Evaluating and comparing search engines in retrieving text information from the web

[摘要] ENGLISH ABSTRACT:With the introduction of the Internet and the World Wide Web (www), information can beeasily accessed and retrieved from the web using information retrieval systems such asweb search engines or simply search engines. There are a number of search enginesthat have been developed to provide access to the resources available on the web andto help users in retrieving relevant information from the web. In particular, they areessential for finding text information on the web for academic purposes. But, howeffective and efficient are those search engines in retrieving the most relevant textinformation from the web? Which of the search engines are more effective and efficient?So, this study was conducted to see how effective and efficient search engines are andto see which search engines are most effective and efficient in retrieving the requiredtext information from the web. It is very important to know the most effective andefficient search engines because such search engines can be used to retrieve a highernumber of the most relevant text web pages with minimum time and effort.The study was based on nine major search engines, four search queries and relevancyjudgments as relevant/partly-relevanUnon-relevant. Precision and recall were calculatedbased on the experimental or test results and these were used as basis for thestatistical evaluation and comparisons of the retrieval effectiveness of the nine searchengines. Duplicated items and broken links were also recorded and examinedseparately and were used as an additional measure of search engine effectiveness. Aresponse time was also recorded and used as a base for the statistical evaluation andcomparisons of the retrieval efficiency of the nine search engines.Additionally, since search engines involve indexing and searching in the informationretrieval processes from the web, this study first discusses, from the theoretical point ofview, how the indexing and searching processes are performed in an informationretrieval environment. It also discusses the influences of indexing and searchingprocesses on the effectiveness and efficiency of information retrieval systems in generaland search engines in particular in retrieving the most relevant text information from theweb.

[发布机构] Stellenbosch University