JP2000172698A - System and method for retrieving document and computer-readable recording medium with program for executing the method recorded therein - Google Patents

Abstract

PROBLEM TO BE SOLVED: To constitute an information retrieval system with minimum labor by easily selecting a document intended by a user from the retrieved result and utilizing the document for data base retrieval, when a document data base is retrieved by a keyword retrieval conditional expression. SOLUTION: Retrieval conditions are inputted (10), and a document data base (20) storing plural documents is retrieved (30) by the retrieval conditions. The degree of collation is found (40) for each retrieval key to each retrieved document, and based on this collation degree, the list of an expression (52) enabling comprehension of the condition of collation with the retrieval key and the retrieved document is displayed (50) while relating them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to displaying a list of document search results in a document search system.

[0002]

2. Description of the Related Art With the digitization of documents and the spread of the Internet, the need for document retrieval systems has increased.
In a document search system, usually, a user specifies search terms or search character strings (hereinafter referred to as "search keys") or specifies search conditions combined by an AND / OR logical operator and matches the search conditions. It is possible to search for a document, present the searched document as a search result in a list display, and, if necessary, display and display the document specified by the user. There is also a document search system that can specify a natural language sentence or part or all of a document as a search condition. The list of documents is
Usually, the part corresponding to the title of the document is displayed as name information. In recent years, however, by displaying effective contraction information such as the beginning of the document, important keywords, and a summary sentence, the Before they directly reference the document,
A function has been provided to help determine whether the document is the one the user wants.

[0003]

However, the above-mentioned conventional method has the following problems. Suggested titles, beginnings, key keywords, and summaries
It is not oriented to user search criteria. Therefore,
As information reflecting the user's search conditions, a score (score) is attached to the degree of matching with the user's search conditions, and a list of documents is arranged in that order, and the score is added, and the user's search conditions are added. In addition, information corresponding to the information is added.

However, if there is only one search key,
A score is sufficient, but in reality, when there are multiple search keys, the score does not reflect how the search keys are weighted by the user that cannot be expressed in the search conditions. There was a face that was not helpful. or,
Because it is not clear how important the search key in the search expression is for each document,
Documents could not be selected visually.

In order to solve this problem, Japanese Patent Application Laid-Open No. 10-49 discloses
According to the technique disclosed in Japanese Patent No. 543, a linguistic feature indicating a user's search intention is classified, and a keyword (input feature) indicating a characteristic of the classification is selected, and then the document group is classified. After classifying, the score is calculated for each class, and the documents and the score for each class are displayed in descending order of the score,
By confirming the classification and evaluation points, it helps to efficiently narrow down documents that are close to the intended search. However, a new and difficult task of classifying such linguistic features must be performed in order to search for documents, and the system requires a thesaurus, a concept dictionary, and a co-occurrence dictionary. The problem that comes out.

In order to solve such a problem, according to the present invention, in a document search system for searching for a document intended by a user according to a generally used keyword search condition expression, “the searched document is selected. Therefore, it is possible to confirm for yourself how much a document reflects the user's search intention by presenting which search key in the search condition specified by the user and how much contributed to it by matching degree " It is an object of the present invention to enable such a document search system to be configured with minimum effort.

[0007]

According to a first aspect of the present invention, there is provided a document search system for searching a document database by inputting search conditions and displaying a list of search results. A document database in which a plurality of documents are stored, a search unit for searching the document database with the search condition input in the search condition input unit, and a search condition for each document searched by the search unit. A collation degree evaluator for obtaining a collation degree for each search word or search character string (hereinafter referred to as a “search key”); and a search result display section for displaying a list of documents searched by the search section. A document retrieved by the retrieval unit and a collation status are added to the result display unit by adding a collation status expression unit that expresses the collation status with the search key based on the collation obtained in the collation evaluation unit. It was to display a list in association with the expression obtained in the current part.

According to a second aspect of the present invention, there is provided a document search system for searching a document database by inputting a search condition and displaying a list of search results. A search interface unit that sends a search condition input by the search unit and receives a search result of a document database storing a plurality of documents with the search condition, and a search interface unit that receives the search result received by the search interface unit. And a search result evaluator for obtaining a match degree for each search word or search character string (hereinafter referred to as a “search key”) in the search condition, and a list of documents of the search results received by the search interface unit And a matching status that the search result display unit expresses so that the matching status with the search key can be understood based on the matching score obtained by the matching score evaluation unit. And to display a list in association with expression and obtained written and collating status representation of the search result received in the search interface unit adds the current section.

[0009] The document search system according to claim 3 is based on claim 1.
Alternatively, in the document retrieval system according to claim 2, the collation status expressing section arranges the retrieval keys in the order of the collation degree evaluation value.

[0010] According to a fourth aspect of the present invention, there is provided a document search system.
Alternatively, in the document search system according to claim 2, the collation status expression unit is a figure that allows the configuration of a search condition expression to be understood.

According to a fifth aspect of the present invention, there is provided the document search system according to the first aspect.
Alternatively, in the document search system according to claim 2 or 4, the collation status expressing section is configured to recognize the difference in the collation evaluation value by the decoration of the figure for the collation degree for each search key.

According to a sixth aspect of the present invention, there is provided the document search system according to the first aspect.
Alternatively, in the document retrieval system according to claim 2 or 4, the collation status expressing section is configured to recognize the evaluation value of the collation degree for each search key so that the difference in the evaluation value of the collation degree can be recognized depending on the shape of the graphic.

According to a seventh aspect of the present invention, there is provided a document search method for searching a document database according to a search condition and displaying a list of search results, wherein the search condition is input and the document database storing a plurality of documents is stored in the document database. A search is performed according to the search condition, a matching degree is obtained for each searched key for each of the searched documents, and an expression that allows the user to know the matching state with the search key is associated with the searched document based on the matching degree. To display a list.

The computer-readable recording medium storing the program according to the present invention inputs a search condition, searches a document database storing a plurality of documents according to the search condition, and stores a search result in each of the searched documents. On the other hand, a program for obtaining a degree of collation for each search key and recording a list in which an expression that allows the user to know the state of collation with the search key based on the degree of collation is associated with the retrieved document is displayed.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction and operation principle of the present invention will be described below using three embodiments.

1. Embodiment 1 (Single Type) A first embodiment of the present invention will be described with reference to FIGS. (1) Overall Configuration FIG. 1 shows the overall configuration of a document search system (hereinafter, referred to as the present system) of the present embodiment. 1 is input means, 2 is display means, 3 is CPU, 4 is memory, and 5 is storage means. The input unit 1 includes a keyboard, a mouse, a touch panel, and the like, and is used for inputting information to the present system. The display means 2 displays output information from the present system, information input from the input means 1, and the like. CP
U3 is a part of the system (a search condition input part described later,
A program of a search unit, a collation evaluation unit, a search result display unit, a collation status expression unit, etc.) is operated. The memory 4 holds information temporarily created when each unit of the system is executed by the CPU 3, programs of each unit, and the like. The storage unit 5 holds a document database that holds a group of documents, a program of each unit of the present system, and the like.

FIG. 2 is a diagram showing a functional configuration of the present system. The search condition input unit 10 allows a search condition expression for a search input from the input unit 1 to be input, and inputs the search condition expression to the search unit 20.
Send to The document database 20 is a database for registering and managing a plurality of documents, and is held in the storage unit 5 and managed using an existing database such as a relational database management system. The information managed by this database includes at least information of a title and document contents for one document. The search unit 30 searches the document database 20 using the search condition formula given from the search condition input unit 10 and sends the search result to the matching degree evaluation unit. The matching degree evaluation unit 40 evaluates the matching degree of each document in the search result for each search key in the search condition expression. The search result display unit 50 receives the searched documents and their matching degrees and displays them in a list on the display unit 2. At this time, the matching status expressing unit 52 of the search result display unit 50 converts the matching degree of the search key into a form that can be output according to a user's instruction or an expression method predetermined by the system.

(2) Processing Flow The processing flow of the present system will be described below with reference to the flowchart of FIG.

Step S100: The user inputs from the input means 1 (for example, a keyboard or the like) a search condition expression expressed as a logical expression in units of a search word or the like (search key) for a required document. For example, a search condition formula for searching the document database 20 for a document having the search key "weapon" and having either the search key "export control" or the "export mitigation" has the following format. Weapons & (Export control | Export mitigation) where & is the logical product (AND operator), | is the logical sum (O
(R operator) and () indicate priority ranges. In other cases, the simplest case is just a single search key,
A plurality of search keys can be arranged without using an operator, and can be described in the meaning of “include all” or “include any”. Furthermore, part or all of a natural language sentence or a document can be accepted as a search condition. However, in this case, it is not necessarily based on the understanding of the contents, and the words included in the natural language sentence or the document are regarded as a search key group, and they are treated in a logical OR manner, or are included in the search condition and in the document database. There is a method of regarding a word group in each document as a vector, and the like. In this embodiment, a description will be given of a search condition expression represented by a logical expression.

Step S110: The input search condition expression is interpreted, and a document matching the search condition expression is searched from the document database 20. As a method for realizing this, for example, a search key frequency table 200 for each document (FIG. 4)
Is created, and a document that matches the condition is selected from the appearance frequency of the search key and the search condition expression. For this matched document,
A document list table 300 (FIG. 5) including the following information is created. Document ID (identifier) Title Frequency of occurrence of search keys in this document (for all search keys) Note that search key frequency table 200 is not created, and only those that match at the time of searching each document are listed in document list table 300. It may be directly created as.

Step S120: For each document in the searched document list table 300, the degree of collation of each search key of the search condition formula is calculated (FIG. 7). In the above example, how much each of the three search keys “weapon”, “export control”, and “export mitigation” contribute to each document is evaluated as a matching degree (details will be described later).

Step S130: Document list table 30
Based on the collation degree set to 0, a collation situation expression for each search key is generated for each document. At the time of generating the expression, the user can change the format of the situation to be displayed from the input unit 1 by specifying the user. If not specified, the format is a predetermined format (details will be described later).

Step S140: A list of search documents (for example, a list of document titles) to which the result is added with the collation status for each search key for each document is displayed on the display means 2 such as a display (details will be described later). .

(A) Evaluation of collation degree (step S120) Evaluation of the collation degree of the present system is performed using the importance of each search key (word). There are various calculation methods for the importance of this word as follows.・ The frequency of occurrence (tf: term frequency) in the document ・ The reciprocal value (idf: invert) of the document frequency (the number of documents in which the word appears in the entire document database df: documentfrequency)
ed df) ・ Log value of idf (this may be called idf again) ・ Product of tf and idf

In the present system, the evaluation is made based on the last raised "product of logarithmic value of tf and idf (calculated here as log (1000 / df))". In this case, for the entire document database 20, the number of documents (document frequency: df) appearing for each word is counted in advance, calculated as the importance of the word by the above formula, and the word importance table 400 (FIG. 6) is calculated. create. Word importance table 400
Has the following entry: Word Appearance frequency of this word in the database Importance of this word (calculated by the above formula) Therefore, the matching degree of each search key of each document is determined by the frequency of each search key in the document list table 300 in the document. And the importance of the word (search key) in the word frequency table 400. As a result, a collation degree table 500 having the next entry is created. FIG. 7 shows the calculation result. Document ID Document title Matching degree for each search key

Further, the evaluation value of the degree of collation may be used as the frequency of the retrieval key in the document. At this time, the word importance table 400 is not necessary, and the frequency itself is the evaluation value.

(B) Matching Situation Expression (Step S130) In the present system, a matching situation expression is generated using the matching degree for each search key in the matching degree table 500. There is. Further, expressions can be generated by appropriately combining these.

(I) When the collation state is expressed using the magnitude of the collation degree evaluation value itself (a) A search key that matches the collation state in the document is listed. For example, in the case where the document ID in FIG. 7 is 12, a weapon export control is performed. In the case where the document ID is 1245, an expression such as weapon export control export mitigation is generated. Arranging the search key list in descending order of the matching degree is also effective in knowing the contribution degree of the search key. In the case where the document ID in FIG. 7 is 1245, export mitigation Export control Weapons Alternatively, an expression in a form in which a search key with a matching degree of zero is omitted can be generated using the search condition expression itself. For example, if the document ID in FIG. 7 is 201, weapons & export control If the document ID is 1245, weapons & (export control | export mitigation)

(B) The collation status is listed in a form in which the collation degree is added to the retrieval key that matches the document. In the above example (a), the fact that the collation has been performed and the rank thereof can be known, but the degree of the contribution is not known.
From when the search result list is displayed). For example, when the document ID in FIG. 7 is 201, weapons: 1.34 export control: 2.94, or export controls: 2.94 weapons: 1.34 in order of matching degree. Search keys that are not displayed may not be known to exist or have been omitted.Therefore, when adding a matching degree in this way, even if the matching degree is zero, it may be added to the list. It is valid. Weapons: 2.01 Export restrictions: 0.98 Export mitigation: 0.00 Or, it is also effective to use the search condition expression itself and add a matching degree to the search key in the search condition expression to generate an expression. is there. For example, when the document ID in FIG. 7 is 1245 Weapons: 0.67 & (Export restrictions: 1.96 | Export mitigation: 3.50) Also, for the document ID 999, the place where the matching degree is zero is omitted. Weapons: 2.01 & Export restrictions: 0.98 can be used to create expressions, and zeros may be added without omission. Although the numerical value of the above-mentioned collation degree is directly used as calculated, it may be rounded or multiplied to obtain an integer type. Example: Weapons: 2 & Export restrictions: 1

(Ii) The collation status is represented by the length of the collation degree,
When expressing by area, shape, color difference, shading, decoration difference, etc. (a) List matching conditions in a form in which search keys matching the document are enclosed in figures (circles, rectangles, band graphs, etc.) . Also, arranging these figures in descending order of the matching degree is effective in knowing the contribution degree of the search key. When the matching degree is zero, the corresponding figure may be omitted.

(B) The size is expressed by the length of the dimension line or the length of the bar of the bar graph. (FIG. 8) It may be expressed by adding a collation degree. (C) The size is represented by the area of a figure (circle, rectangle, band graph, etc.) (FIG. 9). (D) Express the size in association with the shape of the figure. Example: Define and use sizes in the order of ◎, ○, □, △, ×, etc. If X is made to correspond to the matching degree of zero, the search key that does not match can be known. (E) The size of a figure (such as ○ or □) is represented by the type of color. Example: Define and use sizes in the order of red, blue, purple, green, yellow, black, white, etc. If a colorless outline-only figure is made to correspond to a matching degree of zero, a search key that does not match can be known.

(F) The size of a figure (○, □, etc.) is represented by the shade of color. Example: Among the above, different shades of color are used, and the darker one is larger in size. In this case, one color or multiple colors as described above may be used. If a colorless outline-only figure is made to correspond to a matching degree of zero, a search key that does not match can be known. (G) When hatching a figure (such as や or □), the size is represented by the difference in the pattern (FIG. 10). If a figure having only a contour without hatching is made to correspond to a matching degree of zero, a search key that does not match can be known. (H) In the search condition formula, the axes of the relationship between the logical form of AND and OR are expressed so as to be orthogonal using a graphic (for example, a band graph). Fig. 11 shows expressions when the search condition formula is weapons & (export control | export mitigation) & Japan, and the matching degrees are weapons: 2, export control: 3, export mitigation: 1, and Japan: 0, respectively. .

(Iii) The collation status is determined by the above (b) and (c).
When expressing using the area of a figure or the length of a line segment as in (h) or (h), the total size is set to the collation degree of the document, and it is calculated as the ratio of the collation degree of each search key. It may be divided and expressed (FIG. 12).

(C) Search Result Display (Step S140) FIG. 13 is an example of a search result list to which the collation status expression of the search condition expression is not added, in which display order numbers and document titles are listed. . When displaying the search result list, the collation degree for each document may be calculated and displayed in the order of the collation degree values. In FIG. 14, not only the title of the document but also a value indicating the degree of collation for each document is shown in [] in the search result list, and the values are sorted and displayed in the order of the magnitude of the value.

Here, the collation degree for each document is obtained as a value obtained by multiplying the sum of the collation degrees of each search key by 10 and rounding it. At this time, the matching degree of the key combination of '&' relation is the sum of the matching degrees of each search key, and the combination of search keys of '|' relation such as “export control” and “export mitigation”
It is calculated as the maximum matching degree of the matching degrees of each search key. The collation degree of the document obtained in this way is created and stored in the collation degree table 500 as an entry called the collation degree of the document. For example, in the document with the document ID of 1245, 0.67 + max (1.96,3.50) = 0.67 + 3.50 = 4.17, and the collation degree of the document is obtained by multiplying the above collation degree by 10 times.
Calculate as a rounded value.

When selecting a document desired by the user from the list display as shown in FIG. 14, the degree of collation for each search key and the contents of the document can be displayed for use as a judgment material.
For example, when the user wants to display the detailed contents, the user double-clicks the target document using the input means 1 such as a mouse, and extracts the contents of the document from the document database 20 by the document ID of the selected document. Can be displayed as a judgment material.

Further, as proposed in the present invention, the degree of collation for each search key can be displayed and used as a judgment material. For this purpose, the user selects from the menu display the user wants to display the collation status in any one of the above-described formats or a combination thereof. Search result display section 50
According to the instruction, the expression generated by the collation status expressing unit 52 of each collation degree of the collation table 500 is displayed on the display unit 2 under the title of each document in a format as shown in FIG. Alternatively, the collation status may be displayed on the display unit 2 between the collation degree of the document and the title in a format as shown in FIG. Alternatively, the collation status may be displayed on the display unit 2 between the collation degree of the document and the title in a format as shown in FIG. Alternatively, the search result list may be displayed in the format shown in FIG. 14, and then the matching status may be displayed individually.

For example, FIG. 15 (b) shows that among the top four documents, the first document describes a lot of “export restrictions” according to the degree of matching given to the search key. Alone can also be said to mention "export mitigation," and could be useful information for users to decide on document selection.

(D) Evaluation Timing In the above-described search unit 30, the document frequency table is calculated for each search key for each document, and the document list table 300 is created. You may. (1) The search unit 30 detects only documents that match the search conditions, and creates only the matched document IDs as the document list table 300. The collation evaluation unit 40 calculates the appearance frequency of each search key in the document for each document registered in the document list table 300. Based on this frequency, the matching degree of the search key is calculated. If necessary, the degree of collation for each document is also calculated. (2) The search unit 30 not only detects a matching document, but also determines the matching degree based on the frequency of occurrence of the matching document for each search key.
Furthermore, if necessary, the degree of collation for each document is calculated.
That is, the search unit 30 and the matching degree evaluation unit 40 are configured to operate integrally.

2. Embodiment 2 (Network Type) The second embodiment of the present invention is an example configured by a client / server type, and FIG. 16 is an overall configuration diagram thereof. The server has the same configuration as that of the first embodiment, and operates as a document database search server. The client is configured by omitting the document database and the search execution part from the configuration of the first embodiment. These one search server and a plurality of clients are connected via a LAN.

FIG. 17 is a functional block diagram of the present embodiment.
The search server and the client work together as follows. When the client 1 uses the present document search system, a search condition is input in the search condition input unit 10 of the client 1, and the search interface unit 60 transmits the search condition to the search unit 30 of the search server, and searches the search server. The unit 30 sends back the document list table 300 of the documents that match the specified search condition to the search interface unit 60 of the client 1. The client 1 calculates the matching degree from the document list table 300 by the matching degree evaluation unit 40, and displays the result on the display unit 2 by the search result display unit 50 based on the matching table 500.

Although the client is provided with the collation evaluation unit 30 on the client side, the search server is provided with the collation evaluation unit 40 to calculate the retrieved document and its collation, and the collation as the result is obtained. The table 500 may be sent back to the search interface unit 60 of the client, and a search result list to which the expression of the matching degree is added from the search interface unit 60 through the search result display unit 50 may be displayed on the display unit 2.

3. Example 3 (Example as a Program) The document search system of the present invention is not limited to the above embodiment. For example, the search condition input unit 10 and the search unit 3 forming the document search system shown in FIG.
0, the respective functions of the matching degree evaluation unit 40 and the search result display unit 50 are programmed, written in advance on a recording medium such as a CD-ROM, and this CD-ROM is mounted on a computer equipped with a CD-ROM drive. By loading the program into a computer, the same function as that of the first embodiment can be realized.

Although the present document search system may be constituted by a client / server system (second embodiment) as shown in FIG. 16, the function of the search unit 30 on the server side is programmed and recorded on a CD-ROM. On the client side, the functions of the search condition input unit 10, the matching degree evaluation unit 40, the search result display unit 50, and the search interface unit 60 may be programmed and recorded on a CD-ROM.

Alternatively, the functions of the search unit 30 and the collation degree evaluation unit 40 on the server side are programmed and recorded on a CD-ROM, and the search condition input unit 10, search result display unit 50 and search interface unit 60 are provided on the client side. May be programmed and recorded on a CD-ROM.

As a recording medium, a semiconductor medium (for example, ROM, IC memory card, etc.), an optical medium (for example, ROM,
Any of DVD-ROM, MO, MD, CD-R, etc.) and magnetic media (for example, magnetic tape, flexible disk, etc.) may be used.

[0047]

As described above, according to the claimed invention, when displaying a list of search results, there are provided various expression means for displaying a matching state with a search key for each document. In addition, by providing simple information according to a user's search condition, a desired document can be efficiently selected from a list of search results.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of a document search system according to the present invention.
FIG.

FIG. 2 is a diagram illustrating a document search system according to a first embodiment of the present invention;
FIG. 2 is a functional configuration diagram.

FIG. 3 is a flowchart illustrating a flow of a process related to the document search system of the present invention.

FIG. 4 is a diagram illustrating a data structure of a search key frequency table.

FIG. 5 is a diagram illustrating a data structure of a document list table.

FIG. 6 is a diagram illustrating a data structure of a word importance table.

FIG. 7 is a diagram illustrating a data structure of a collation degree table.

FIG. 8 is a diagram illustrating an example in which a matching state expression is represented by a length.

FIG. 9 is a diagram illustrating an example in which the size is represented by the area of the figure in the collation situation expression.

FIG. 10 is a diagram illustrating an example in which a matching state expression is represented by a hatched pattern of a figure.

FIG. 11 is a diagram illustrating an example of expressing a structure of a search condition expression in a matching status expression.

FIG. 12 is a diagram showing an example in which the magnitude of the collation degree of a document in the collation state expression is divided and expressed according to the ratio of the collation degree of the search key.

FIG. 13 is an example of a general search result list output screen.

FIG. 14 is an example of a search result list output screen of the present invention.

FIG. 15 is another example of the search result list output screen of the present invention.

FIG. 16 is an overall configuration diagram of Embodiment 2 relating to the information search system of the present invention.

FIG. 17 is a functional configuration diagram of a document search system according to a second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Input means, 2 ... Display means, 3 ... CPU, 4 ... Memory, 5 ... Storage means, 10 ... Search condition input part, 20 ... Document database, 30 ... Search part, 40 ... Matching degree evaluation part, 5
0: search result display section, 52: collation status expression section, 200:
Search key frequency table, 300: Document list table, 4
00: word importance table, 500: collation degree table.

Claims (8)

[Claims] 1. A document search system for inputting search conditions to search a document database and displaying a list of search results, comprising: a search condition input unit for inputting search conditions; a document database storing a plurality of documents; A search unit for searching the document database based on the search condition input by the search condition input unit; and a search word or search character string (hereinafter, “search key”) in the search condition for each document searched by the search unit. A collation degree estimating unit for obtaining a collation degree for each of them, and a search result display unit for displaying a list of documents searched by the search unit, and a collation obtained by the collation degree evaluation unit in the search result display unit. A collation status expression section for generating an expression that allows the user to understand the collation situation with the search key based on the degree is added, and a list obtained by associating the documents retrieved by the retrieval section with the expressions obtained by the collation status expression section Show A document search system characterized in that: 2. A document search system for searching a document database by inputting search conditions and displaying a list of search results, comprising: a search condition input unit for inputting search conditions; and a search condition input by the search condition input unit. A search interface unit for sending and receiving a result of searching a document database in which a plurality of documents are stored under the search condition; and a search term in the search condition for each document of the search result received by the search interface unit Alternatively, the search method further comprises a collation degree evaluation unit for obtaining a collation degree for each search character string (hereinafter, referred to as a “search key”), and a search result display unit for displaying a list of documents of search results received by the search interface unit. The result display unit is provided with a collation status expression unit for expressing the collation status with the search key based on the collation degree obtained by the collation degree evaluation unit, and the search interface is displayed. A document search system wherein a document of a search result received by a face unit and an expression obtained by the matching status expression unit are displayed in a list in association with each other. 3. The document retrieval system according to claim 1, wherein the collation status expression unit arranges retrieval keys in the order of collation degree evaluation values. 4. The document search system according to claim 1, wherein the collation status expression unit is a figure that allows the configuration of a search condition expression to be understood. 5. The document search system according to claim 1, wherein the collation status expression unit comprises:
A document retrieval system characterized in that the evaluation value of the collation degree for each search key is differentiating between the evaluation values of the collation degree by decoration of a figure. 6. The document search system according to claim 1, wherein the collation status expression unit comprises:
A document retrieval system characterized in that the evaluation value of the matching degree for each search key is such that the difference in the evaluation value of the matching degree can be understood depending on the shape of the figure. 7. A document search method for searching a document database according to search conditions and displaying a list of search results,
A search condition is entered, a document database storing a plurality of documents is searched according to the search condition, a matching degree is obtained for each search key for each of the searched documents, and a search is performed based on the matching degree. A document search method characterized by displaying a list in which an expression that indicates a matching state with a key and a searched document are associated with each other. 8. A search condition is input, a document database storing a plurality of documents is searched by the search condition, and a collation degree is determined for each of the retrieved documents for each retrieval key. A computer-readable recording medium which records a program for displaying a list in which an expression such that a matching state with a search key can be recognized based on a search key is associated with a searched document.