the web search engines and general reference questions

six web search engines, namely, altavista, excite, go, google, hot bot and lycos, were compared and evaluated in terms of their search capabilities (i.e., duplicate, false drops, mirror sites, dead links) and retrieval performances (i.e., precision) using sample queries drawn from real reference questions from the reference desk of the central library of shiraz university (mirzay-e-shirazi library). recall, another evaluation criterion of information retrieval, is deliberately omitted from this study; because, it is impossible to assume how many relevant items there are for a particular query in the huge and ever changing web system. the authors of this study found that google showed the best performance, although altavista had the largest coverage of web resources amongst the six web search engines examined.