• 제목/요약/키워드: HITS Algorithm

검색결과 22건 처리시간 0.022초

웹 문서 중요도 평가를 위한 적합도 향상 HITS 알고리즘 설계 (Design of Advanced HITS Algorithm by Suitability for Importance-Evaluation of Web-Documents)

  • 김분희;한상용;김영찬
    • 한국전자거래학회지
    • /
    • 제8권2호
    • /
    • pp.23-31
    • /
    • 2003
  • 링크 기반 검색엔진은사용자의 질의어와 관련된 웹 문서들의 링크 정보를 이용하여 순위를 생성한다. 이러한 링크기반 웹 문서의 특성을 이용한 대표적인 순위 평가 알고리즘. HITS는 웹 페이지들 간의 상호 연결된 링크 정보로부터 웹 문서들의 중요도를 평가하고, 순위 정보에 따른 결과를 제시한다. 이러한 HITS 알고리즘의 문제점은 문서 내의 링크 빈도 수만을 고려하고, 입력 값으로 주어지는 웹 문서 집합의 특성에 의존적이라는 것이다. 본 논문에서는 링크기반 웹 검색 엔진들로부터 얻어진 문서 집합에 대해 질의와 검색결과 간의 적합도를 향상시킨 HITS 알고리즘을 수행하는 검색 에이전트를 설계하였다. 이로써 향상된 검객 성능과 결과의 지역성을 보완한다.

  • PDF

Sorting Instagram Hashtags all the Way throw Mass Tagging using HITS Algorithm

  • D.Vishnu Vardhan;Dr.CH.Aparna
    • International Journal of Computer Science & Network Security
    • /
    • 제23권11호
    • /
    • pp.93-98
    • /
    • 2023
  • Instagram is one of the fastest-growing online photo social web services where users share their life images and videos with other users. Image tagging is an essential step for developing Automatic Image Annotation (AIA) methods that are based on the learning by example paradigm. Hashtags can be used on just about any social media platform, but they're most popular on Twitter and Instagram. Using hashtags is essentially a way to group together conversations or content around a certain topic, making it easy for people to find content that interests them. Practically on average, 20% of the Instagram hashtags are related to the actual visual content of the image they accompany, i.e., they are descriptive hashtags, while there are many irrelevant hashtags, i.e., stophashtags, that are used across totally different images just for gathering clicks and for search ability enhancement. Hence in this work, Sorting instagram hashtags all the way through mass tagging using HITS (Hyperlink-Induced Topic Search) algorithm is presented. The hashtags can sorted to several groups according to Jensen-Shannon divergence between any two hashtags. This approach provides an effective and consistent way for finding pairs of Instagram images and hashtags, which lead to representative and noise-free training sets for content-based image retrieval. The HITS algorithm is first used to rank the annotators in terms of their effectiveness in the crowd tagging task and then to identify the right hashtags per image.

링크 구조 기반의 순위 알고리즘을 이용한 메타 검색 에이전트 (The Meta Search Agent using Ranking Algorithm with Link Structure Analysis)

  • 김형욱;김민구;최경희
    • 한국정보과학회:학술대회논문집
    • /
    • 한국정보과학회 2002년도 가을 학술발표논문집 Vol.29 No.2 (2)
    • /
    • pp.373-375
    • /
    • 2002
  • 하이퍼 텍스트 구조의 특성을 이용한 순위 평가 알고리즘 중의 하나인 HITS 알고리즘은 웹 페이지들의 상호간에 연결된 링크 정보로부터 웹 문서들의 중요도를 평가하여 순위에 따른 결과를 제시한다. 그러나 초기의 HITS 알고리즘은 문서 내의 링크 빈도 수만을 고려하고, 입력 값으로 주어지는 웹 문서 집합의 특성에 의존적인 단점을 가지고 있다. 본 논문에서는 여러 웹 검색 엔진들로부터 얻어진 문서 집합에 수정된 HITS 알고리즘을 수행하는 메타 검색 에이전트를 설계하여 보다 나은 검색 성능을 구하고, 결과의 지역성을 보완한다.

  • PDF

폭소노미 사이트를 위한 랭킹 프레임워크 설계: 시맨틱 그래프기반 접근 (A Folksonomy Ranking Framework: A Semantic Graph-based Approach)

  • 박현정;노상규
    • Asia pacific journal of information systems
    • /
    • 제21권2호
    • /
    • pp.89-116
    • /
    • 2011
  • In collaborative tagging systems such as Delicious.com and Flickr.com, users assign keywords or tags to their uploaded resources, such as bookmarks and pictures, for their future use or sharing purposes. The collection of resources and tags generated by a user is called a personomy, and the collection of all personomies constitutes the folksonomy. The most significant need of the folksonomy users Is to efficiently find useful resources or experts on specific topics. An excellent ranking algorithm would assign higher ranking to more useful resources or experts. What resources are considered useful In a folksonomic system? Does a standard superior to frequency or freshness exist? The resource recommended by more users with mere expertise should be worthy of attention. This ranking paradigm can be implemented through a graph-based ranking algorithm. Two well-known representatives of such a paradigm are Page Rank by Google and HITS(Hypertext Induced Topic Selection) by Kleinberg. Both Page Rank and HITS assign a higher evaluation score to pages linked to more higher-scored pages. HITS differs from PageRank in that it utilizes two kinds of scores: authority and hub scores. The ranking objects of these pages are limited to Web pages, whereas the ranking objects of a folksonomic system are somewhat heterogeneous(i.e., users, resources, and tags). Therefore, uniform application of the voting notion of PageRank and HITS based on the links to a folksonomy would be unreasonable, In a folksonomic system, each link corresponding to a property can have an opposite direction, depending on whether the property is an active or a passive voice. The current research stems from the Idea that a graph-based ranking algorithm could be applied to the folksonomic system using the concept of mutual Interactions between entitles, rather than the voting notion of PageRank or HITS. The concept of mutual interactions, proposed for ranking the Semantic Web resources, enables the calculation of importance scores of various resources unaffected by link directions. The weights of a property representing the mutual interaction between classes are assigned depending on the relative significance of the property to the resource importance of each class. This class-oriented approach is based on the fact that, in the Semantic Web, there are many heterogeneous classes; thus, applying a different appraisal standard for each class is more reasonable. This is similar to the evaluation method of humans, where different items are assigned specific weights, which are then summed up to determine the weighted average. We can check for missing properties more easily with this approach than with other predicate-oriented approaches. A user of a tagging system usually assigns more than one tags to the same resource, and there can be more than one tags with the same subjectivity and objectivity. In the case that many users assign similar tags to the same resource, grading the users differently depending on the assignment order becomes necessary. This idea comes from the studies in psychology wherein expertise involves the ability to select the most relevant information for achieving a goal. An expert should be someone who not only has a large collection of documents annotated with a particular tag, but also tends to add documents of high quality to his/her collections. Such documents are identified by the number, as well as the expertise, of users who have the same documents in their collections. In other words, there is a relationship of mutual reinforcement between the expertise of a user and the quality of a document. In addition, there is a need to rank entities related more closely to a certain entity. Considering the property of social media that ensures the popularity of a topic is temporary, recent data should have more weight than old data. We propose a comprehensive folksonomy ranking framework in which all these considerations are dealt with and that can be easily customized to each folksonomy site for ranking purposes. To examine the validity of our ranking algorithm and show the mechanism of adjusting property, time, and expertise weights, we first use a dataset designed for analyzing the effect of each ranking factor independently. We then show the ranking results of a real folksonomy site, with the ranking factors combined. Because the ground truth of a given dataset is not known when it comes to ranking, we inject simulated data whose ranking results can be predicted into the real dataset and compare the ranking results of our algorithm with that of a previous HITS-based algorithm. Our semantic ranking algorithm based on the concept of mutual interaction seems to be preferable to the HITS-based algorithm as a flexible folksonomy ranking framework. Some concrete points of difference are as follows. First, with the time concept applied to the property weights, our algorithm shows superior performance in lowering the scores of older data and raising the scores of newer data. Second, applying the time concept to the expertise weights, as well as to the property weights, our algorithm controls the conflicting influence of expertise weights and enhances overall consistency of time-valued ranking. The expertise weights of the previous study can act as an obstacle to the time-valued ranking because the number of followers increases as time goes on. Third, many new properties and classes can be included in our framework. The previous HITS-based algorithm, based on the voting notion, loses ground in the situation where the domain consists of more than two classes, or where other important properties, such as "sent through twitter" or "registered as a friend," are added to the domain. Forth, there is a big difference in the calculation time and memory use between the two kinds of algorithms. While the matrix multiplication of two matrices, has to be executed twice for the previous HITS-based algorithm, this is unnecessary with our algorithm. In our ranking framework, various folksonomy ranking policies can be expressed with the ranking factors combined and our approach can work, even if the folksonomy site is not implemented with Semantic Web languages. Above all, the time weight proposed in this paper will be applicable to various domains, including social media, where time value is considered important.

World Wide Web을 위한 개선된 Threshold HITS 알고리즘 (Enhanced Threshold Algorithm for HITS on the World Wide Web)

  • 김혜민;김민구
    • 한국정보과학회:학술대회논문집
    • /
    • 한국정보과학회 2004년도 가을 학술발표논문집 Vol.31 No.2 (1)
    • /
    • pp.106-108
    • /
    • 2004
  • 링크 구조를 이용하는 대표적인 알고리즘인 HITS는 링크 정보를 이용하여 Authority와 Hub rating을 구하는 알고리즘이다. 그러나 HITS에서는 중요도와는 관계없이 단순히 링크만을 많이 갖는 page의 Authority와 Hub rating이 비정상적으로 높게 계산되는 문제점이 있어 이를 해결하기 위한 연구들이 있었다. 본 논문에서는 이러한 연구들의 결과를 개선시키기 위해 Authority와 Hub rating의 단순한 합이 아닌, 평균과 priority를 적용하였다. 정확도를 측정하는 실험을 통해 제안하는 알고리즘이 기존의 방법보다 우수한 성능을 나타냄을 알 수 있다.

  • PDF

HITS알고리즘을 적용한 개념그래프 기반검색시스템의 성능개선 (Improved Concept-base Search System Using HITS algorithm on Conceptual Graph)

  • 배환국;박호성;이상준;김기태
    • 한국정보과학회:학술대회논문집
    • /
    • 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (B)
    • /
    • pp.470-472
    • /
    • 2003
  • 본 논문에서는 개념 그래프 기반 검색 시스템의 검색의 성능을 개선시키고자 Hits 알고리즘을 적용하였다. 기존 개념 그래프 기반 검색 시스템의 anchor text분석을 통하여 개념을 추출하고 있는 시스템에서 더 나아가 하이퍼 링크의 선호도의 특성을 살려 하이퍼링크에 문서가 얼마나 연결되어 있는지, 참조하고 있는지에 따라 해당 검색된 문서들의 중요도를 찾아서 순위를 매기는 실험을 하였다. 종래에는 해당 검색어의 빈도순으로 개념의 결과를 나타내 주었는데, 본 시스템 구현 후에 랭킹알고리즘을 적용하여 해당검색에 유용한 정보를 가지고 있는 페이지들(authorities)과 유용한 정보를 보유하고 있는 페이지의 링크를 보유하고 있는 페이지들(hubs)를 각각 순위 순으로 보여주게 되었다. 그리하여 사용자는 실제 검색시에 개념상으로 분류된 문서 중에 중요도가 높은 문서를 사용자에게 우선으로 접하게 되었으며, hub어 의해서 중요도가 높은 문서를 한눈에 볼 수도 있을 뿐 아니라, anchor text 어서 나타나지 않은 중요한 정보를 가진 문서도 검색할 수 있었다.

  • PDF

HITS 알고리즘을 이용한 단어 연관 관계 링크 제어 (A Link control of the word associated relation with using HITS Algorithm)

  • 문성천;이정훈;전서현
    • 한국정보과학회:학술대회논문집
    • /
    • 한국정보과학회 2010년도 한국컴퓨터종합학술대회논문집 Vol.37 No.1(C)
    • /
    • pp.395-398
    • /
    • 2010
  • 많은 정보들을 인터넷을 통하여 접할 수 있게 됨에 따라 사용자가 만족하는 결과를 보여주는 것이 검색 엔진의 궁극적인 목표가 되었다. 하지만 방대한 양을 가진 다양한 정보에서 원하는 검색 결과를 검색하는 것은 과거와 현재까지 많은 연구를 통해 많은 시간과 노력이 필요하다는 것이 증명 되었다. 기존의 HITS 알고리즘을 개선하여 링크 제어를 이용한 페이지와 페이지간에 관련성을 높였다.

  • PDF

하이퍼링크 구조를 이용한 웹 검색의 순위 알고리즘에 관한 연구 (The Study on the Ranking Algorithm of Web-based Sear ching Using Hyperlink Structure)

  • 김성희;오건택
    • 정보관리연구
    • /
    • 제37권2호
    • /
    • pp.33-50
    • /
    • 2006
  • 본 연구에서는 하이퍼 링크 구조를 이용한 웹 검색 알고리즘에 대해 살펴 본 후 페이지 품질을 측정하기 위해 웹의 하이퍼 구조를 이용하고 있는 알고리즘인 HITS와 PageRank를 분석하였다. 이어서 이들 방법을 이용한 검색 엔진인 Google과 Ask.com을 검색 알고리즘의 특성을 기준으로 분석하였다. 이런 연구는 미래의 웹 문서의 중요도를 평가하는 데 기초자료로 활용할 수 있으며, 웹 정보검색의 검색성능을 향상시키는 시스템 개발에 도움이 될 수 있을 것이라 생각한다.

Performance Comparison of Two Gene Set Analysis Methods for Genome-wide Association Study Results: GSA-SNP vs i-GSEA4GWAS

  • Kwon, Ji-Sun;Kim, Ji-Hye;Nam, Doug-U;Kim, Sang-Soo
    • Genomics & Informatics
    • /
    • 제10권2호
    • /
    • pp.123-127
    • /
    • 2012
  • Gene set analysis (GSA) is useful in interpreting a genome-wide association study (GWAS) result in terms of biological mechanism. We compared the performance of two different GSA implementations that accept GWAS p-values of single nucleotide polymorphisms (SNPs) or gene-by-gene summaries thereof, GSA-SNP and i-GSEA4GWAS, under the same settings of inputs and parameters. GSA runs were made with two sets of p-values from a Korean type 2 diabetes mellitus GWAS study: 259,188 and 1,152,947 SNPs of the original and imputed genotype datasets, respectively. When Gene Ontology terms were used as gene sets, i-GSEA4GWAS produced 283 and 1,070 hits for the unimputed and imputed datasets, respectively. On the other hand, GSA-SNP reported 94 and 38 hits, respectively, for both datasets. Similar, but to a lesser degree, trends were observed with Kyoto Encyclopedia of Genes and Genomes (KEGG) gene sets as well. The huge number of hits by i-GSEA4GWAS for the imputed dataset was probably an artifact due to the scaling step in the algorithm. The decrease in hits by GSA-SNP for the imputed dataset may be due to the fact that it relies on Z-statistics, which is sensitive to variations in the background level of associations. Judicious evaluation of the GSA outcomes, perhaps based on multiple programs, is recommended.

사회 연결망 분석 기반 자료포락분석 순위 결정 기법간 비교와 한계 극복 방안에 대한 연구 (Comparison between Social Network Based Rank Discrimination Techniques of Data Envelopment Analysis: Beyond the Limitations)

  • 강희재
    • 한국IT서비스학회지
    • /
    • 제22권1호
    • /
    • pp.57-74
    • /
    • 2023
  • It has been pointed out as a limitation that the rank of some efficient DMUs(decision making units) cannot be discriminated due to the relativity nature of efficiency measured by DEA(data envelopment analysis), comparing the production structure. Recently, to solve this problem, a DEA-SNA(social network analysis) model that combines SNA techniques with data envelopment analysis has been studied intensively. Several models have been proposed using techniques such as eigenvector centrality, pagerank centrality, and hypertext induced topic selection(HITS) algorithm, but DMUs that cannot be ranked still remain. Moreover, in the process of extracting latent information within the DMU group to build effective network, a problem that violates the basic assumptions of the DEA also arises. This study is meaningful in finding the cause of the limitations by comparing and analyzing the characteristics of the DEA-SNA model proposed so far, and based on this, suggesting the direction and possibility to develop more advanced model. Through the results of this study, it will be enable to further expand the field of research related to DEA.