I am deeply indebted to Dr. Michael Berry, my major advisor, for his kind guidance and support. I also thank Dr. Susan Dumais, director of the Information Sciences Research Group at Bellcore, for her technical advice. In addition, she graciously allowed us
processofcreatingpro lesandmatchingdocumentswiththepro lesissimilartorelevancefeedback,atechniqueusedbyinformationretrievalsystemstoenrichauser’squery.RelevancefeedbackwillbediscussedinSection2.2.6.
Sinceinformation lteringmustdealwithsomeofthesameissuesasinformationretrieval(forexample,differencesinwordusage),conceptualinformationretrievalmodelsareoftenusedforinformation lteringapplications.Sofar,resultshaveindi-catedthatinformation lteringisusefulfordecreasingtheamountofinformationapersonmustconsider,whilestillprovidingtheinformationheorshemightconsideruseful[FD92].
1.3TheDevelopmentofanLSIProgrammingLibrary
Thefollowingchaptersoutlinethedevelopmentanduseofanef cient,extensible,portable,andmaintainableimplementationoftheLatentSemanticIndexingmodel.Chapter2exploresthegeneralideasbehindvector-spacemodelsforinformationre-trievalanddescribesLSIinparticular.Chapter3introducesLSI++,aC++classlibraryforsearchingwiththeLSImodel,andChapter4examineshowLSI++canbeusedtobuildbothserialanddistributedsearchengines.Inaddition,Chapter4presentsaWorld-WideWebinterfaceforLSIthatprovidesuserstheopportunitytointeractwiththeLSI++searchengines.Finally,Chapter5examinestheexecutionef ciencyofthesearchengineswrittenwithLSI++.
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