KR20120020558A - Folksonomy-based personalized web search method and system for performing the method - Google Patents

Abstract

PURPOSE: A personal web searching method based on folksonomy and system performing the same are provided to recommend a query language by using a folksonomy service for a personal searching service. CONSTITUTION: A server(200) corrects tag data from the Internet and analyzes a folksonomy service for the tag data in order to store clustering information including an URL(Uniform Resource Locator) number and URL. A client(100) transmits the bookmarked URL to the server and stores a user profile and tag information within a cluster based on response data. When a user input the query language, the client transmits the user profile information and the query language to the server in order to provide related key words to the user.

Description

FOXSONOMY-BASED PERSONALIZED WEB SEARCH METHOD AND SYSTEM FOR PERFORMING THE METHOD}

The present invention relates to a method for performing a personalized web search based on folksonomy, and more particularly, to a personalized web search method based on folkson based personal recommendation for a user based on a folkson for personalized search. It is about.

For searching on the Internet, queries are sent to various search engines (e.g., Google, Yahoo, Bing) to search for desired documents among numerous web documents.

Users using these search engines select keywords (or query terms) to get a document containing the desired information. At this time, the keywords selected by the users are mostly short and unclear.

Also, it is difficult for a search system to select and display only documents containing information exactly desired by a user for a query word of unclear meaning. For example, when a user interested in biology sends the keyword Virus as a query to search for documents with the meaning of a biological virus, the search system can only search for short queries that are biological or computer viruses. Difficult to judge with This problem can be solved by additionally selecting a keyword directly related to the user and retransmitting the query including the first selected keyword and automatically displaying a personalized search result based on the information of the user profile in the search system.

When the user manually retransmits the query, it can accurately reflect the user's intention, but there is still a difficulty in selecting a keyword and it is inconvenient to retransmit.

To overcome this drawback, the search system recommends an associated query based on a user query log. The related query recommendation helps users to find the information they want easily and conveniently. However, the query query cannot be recommended by distinguishing the ambiguity of the query. There are two ways to display the results automatically and personalized systematically, to re-rank the search results for each user and to expand the first query to the user's profile.

Both methods can increase the accuracy and convenience of a single keyword transmission to get exactly the results the user wants, but personalized results can be confusing to users. For example, a search system may show the results of a document about "biological virus" at the top because the user's preference information is a biological virus, or expand the query term related to a biological virus. If you try to find a document related to ”, it is rather confusing.

In order to display these personalized search results, each user's personal information using a search engine must be stored in a server. However, such a search system increases the risk that personal privacy may be breached.

Accordingly, the technical problem of the present invention is to solve such a conventional problem, and an object of the present invention is to eliminate the risk of privacy infringement when providing a personalized search result to recommend a query to a user based on a folkson for a personalized search. To provide a personalized web-based search method.

In addition, another object of the present invention is to provide a system for performing the above-described method of personalized web search.

In order to realize the above object of the present invention, in the method of personalized web search based on Foxonomy, the server collects tag data on the Internet and analyzes the collected tag data by clustering the URL number and the URL. Storing the information, and when the client transmits the bookmarked URL to the server, generating and storing the tag information and the user profile in the cluster with the data received from the server, and the search engine of the server. And transmitting the corresponding query word and user profile information about the query word to the server, and analyzing the user profile information to display an associated search word suitable for the user.

In the present embodiment, in the folksonomy analysis, the correlation value indicating the degree of association between the URL and the tag is expressed by the following equation, using TF-IDF weights.

Can be calculated by

In the present embodiment, in order to store the clustering information, the similarity between URLs may be calculated by using a cosine similarity formula, and clustering may be performed by distinguishing URLs having high association values.

In the present embodiment, the step of analyzing the user profile information and showing the relevant search query suitable for the user, leveling the association value so that the association value of all tags in the cluster has a constant value regardless of the number of bookmarks of the URL. Calculate the leveling value, multiply the ratio of URLs containing the tag in the cluster by the leveling value to increase the relevance value of the tags that are most important in the cluster, To recommend the tag, a tag having a high value calculated by multiplying the value of the number of times a user bookmarks in the cluster by the ratio of the URL multiplied by the leveling value may be recommended as the related search word.

In the present embodiment, the URL information bookmarked by the user includes a URL address bookmarked on a deliberate site or the user's local computer, and the data received from the server is a cluster number including the corresponding URL, a cluster number of the URL. It may include a tag list of the cluster.

In the present embodiment, the user profile information may include a cluster number and a URL number bookmarked in the cluster.

In order to realize the above object of the present invention, a folkson-based personalized web search system according to an embodiment includes a server and a client. The server collects tag data on the Internet, performs a folksonomy analysis on the collected tag data, and stores clustering information including the URL number and the URL. The client transmits a URL bookmarked by the user to the server, generates and stores tag information and a user profile in the cluster with the received data according to the response, and the query and the query as the user inputs the query. The user profile information for is transmitted to the search engine of the server, and the related search word suitable for the user is received and displayed based on the user profile information analyzed by the server.

In the present embodiment, the server, when analyzing the folksonomy, by using the TF-IDF weight associative value indicating the degree of association between the URL and the tag, the following equation,

Can be calculated by

In this embodiment, the server, in order to store the clustering information,

The similarity between URLs can be calculated through cosine similarity formula, and clustering can be performed by distinguishing URLs with high association values.

In this embodiment, the server analyzes the user profile information to show the relevant search query suitable for the user, so that the association value of all the tags in the cluster has a constant value regardless of the number of bookmarks of the URL. Equalize the value by calculating the leveling value, multiply the leveling value by the percentage of URLs containing the tag in the cluster to increase the relevance value of the most important tag in the cluster, In order to recommend clusters, tags having a high value calculated by multiplying a value of the number of times a user bookmarks in a cluster by the ratio of the URL multiplied by the leveling value may be recommended as the related search word.

In the present embodiment, the server may store the clustering information except for the user ID field.

In the present embodiment, the URL information bookmarked by the user includes a URL address bookmarked from a Delicious site or a user's local computer, and the data received from the server includes a cluster number including the corresponding URL, a cluster number of URLs. Number, tag list of the cluster may be included.

In the present embodiment, the user profile information may include a cluster number and a URL number bookmarked in the cluster.

According to such a method of personalized web search and a system for performing the same, a personalized search is possible and a privacy problem is solved, and a search engine service company can provide an efficient system architect that can utilize user profile information. In addition, it is possible to implement a system that recommends a query by using data from a del.icio.site site that provides a Foxonomy service for personalized search.

1A to 1C are conceptual views for explaining an effect of a user model component on a search system.
2 is a graph illustrating a relationship between the number of bookmarked users and the number of URLs.
3 is a graph showing the number of times a tag is used by a Delicious Site user.
4 is a block diagram illustrating a personalized search service procedure according to the present invention.
5 is a flowchart illustrating a method for personalized web search based on folksonomy according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in more detail with reference to the accompanying drawings. As the inventive concept allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. Singular expressions include plural expressions unless the context clearly indicates otherwise.

In this application, the terms "comprises", "having", and the like are used to specify that a feature, a number, a step, an operation, an element, a part or a combination thereof is described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

Also, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Next, the vector space model, Folksonomy and personalized search related to the present invention will be briefly described.

Vector space model

The vector space model is an algebraic model that represents a text document as a vector of index terms. In order to make good use of the vector space model, studies on the use of various methodologies and actual application results have been conducted. Among the various methods, the method used in the present invention is as follows.

,

) 사이의 코사인 각도를 아래의 수학식 1을 이용한다. As a method for determining the similarity between two documents, a vector of index words in two documents d1 and d2 (

,

Using the cosine angle between the following equation (1).

[Equation 1]

)는 간단히 문서에 색인 단어가 포함되었는지의 유무로도 판단할 수 있다. 하지만, 보다 정확한 유사도 판단을 위해 문서에 포함된 어떤 단어가 문서 내에서 얼마나 중요한 정도를 나타내는 TF-IDF 가중치를 사용하였다. 상기한 TF-IDF 가중치는 정보 검색과 텍스트 마이닝에서 이용하는 가중치로서, 여러 문서들로 이루어진 문서군이 있을 때, 어떤 단어가 특정 문서내에서 얼마나 중요한 것인지를 나타내는 통계적 수치이다. 상기한 TF-IDF 가중치는 문서의 핵심어를 추출하거나, 검색엔진에서 검색 결과의 순위를 결정하거나, 문서들 사이의 비슷한 정도를 구하는 등의 용도로 사용할 수 있다. 상대적으로 큰 TF-IDF 가중치를 갖는 단어는 더 중요하다고 볼 수 있다. 문서 d에서 등장한 단어 i의 TF-IDF 가중치는 아래의 수학식 2에 의해 산출된다. Where the weights (

) Can also be determined simply by the presence or absence of index words in the document. However, for more accurate similarity judgment, we used the TF-IDF weight which indicates how important a word included in the document is in the document. The TF-IDF weight is a weight used in information retrieval and text mining, and is a statistical value indicating how important a word is in a particular document when there is a document group composed of several documents. The TF-IDF weight may be used to extract key words of a document, to rank search results in a search engine, to obtain a similar degree between documents, and the like. Words with relatively large TF-IDF weights are more important. The TF-IDF weight of the word i appearing in the document d is calculated by Equation 2 below.

[Equation 2]

는 IDF(Inverse Document Frequency)에 해당하며, 문서 집합내에서 해당 단어가 포함된 문서의 빈도수의 역수를 뜻한다. IDF의 의미는 문서와 연관된 단어일수록 많은 문서들에서 적게 사용되는 것을 나타낸다. Here, tfi corresponds to TF (Term Frequency), and means the frequency of a specific word in the document. The meaning of TF indicates that the words that appear in the document are important in the document. Also,

Corresponds to Inverse Document Frequency (IDF), and means the inverse of the frequency of the document including the word in the document set. The meaning of IDF means that the word associated with a document is used less in more documents.

Foxsonomy ( Folksonomy )

Foxsonomy is a new classification system that divides by tags instead of the directory, which is the traditional classification standard, which means "classification by people." The difference from Foxonomy's existing classification system is that members voluntarily give unit information meaning by organizing unit information.

Popular sites that provide such services include del.icios.us, a bookmark sharing site, and flicker, an online photo sharing site. When users of the site voluntarily bookmark or store URLs or image files that are of interest to the user, they add meaning to the web document or image file by creating a tag associated with the web document or image. The tags created by the plurality of users may be used as classification criteria of web documents or images. Various studies have been conducted using tag data, which is the standard for such folksonomy, in personalized search.

Personalized search

Identifying the user's characteristics through the user's behavioral information, such as sending pages selected by the user and sending query terms, is called user modeling (or profiling) technology. It is called. In addition, a search system component that affects a search result by using a user profile in the search system is called a user model component, and affects three different aspects as described below with reference to FIGS. 1A, 1B, and 1C.

1A to 1C are conceptual views for explaining an effect of a user model component on a search system.

FIG. 1A shows a personalized search result suitable for each user by using a user profile for a query sent by a user. Responsiveness is faster than in FIGS. 1B and 1C, but consumes longer time compared to the Non-Personalized IR technique.

FIG. 1B readjusts the recommendation order of documents according to the user profile, and may increase the precision of the search result according to the user. Most reranking retrieval systems are implemented on the client to reduce the time spent on privacy problems and reranking.

FIG. 1C is a modification of a query in most clients to reduce the additional overhead of downloading multiple documents for personalization into a search system that modifies a query through a user's profile. Most search systems for personalization require additional overhead to show results tailored to each user and have been implemented on the client to reduce this overhead and prevent privacy intrusion. However, these retrieval systems have a disadvantage that a service provider that does not provide various personalization services using user profile information.

Hereinafter, a description will be given of a method of generating a user profile using Foxson and a search system that can reduce the additional overhead and privacy threats generated by the personalized search system through the user profile and also utilize the user's profile information.

If the user profile can be generated by analyzing the folksonomy, the user model component in the personalized search system can use the user profile to show personalized search results. Accordingly, the present invention proposes a user profile generation method and a personalized search method using a user profile for use in a personalized search.

Foxsonomy  analysis

Delicious sites created by users provide information to classify tags associated with the web document content of a URL. To use this data as a user profile, the following assumptions were made.

In addition, the user's bookmarking data is based on the date that the URL was bookmarked (Date), the user ID that bookmarked the URL, the URL address of the web document, and the user's bookmarking document. It includes the word tag, and the details are as follows.

With this bookmarking data, the tags that many users choose as the criteria for classifying documents in a URL are highly relevant to the URL, and to express the association between the URL and the tag, m A matrix M of size n was generated. Where m is the number of all tags and n is the number of all URLs. The association value M _ij representing the degree of association of the URL with the tag can also be expressed simply as the number of users bookmarked with tag i for URL _j .

However, in the present invention, in order to increase the accuracy of the association value (M _ij ) of the URL and the tag, it is calculated by using Equation 3 below using TF-IDF (Term Frequency-Inverse Document Frequency) weight. In general, the TF-IDF weight is a weight used in information retrieval and text mining, and it is a statistical value indicating how important a word is in a particular document when there is a document group composed of several documents. It can be used to extract key words of a document, to rank search results in a search engine, or to obtain a degree of similarity between documents. Words with relatively large TF-IDF weights are more important.

&Quot; (3) "

Here, U _ij corresponds to TF (frequency of specific words in the document) in TF-IDF. For example, if 10,619 people were facebooked to the www.facebook.com site and 10,083 users were tagged with the tag "social," the TF values would be 10,619 and 10,083, respectively.

However, this TF value becomes a problem in view of the actual number of bookmarking sites.

2 is a graph illustrating a relationship between the number of bookmarked users and the number of URLs.

Referring to FIG. 2, 80% of URLs bookmarked by less than 100 people for any 50,000 page URLs occupy 80%, and this ratio is similar in the entire URL.

Therefore, a problem arises in that the association value (M _ij ) of URLs and tags tagged by a plurality of users becomes large. In order to solve such a problem, a method of dividing the URL by the number of all bookmarked users can be used. have. However, this deformation causes other problems.

3 is a graph showing the number of times a tag is used by a Delicious Site user.

In FIG. 3, the X axis represents tags used by the users and the Y axis represents the number of uses of the tags. As can be seen in Figure 3, the tag utilization behavior of the user has a long-tail (long-tail) appearance. The number of words that more than 1,000 people used as tags was 28,097, and the number of words that less than 1,000 people used as tags was about 120,000.

In the tag located at the tail of the long tail, there are a plurality of tags that use the user's ID, typos, meaningless symbols, etc., and these tags have a large error in the search system when used for query expansion, recommendation, and reranking. Can cause.

Therefore, in order to solve the case where a tag that is not related to the URL has a high degree of association in a URL having a small number of bookmarked users, the normalization of the association value M _ij is applied in the process of recommending a personalized association keyword.

In addition, in order to obtain an inverse document frequency (IDF) value, the number of URLs including tags and the total number of URLs should be obtained. The difference may vary depending on the method of collecting URLs and the total amount of URL data collected. Here, the IDF value is an inverse of the DF (document frequency) value. The IDF value depends on the nature of the document family. For example, the word <atomic> is not likely to appear well among ordinary documents, so the IDF value is high and can be a key word of the document.However, in the case of a group of documents that contain atoms, the word becomes a common word. Other words that can be broken down into segments get high weights.

Therefore, the IDF value is not calculated as the value of the URL including the corresponding URL among the entire URLs, and the number of times the specific bookmark is tagged and the specific tag so that the weight can be calculated based on the number of bookmarks of the tag accurately provided by the delicious site. Was transformed to the number of times used to bookmark the URL, and the correlation value (M _ij ) was calculated as shown in Equation 4 below.

&Quot; (4) &quot;

값은 해당 URL을 북마킹한 횟수가 가장 높은 태그를 구하기 위한 TF값이 되며,

값은 전체 URL들을 북마킹하기 위하여 자주 사용되는 태그가 아닌 특정 URL에서만 자주 사용되는 태그를 구분하기 위한 IDF값이 된다. Therefore, the relevance value M _ij is a weight value for distinguishing a URL using the TF-IDF weight for obtaining the word most relevant to the document and the tag most related to the document.

The value is the TF value to get the tag with the highest number of bookmarks for that URL.

The value is not an tag that is often used to bookmark entire URLs, but rather an IDF value that identifies a tag that is often used only in a particular URL.

Hierarchical Clustering

Looking at the relationship between tags and URLs on the Delicious site, URLs with similar concepts consist of highly related tags, and URLs with highly related tags were URLs with similar concepts. Also, the words used as the criteria for classifying documents of the URL by users are often used as query words for searching the document in a search engine.

Therefore, if a tag having a high relevance value (M _ij ) among the tags of a URL that is highly related to the query is recommended as an associated query, it will be an effective recommendation. In order to recommend such a related search word, a process of first classifying highly related URLs and clustering them is required. In order to cluster highly relevant URLs, the similarity between URLs was calculated using the cosine similarity formula as shown in Equation 5 below.

[Equation 5]

Based on this similarity, URLs were clustered using a hierarchical agglomerative clustering algorithm.

As can be seen in Figure 3, in general, the number of important tags used by a plurality of users is much less than the number of less important or meaningless tags used by a few users. Therefore, if the entire tag vector is used for the cosine similarity calculation, a similar URL but a low similarity value may appear.

In order to increase the accuracy of the similarity, the embodiment of the present invention uses only the top 20 tags of each URL.

In addition, since most URLs have a small number of bookmarks, the number of tags included in the URL is small (see FIG. 2). Therefore, in order to correct the similarity of these URLs, when there are three or more higher-ranked tags in each URL, the similarity value between the two URLs is increased. Even when the similarity is low, a value below the threshold restricts clustering to prevent clustering.

Based on this, as shown in Table 1 below, data consisting of clustering information of URLs was generated, and as shown in Table 2 below, data consisting of tag information included in the corresponding cluster was generated. The data was saved in an inverted file format for speed of retrieval, and the URL number indicates the number of URLs included in the cluster.

TABLE 1

TABLE 2

Create user profiles and personalize search suggestions

User profile information storing bookmarking information of each user based on cluster data is generated as shown in Table 3. The user profile information indicates a URL bookmarked by each user and clustering information to which the URL belongs.

TABLE 3

Using the user profile information of Table 3, the following simple method may be used to recommend a personalized search word.

However, there may be some problems when using this method as it is. A tag used by a very small number of users that is not significantly related to the URL may have a high weight on a URL with a small number of bookmarked users, and the tag may be recommended. In order to solve this problem, the correlation value (M _ij ) of all the tags in the cluster is equalized as shown in Equation 6 below to have a constant value irrespective of the number of bookmarks of the URL.

&Quot; (6) &quot;

Where m is the number of URLs in the cluster.

In order to increase the association value (M _ij ) of the most important tag in the cluster, Equation 6 is multiplied by the ratio of URLs including the tag in the cluster as shown in Equation 7 below.

[Equation 7]

Here, U (tag) is the number of URLs including a tag.

This method solves the problem of recommending highly important queries in a cluster. However, since the actual query word can be included in several clusters, the weight value in each cluster must be different.

Therefore, in order to recommend the URLs bookmarked by the user in the cluster order, the value of the number of times the user bookmarked the cluster in the cluster is multiplied by the equation (7).

[Equation 8]

Here, C is the number of times each user bookmarked a URL in the cluster.

If a tag with a high value of Equation 7 is recommended among the tags of the cluster including the query sent by the user, the result of the personalized search term recommendation will be shown according to the URL bookmarked by the user. In the present invention, the top five tags having the highest association with the query word transmitted by the user are recommended according to Equation 7, and a threshold value is set to prevent the recommendation of a tag having a too low value.

When a user who bookmarks a URL (http://maxthon.com/download.htm, http://icab.de) belonging to the same cluster through the previous method transmits the query word "internet" The results of related search terms that are recommended are shown in <Table 4>.

TABLE 4

The above result suggests tags representing a cluster including a URL of interest to the user according to Equation 8. However, in this method, tags representing only URLs bookmarked by each user may have an important meaning to the user who sent the query, but are not recommended as related search terms because the value is lowered by Equation 8.

Therefore, the top 10 tags with high relevance value (M _ij ) among the user-marked URLs in the cluster were also recommended as related search terms. In this way, not only the tags representing the cluster but also the tags representing the URLs bookmarked by the user are recommended as related search terms.

TABLE 5

The results shown in Table 5 show the results of recommending related search terms to two users when two users who bookmarked different URLs in the same cluster sent the same query "browser". Since we bookmarked URLs in the same cluster, the words "software" and "web", which represent the cluster, were equally recommended, and additionally, related search terms representing the URLs bookmarked by the two users were recommended. .

To implement personalized search, user profiles must be stored on the server to provide services. However, storing user profiles on the server is a privacy threat. To solve this problem, user profile information must be stored on the client. However, if a client needs a storage space for storing all clustering information of the server, and the client provides a personalized search service, it becomes difficult for a search engine to provide a specialized service such as personalized advertisement to the user through the information.

The present invention proposes a search system configuration for solving such a problem.

4 is a block diagram illustrating a personalized search service procedure according to the present invention.

Referring to FIG. 4, the server 200 collects tag data on the Internet using a search engine 210 and performs folksonomy analysis on the collected tag data to store clustering information including a URL number and a URL (step S200). S10).

Subsequently, when the client 100 transmits the bookmarked URL to the server, the server 100 generates the tag information and the user profile in the cluster using the data received from the server 200 (step S20).

Subsequently, when the client 100 transmits the query to the search engine 210, the user 100 also transmits user profile information about the query (step S30).

Subsequently, the server 200 analyzes the user profile information and shows relevant search terms suitable for the user (step S40).

As such, the server 200 collects tag data on the Internet and performs folksonomy analysis on the collected tag data to store clustering information including the URL number and the URL. Meanwhile, the client 100 transmits the URL marked by the user to the server 200, generates and stores tag information and a user profile in the cluster with the received data according to the response, and the user inputs a query. As a result, the query and the user profile information on the query are transmitted to the search engine 210 of the server 200, and the related search word suitable for the user is received and displayed based on the user profile information analyzed by the server. .

According to the personalized search service procedure described in FIG. 4, the user profile should be stored in the client because the user profile information should be transmitted together with the query word.

To this end, the following describes a space for storing a user profile in a client and a method of generating a user profile, and a method of transmitting a user profile together with a query word and an overhead due to the transmission.

In order to collect, analyze, and store tag information in the clients of [Table 1], [Table 2], and [Table 3], performance problems and storage space problems may occur. Therefore, the data in [Table 1] is collected, analyzed and stored in the server, and the data in [Table 2] and [Table 3] are stored only in the client through the communication with the server. The problem of space can be solved.

The size of data for storing tag information (for example, shown in Table 2) in a cluster including a URL bookmarked by a user may be defined by Equation 9 below.

[Equation 9]

Assuming that the average size of the word is 10 bytes, the cluster number is 4 bytes, and the number of tags in the cluster is about 100, on average, one clustering information is required to store about 1.4 kilobytes (KB). If a user is interested in 10,000 clusters, they use about 14 megabytes (MB) of storage.

In the data for storing the user profile (for example, shown in Table 3) in the client, information except for the user ID field is stored, and the size may be defined by Equation 10 as follows.

[Equation 10]

As in the previous assumption, if there are 10,000 clusters of interest to users and bookmarked an average of 10 URLs per cluster, storage of approximately 800KB is assumed assuming that the cluster number size is 4 bytes and the URL number size is 4 bytes. Use space Thus, a capacity of about 15 MB is needed to store the entire user profile (assuming 100,000 bookmarking URL information and about one million words of information).

5 is a flowchart illustrating a method for personalized web search based on folksonomy according to the present invention.

In the present invention, the data is stored in the DB, and the process for generating the data is the same as in step S110, step S120, and step S130 of FIG. 5.

After sending the client's own basic bookmarking information (e.g., a bookmarked URL address of the Delicious site or a URL address bookmarked from the user's local computer) to the server (step S110), the server is configured to include the cluster containing the URL. Obtain the number, the number in the cluster of the URL, the tag list of the cluster (step S120), and transmit the cluster number including the obtained URL, the cluster number of the URL, and the tag list of the cluster as a response result to the client. . This process is driven by the user's choice of personalized search, as a result of which the client creates a user profile. Based on user profile created once, it is continuously used for personalized search.

In addition, as previously described, user profiles are transmitted along with the query, resulting in transmission overhead. The query transmission process is the same as step S210, step S220, and step S230 of FIG.

After generating the user profile based on the response result (step S210), the client searches whether the query is a word included in the cluster of interest to the user, and if the word is included, information of the related user profile (for example, The cluster number and the bookmarked URL number in the cluster) are transmitted to the server (step S220).

Assuming that one query is included in four clusters and that the average number of bookmarked URLs in one cluster is 10, the additional information to be transmitted when transmitting a query is cluster number (4 bytes) × 4 and URL number (4 bytes) × It takes about 56 bytes, which is 10. The more URLs bookmarked, the larger the size required for transmission. Therefore, if clustering includes up to 32 URLs per cluster in order to reduce such overhead, 32 URL numbers can be expressed in bits by 4 bytes.

The server recommends the relevant search word most suitable for the user through the personalized search recommendation method with the query word received from the client and the user's profile information (step S230). However, using only the profile created once for personalized search does not show proper personalized search result when user's preference changes over time.

Therefore, the server transmits the cluster number and the URL number of the document selected by the user as shown in steps S310, S320, and S330 of FIG. 5, so that the user can create an updated user profile based on this information if desired. have.

That is, as the client clicks stream (step S310), the server transmits the cluster number and URL number for the document to the client (step S110), whereby the client generates an updated user profile (step S330).

Experiment result

Finally, through the proposed method, we set up a hypothetical user who has bookmarked 10 pages related to fashion blogs and music blogs, and search results related to Google and Yahoo search terms. Compared with

Table 6 shows the related search term recommendation results in Google.

TABLE 6

Table 7 shows related search word recommendation results in Yahoo.

<Table 7>

Based on the results shown in Table 6 and Table 7, it is assumed that the related search word recommendation method is recommended through the user's search log, such as a query used by a plurality of users. In the case of Yahoo, we can see that some algorithms have recommended additional words of related concepts. However, both results did not show personalized results because they did not know what the user meant. Instead, they suggested related search terms on various topics related to various blogs.

Table 8 is a result of recommendation of the relevant search word of the personalized search system proposed in the present invention.

Suppose a user bookmarked a blog about fashion (5 top URLs) and food (5 top URLs) and suggested a related search term. It can be seen from Table 8 that the method according to the present invention can know the user's preferred information through the user profile and recommends the relevant related search word to the user.

Although described above with reference to the embodiments, those skilled in the art can be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below. I can understand.

As described above, according to the present invention, a personalized search is possible, a privacy problem is solved, and a search engine service company can implement an efficient search system architecture that can utilize user profile information. A search system that recommends a query can be implemented using data from a del.icio.us site that provides a Foxonomy service for personalized search. The search system architecture according to the present invention can be applied not only to re-ranking and extension of a query for personalized search, but also to a search system that recommends personalized tags.

A user profile may be generated using tag data generated by a plurality of users, and a personalized related search term may be displayed using the generated user profile information.

In addition, in order to solve the problem caused when the user profile information is stored only in either the server or the client, the present invention reduces the user's privacy threat, while the server provides a personalized service using the user's profile information. Can be.

The related search term recommendation method proposed in the present invention does not reflect all of the query terms that are an issue by a plurality of users in the search engine. However, if the user's query is additionally recommended by analyzing the query log through the transmitted user profile, a better related search term recommendation result will be shown.

In the present invention, the implementation of a personalization system focusing on the recommendation of related search terms so that simple and clear results can be seen. However, it can also be used for services such as query expansion, re-ranking search results, and personalized ads. It can also be used as a system architecture for tag recommendation.

100: client 200: server
210: search engine

Claims (13)

Collecting tag data on the Internet and performing Foxson analysis on the collected tag data to store clustering information including a URL number and a URL;
When the client transmits the bookmarked URL to the server, generating and storing tag information and a user profile in the cluster using the data received from the server;
Transmitting the query term and user profile information on the query term to a search engine of the server; And
And the server analyzing the user profile information and displaying a related search term suitable for the user. The method of claim 1, wherein in the folksonomy analysis, the correlation value indicating the degree of association between the URL and the tag is expressed by the following equation, using TF-IDF weights.

Foxonomi based personalized web search method, characterized in that calculated by. The method of claim 1, in order to store the clustering information.
A phosonomi based personalized web search method characterized by calculating similarity between URLs through cosine similarity formula and clustering by distinguishing URLs having high association value. The method of claim 1, wherein the analyzing the user profile information and displaying a related search term suitable for a user comprises:
The leveling value is calculated by leveling the degree of relevance so that the relevance value of all tags in the cluster has a constant value regardless of the number of bookmarks of the URL.
In order to increase the affinity value of the most important tag in the cluster, the leveling value is multiplied by the ratio of URLs containing the tag in the cluster,
In order to recommend the clusters in which the URLs are bookmarked by the user in the order of clusters, the tags having the high value calculated by multiplying the value of the URLs multiplied by the leveling value by the ratio of the number of bookmarks in the cluster are related to the related search terms. Foxonomy-based personalized web search method characterized in that the recommended as. The method of claim 1, wherein the URL information bookmarked by the user includes a URL address bookmarked on a deliberate site or a user's local computer, and the data received from the server includes a cluster number including the URL, a cluster number of URLs. Foxonomy-based personalized web search method comprising a number, the list of tags of the cluster. The method of claim 1, wherein the user profile information comprises a cluster number and a bookmarked URL number in the cluster. A server that collects tag data on the Internet and analyzes the collected tag data to store clustering information including a URL number and a URL; And
The user sends the bookmarked URL to the server, generates and stores tag information and a user profile in the cluster with the received data according to the response, and the user for the query and the query as the user inputs the query. And a client configured to transmit profile information to a search engine of the server and to receive and display a relevant search word suitable for a user based on the user profile information analyzed by the server. The method of claim 7, wherein the server uses the TF-IDF weight to determine an association value indicating a degree of association between a URL and a tag in the folksonomy analysis.

Foxonomi based personalized web search system, characterized in that calculated by. The method of claim 7, wherein the server, in order to store the clustering information,
A phosonomi based personalized web retrieval system characterized by calculating similarity between URLs through cosine similarity formula and clustering by distinguishing URLs having high association value. The method of claim 7, wherein the server analyzes the user profile information and displays relevant search terms suitable for a user.
The leveling value is calculated by leveling the degree of relevance so that the relevance value of all tags in the cluster has a constant value regardless of the number of bookmarks of the URL.
In order to increase the affinity value of the most important tag in the cluster, the leveling value is multiplied by the ratio of URLs containing the tag in the cluster,
In order to recommend the clusters in which the URLs are bookmarked by the user in the order of clusters, the tags having the high value calculated by multiplying the value of the URLs multiplied by the leveling value by the ratio of the number of bookmarks in the cluster are related to the related search terms. Foxonomi based personalized web search system, characterized in that recommended as. The system of claim 7, wherein the server stores the clustering information excluding the user ID field. 8. The method of claim 7, wherein the URL information bookmarked by the user includes a URL address bookmarked from a deliberate site or a user's local computer, and the data received from the server includes a cluster number including the corresponding URL and a cluster of URLs. Foxonomy-based personalized web search system comprising a number list, the tag list of the cluster. The system of claim 7, wherein the user profile information comprises a cluster number and a URL number bookmarked in the cluster.

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