symbol database  420 . In step  1270 , the parent identifier  110  is stored in master database  420  so that it is linked to the master symbol. In step  1280 , it is determined whether all symbols in the source file have been processed. If not (‘no’ branch of step  880 ), the next symbol is examined. If so (‘yes’ branch of step  1280 ), the procedure ends. 
     Contributor gateway server  340   a  runs a number of processes to manage the receipt and archival of documents received from contributors (e.g.,  340 ). In order to provide this functionality, contributor gateway server  340   a  interacts with a number of databases including contributor historical pattern database  440 , normalization table database  417 , document file database  450 , fill text database  460  and relational database  430  as well as symbol server  410 . 
     FIG. 13 is a block diagram depicting information flow between various servers and databases at document repository  319  relating to the automatic archival of documents received from a contributor according to one embodiment of the present invention. In particular, contributor gateway server  340   a  runs a process to receive a document file  1310  and input symbol from a contributor. According to one embodiment of the present invention, in order to submit a document, contributor  340  may transmit a header file  1320  in a structured data format containing information about the document  1310 . Header file  1320  (not shown) is composed of a number of fields including, for example, an input symbol field as well as contributor information such as the contributor&#39;s name and date of the document. Thus, contributor gateway server  340   a  may run an additional process to parse header file  1320  to extract information regarding particular documents submitted. 
     Upon extracting an input symbol from a received header file  1320 , contributor gateway server  340   a  runs a process to normalize the input symbol according to a set of character and process rules. In conducting this process, contributor gateway server  340   a  may search normalization table database  417  using one or more input symbol segments  1325  to obtain normalized symbol segments  1327  from normalization table database  417  in order to resolve certain symbol segments. If symbol segments remain unresolved, contributor gateway server  340   a  may retrieve statistical data regarding the contributor&#39;s historical patterns  1360  from contributor historical pattern database  440  to attempt to resolve the symbol segments. 
     After normalization, contributor gateway server  340   a  transmits the normalized input symbol to symbol server  410  ( 1340 ). Symbol server  410  searches master symbol database  420  using the normalized symbol in order to retrieve a parent identifier  1340  linked to a matching master symbol in master symbol database. If symbol server  410  finds a matching master symbol in master symbol database  420 , it returns the corresponding parent identifier  110 . Otherwise symbol server  410  transmits a message indicating the non-verified symbol  1340 . Also, the symbol server  410  searches the categorical symbol database  450  using the normalized input symbol in order to determine whether the input symbol includes a categorical symbol residing in the categorical symbol database  450 . If a matching categorical symbol is found, then the contributor gateway server  340   a  links categorical identifying data to a unique document identifier. This categorical identifying data is used for archival and retrieval of documents based upon the categorical symbol. If the categorical symbol is not included in the input symbol, then contributor gateway server  340   a  may retrieve statistical data regarding the contributor&#39;s historical patterns  1360  from the contributor historical pattern database  440  in order to assign categorical identifying data to the document. 
     Contributor gateway server  340   a  then generates the unique document identifier, and stores the document identifier, parent identifier  110  and contributor data ( 1350 ) in relational database  430 . If the normalized input symbol cannot be verified, contributor gateway server  340   a  may search relational database  430  using the contributor input symbol ( 1365 ) to determine whether the input symbol was previously linked to a parent identifier  110 . Contributor gateway server  340   a  then stores the document so that it is linked to the document identifier ( 1370 ) in document file database  450 . 
     Contributor gateway server  340   a  may also execute additional processes to negotiate between different document file formats. Thus, for example, contributor gateway server  340   a  may execute routines to convert a document received in a particular file format to a text format ( 1380 ) for storage in full text database  460 . 
     FIG. 14 is a flowchart of steps for the automatic archival of a document at a document repository according to one embodiment of the present invention. In step  1410 , a document file and header file are received at document repository  319 . In step  1415 , an input symbol is extracted from header file  1415 . In step  1420 , the input symbol is normalized according to a set of character and process rules. In step  1425 , it is determined whether the input symbol contains all symbol segments. If not (‘no’ branch of step  1425 ), predominant symbol segments used by the contributor are retrieved from historical pattern database  440  (step  1440 ). In step  1430 , normalization table database  417  is consulted to resolve certain symbol segments. In step  1445 , the master symbol database  420  and categorical symbol database  425  are searched using the normalized symbol. If a matching master symbol and categorical symbol are found (‘yes’ branch of step  1450 ), a document identifier is generated (step  1455 ). The document identifier, parent identifier  110  and structured data from header file  1420  is then stored in relational database  430  (step  1460 ). In step  1465 , the document and document identifier are stored in document database  450  so that the document identifier is linked to the document. In step  1470 , the text of the document is stored in full text database  460 . The procedure ends in step  1480 . 
     If a matching master symbol and categorical symbol are not respectively found in the master symbol database  420  and the categorical symbol database  425 , then relational database  430  is searched using the contributor submitted symbol (step  1452 ). If the contributor submitted symbol was previously used and linked to a parent identifier  110  (‘yes’ branch of step  1454 ), then the corresponding parent identifier  110  is used. If the contributor submitted symbol has been previously used and linked to a predominant categorical symbol segment, then the predominant categorical symbol segment is also assigned to the document. Otherwise, the procedure fails (‘no’ branch of step  1454 ). This may occur because a contributor may have submitted a document in the past using a symbol that could not be resolved. The symbol might however be resolved manually using human input. In this case, relational database  430  would store a record  705  for the document in which contributor input symbol field  750  stores the input symbol provided by the contributor that was manually resolved. 
     Client gateway server  340   b  runs a number of processes to manage the processing of search strings and retrieval of documents requested by clients (e.g.,  305 ). In order to provide this functionality, client gateway server  340   b  interacts with a number of databases including client database  470 , document file database  450 , full text database  460 , normalization table database  417 , relational database  430  as well as symbol server  410 . FIG. 15 is a block diagram depicting information flow between various servers and databases at document repository  319  relating to the automatic retrieval of documents based upon an input symbol provided by a client  305  according to one embodiment of the present invention. 
     In particular, client gateway server  340   b  runs a process to provide a GUI that allows input of search requests by clients. According to one embodiment client gateway server  340   b  runs a CGI script that allows the input and processing of input symbols  1510  provided by clients  305  relating to particular document requests. 
     Client gateway server  340   b  runs a process to normalize input symbols  1510  provided by clients. Upon receipt of an input symbol, client gateway server  340   b  may retrieve information  1560  from client database  470  regarding default symbol segments if a client  305  submits an input symbol missing a particular segment. Client gateway server  340   b  may also submit one or more input symbol segments  1525  to search normalization table database  417  to return corresponding master symbol segments  1527 . 
     The normalized input symbol  1520  is transmitted to symbol server  410 . Symbol server  410  then uses the normalized input symbol to search master symbol database  420  to find a parent identifier linked to a matching master symbol in master symbol database  420 . Using the parent identifier  110  returned from symbol server  410 , client gateway server  340   b  searches relational database  430  to obtain a list of document identifiers and document headlines  1540  corresponding to the submitted parent identifier  110 . The document headlines are processed by client gateway server  340   b  for display to client  305 . Upon receiving selections from the clients, client gateway server  340   b  retrieves selected documents  1550  from document file database  450 . If a client seeks documents within a particular category or associated with a categorical symbol then the symbol server  410  uses normalized input symbol  1520 , which includes a categorical symbol, to search the categorical symbol database in order to find a matching categorical symbol. Symbol server  410  returns the matching categorical symbol which the client gateway server  340   b  receives in order to search the relational database  430  to obtain a list of document identifiers and document headlines  1540  corresponding to the submitted categorical symbol. 
     FIG. 16 is a flowchart of steps for the automatic retrieval of documents at a document repository based upon a client submitted input symbol according to one embodiment of the present invention. In step  1610 , an input symbol  1510  is received from client  305 . In step  1620 , normalization rules such as character and process rules are applied to the received input symbol  1510 . In step  1625 , it is determined whether the normalized symbol contains all symbol segments. If not (‘no’ branch of step  1625 ) client preference segments retrieved from client database  470  are used for the missing segments (step  1630 ). In step  1645 , master symbol database  420  and categorical symbol database  425  are searched using the normalized symbol  115 . If a matching master symbol is found in master symbol database  420  (‘yes’ branch of step  1650 ), relational database  430  is searched using the parent identifier  110  linked to the master symbol in order to generate a list of document identifiers and document headlines. If the symbol is not found (‘no’ branch of step  1650 ), the procedure fails. Alternatively, in the case of a categorical search, if a matching categorical symbol is found then the relational database  430  is searched using the categorical symbol in order to generate a list of document identifiers which are linked to the categorical symbol. In step  1665 , document headlines pertaining to each found document are displayed for selection. In step  1670 , client gateway server  340   b  accepts selection of document headlines by client  305 . Based upon the selected document identifiers, the corresponding documents are retrieved from document file database  450 . The procedure ends in step  1680 . 
     FIG. 17 is a flowchart depicting a set of steps for generating a contributor historical database according to one embodiment of the present invention. In step  1702 , the procedure is initiated. In step  1710 , the next record in relational database  430  is retrieved. In step  1720 , the record from relational database  430  is analyzed. In particular, master symbol pointer field  740  is used to determine a master symbol referenced in the record. The master symbol is analyzed to update a table, which tallies statistical information regarding predominantly submitted symbol segments submitted by various contributors. This table (not shown) may be implemented, for example, using a data structure such as an array. In regard to developing statistical data for categorical purposes, step  1725 , the categorical symbol field  745  is used to determine a categorical symbol referenced in the record. The categorical symbol analysis updates a table and tallies statistical information regarding predominantly submitted categorical symbol segments. In step  1730 , it is determined whether all records in relational database  430  have been analyzed. If not (‘no’ branch of step  1730 ), the next record in relational database  430  is analyzed. If so (‘yes’ branch of step  1730 ), the information generated in the statistical table is stored in historical pattern database  440  (step  1740 ). The procedure ends in step  1750 . 
     For example, the following table might be generated after an analysis of relational database  430 : 
     
       
         
           
               
               
               
               
             
               
                   
               
               
                 Contributor 
                 Symbol Field #1 
                 Symbol Field #2 
                 Symbol Field #3 
               
               
                   
               
             
            
               
                 1 
                 IBM 40 
                 GB 30 
                 CRes 35 
               
               
                   
                 T 55 
                 US 50 
                 DerRep 10 
               
               
                   
                   
                 FR 15 
                 IdRep 50 
               
               
                 2 
                 IBM 5 
                 GB 4 
                 EconRep 5 
               
               
                   
                 T 2 
                 US 1 
                 CredRes 2 
               
               
                   
                   
                 FR 1 
               
               
                 3 
                 IBM 450 
                 DE 550 
                 ConvRes 395 
               
               
                   
                 T 275 
                 US 450 
                 CredRes 550 
               
               
                   
                 QW 525 
               
               
                   
               
            
           
         
       
     
     Thus, according to the analysis the most frequently submitted symbol segments for symbol field  1  were ‘T’, ‘IBM’ and ‘QW’ for contributors  1 ,  2  and  3  respectively. In addition, the most frequently submitted symbol segments for symbol field  2  were ‘US’, ‘GB’ and ‘DE’ for contributors  1 ,  2  and  3  respectively. Finally, the most frequently submitted symbol segments for symbol field  3  were IdRep, EconRep and ConvRes for contributors  1 ,  2  and  3  respectively. Thus, based upon this information, for contributor  1 , contributor historical pattern database  440  would store a separate record  805  for each contributor. In particular, based upon this analysis the records would store: ‘T’, ‘US’ and ‘IdRep’; ‘IBM’, ‘GB’ and EconRep; and ‘QW’, ‘DE’ and ConvRes, in predominant use segment fields  820 ( 1 ),  820 ( 2 ) and  820 ( 3 ) for contributors  1 ,  2 , and  3  respectively.