-
Ingwersen, P.; Willett, P.: ¬An introduction to algorithmic and cognitive approaches for information retrieval (1995)
0.01
0.012319634 = product of:
0.0369589 = sum of:
0.0369589 = weight(_text_:on in 4344) [ClassicSimilarity], result of:
0.0369589 = score(doc=4344,freq=6.0), product of:
0.109763056 = queryWeight, product of:
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.04990557 = queryNorm
0.33671528 = fieldWeight in 4344, product of:
2.4494898 = tf(freq=6.0), with freq of:
6.0 = termFreq=6.0
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.0625 = fieldNorm(doc=4344)
0.33333334 = coord(1/3)
- Abstract
- This paper provides an over-view of 2, complementary approaches to the design and implementation of information retrieval systems. The first approach focuses on the algorithms and data structures that are needed to maximise the effectiveness and the efficiency of the searches that can be carried out on text databases, while the second adopts a cognitive approach that focuses on the role of the user and of the knowledge sources involved in information retrieval. The paper argues for an holistic view of information retrieval that is capable of encompassing both of these approaches
-
Ekmekcioglu, F.C.; Robertson, A.M.; Willett, P.: Effectiveness of query expansion in ranked-output document retrieval systems (1992)
0.01
0.012319634 = product of:
0.0369589 = sum of:
0.0369589 = weight(_text_:on in 5689) [ClassicSimilarity], result of:
0.0369589 = score(doc=5689,freq=6.0), product of:
0.109763056 = queryWeight, product of:
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.04990557 = queryNorm
0.33671528 = fieldWeight in 5689, product of:
2.4494898 = tf(freq=6.0), with freq of:
6.0 = termFreq=6.0
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.0625 = fieldNorm(doc=5689)
0.33333334 = coord(1/3)
- Abstract
- Reports an evaluation of 3 methods for the expansion of natural language queries in ranked output retrieval systems. The methods are based on term co-occurrence data, on Soundex codes, and on a string similarity measure. Searches for 110 queries in a data base of 26.280 titles and abstracts suggest that there is no significant difference in retrieval effectiveness between any of these methods and unexpanded searches
-
Furner-Hines, J.; Willett, P.: ¬The use of hypertext in libraries in the United Kingdom (1994)
0.01
0.009239726 = product of:
0.027719175 = sum of:
0.027719175 = weight(_text_:on in 5383) [ClassicSimilarity], result of:
0.027719175 = score(doc=5383,freq=6.0), product of:
0.109763056 = queryWeight, product of:
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.04990557 = queryNorm
0.25253648 = fieldWeight in 5383, product of:
2.4494898 = tf(freq=6.0), with freq of:
6.0 = termFreq=6.0
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.046875 = fieldNorm(doc=5383)
0.33333334 = coord(1/3)
- Abstract
- State of the art review of hypertext systems in use in UK libraries. Systems include public access point of information (POI) systems that provide guidance to users of local resources, and networked document retrieval systems, such as WWW, that enable users to access texts stored on machines linked by the Internet. Particular emphasis is placed on those systems that are produced inhouse by the libraries in which they are used. The review is based on a series of telephone or face to face interviews conducted with representatives of those organizations that a literature review and mailed questionnaire survey identified as current users of hypertext. Considers issues relating to system development and usability, and presents a set of appropriate guidelines for the designers of future systems. Concludes that: the principle application of hypertext systems in UK libraries is in the implementation of POI systems; that such development is most advanced in the academic sector; and that such development is set to increase in tandem with use of the WWW
-
Shaw, R.J.; Willett, P.: On the non-random nature of nearest-neighbour document clusters (1993)
0.01
0.007112743 = product of:
0.021338228 = sum of:
0.021338228 = weight(_text_:on in 5817) [ClassicSimilarity], result of:
0.021338228 = score(doc=5817,freq=2.0), product of:
0.109763056 = queryWeight, product of:
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.04990557 = queryNorm
0.19440265 = fieldWeight in 5817, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.0625 = fieldNorm(doc=5817)
0.33333334 = coord(1/3)
-
Robertson, A.M.; Willett, P.: Identification of word-variants in historical text databases : report for the period October 1990 to September 1992 (1994)
0.01
0.007112743 = product of:
0.021338228 = sum of:
0.021338228 = weight(_text_:on in 939) [ClassicSimilarity], result of:
0.021338228 = score(doc=939,freq=2.0), product of:
0.109763056 = queryWeight, product of:
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.04990557 = queryNorm
0.19440265 = fieldWeight in 939, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.0625 = fieldNorm(doc=939)
0.33333334 = coord(1/3)
- Abstract
- Databases of historical texts are increasingly becoming available for end user searching via online or CD-ROM databases. Many of the words in these databases are spelt differently from today with resultant loss of retrieval. The project evaluated a range of techniques that can suggest historical variants of modern language query words, the work deriving from earlier work on spelling correction
-
Robertson, A.M.; Willett, P.: Use of genetic algorithms in information retrieval (1995)
0.01
0.007112743 = product of:
0.021338228 = sum of:
0.021338228 = weight(_text_:on in 2418) [ClassicSimilarity], result of:
0.021338228 = score(doc=2418,freq=2.0), product of:
0.109763056 = queryWeight, product of:
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.04990557 = queryNorm
0.19440265 = fieldWeight in 2418, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.0625 = fieldNorm(doc=2418)
0.33333334 = coord(1/3)
- Abstract
- Reviews the basic techniques involving genetic algorithms and their application to 2 problems in information retrieval: the generation of equifrequent groups of index terms; and the identification of optimal query and term weights. The algorithm developed for the generation of equifrequent groupings proved to be effective in operation, achieving results comparable with those obtained using a good deterministic algorithm. The algorithm developed for the identification of optimal query and term weighting involves fitness function that is based on full relevance information
-
Robertson, M.; Willett, P.: ¬An upperbound to the performance of ranked output searching : optimal weighting of query terms using a genetic algorithms (1996)
0.01
0.007112743 = product of:
0.021338228 = sum of:
0.021338228 = weight(_text_:on in 6977) [ClassicSimilarity], result of:
0.021338228 = score(doc=6977,freq=2.0), product of:
0.109763056 = queryWeight, product of:
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.04990557 = queryNorm
0.19440265 = fieldWeight in 6977, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.0625 = fieldNorm(doc=6977)
0.33333334 = coord(1/3)
- Abstract
- Describes the development of a genetic algorithm (GA) for the assignment of weights to query terms in a ranked output document retrieval system. The GA involves a fitness function that is based on full relevance information, and the rankings resulting from the use of these weights are compared with the Robertson-Sparck Jones F4 retrospective relevance weight
-
Clarke, S.J.; Willett, P.: Estimating the recall performance of Web search engines (1997)
0.01
0.007112743 = product of:
0.021338228 = sum of:
0.021338228 = weight(_text_:on in 760) [ClassicSimilarity], result of:
0.021338228 = score(doc=760,freq=2.0), product of:
0.109763056 = queryWeight, product of:
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.04990557 = queryNorm
0.19440265 = fieldWeight in 760, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.0625 = fieldNorm(doc=760)
0.33333334 = coord(1/3)
- Abstract
- Reports a comparison of the retrieval effectiveness of the AltaVista, Excite and Lycos Web search engines. Describes a method for comparing the recall of the 3 sets of searches, despite the fact that they are carried out on non identical sets of Web pages. It is thus possible, unlike previous comparative studies of Web search engines, to consider both recall and precision when evaluating the effectiveness of search engines
-
Ellis, D.; Furner-Hines, J.; Willett, P.: On the creation of hypertext links in full-text documents : measurement of inter-linker consistency (1994)
0.00
0.0044454644 = product of:
0.013336393 = sum of:
0.013336393 = weight(_text_:on in 7493) [ClassicSimilarity], result of:
0.013336393 = score(doc=7493,freq=2.0), product of:
0.109763056 = queryWeight, product of:
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.04990557 = queryNorm
0.121501654 = fieldWeight in 7493, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.0390625 = fieldNorm(doc=7493)
0.33333334 = coord(1/3)
-
Ellis, D.; Furner, J.; Willett, P.: On the creation of hypertext links in full-text documents : measurement of retrieval effectiveness (1996)
0.00
0.0044454644 = product of:
0.013336393 = sum of:
0.013336393 = weight(_text_:on in 4214) [ClassicSimilarity], result of:
0.013336393 = score(doc=4214,freq=2.0), product of:
0.109763056 = queryWeight, product of:
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.04990557 = queryNorm
0.121501654 = fieldWeight in 4214, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
2.199415 = idf(docFreq=13325, maxDocs=44218)
0.0390625 = fieldNorm(doc=4214)
0.33333334 = coord(1/3)
