In this paper we present the experiments which evaluate the effectiveness of a group of Web search engines and meta-search engines. Experimental results show that on average the performances of selected meta-search engines and search engines are very close, therefore, the claim that meta-search engines are more effective than their counterpart-Web search engines can not be supported. Another observation is that, very often, search engines and meta-search engines are doing much better with short queries than with long queries, which is surprisingly opposite to conventional information retrieval systems. It suggests that Web search services focus on short queries having very few key words probably with special efforts; however, the general search techniques they use for long queries are unsophisticated and further improvement is in demand.
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