ERIC Number: ED051863
Record Type: RIE
Publication Date: 1971-Mar
Reference Count: 0
The Effect of Indexing Specificity on Retrieval Performance.
The main purpose of the experiment was to answer the question whether broad or narrow terms function most effectively in the retrieval of relevant documents. The answer depends on what the user of the retrieval system wants, his wants being expressed in terms of stated precision-recall preference, or by the exact number of relevant documents he wishes to retrieve. Depth of indexing does not contribute significantly to effective retrieval. Documents should be indexed with broad terms to satisfy recall preferences with narrow terms to satisfy precision preferences since the amount of material retrieved in a system is not a simple function of the total numbers of terms posted to documents in the collection. At high cut-off values the retrieval power of broad and narrow terms tends to become equalized. Precision can be improved through raising the cut-off point and deleting broad terms. Experiments with weighted indexing provided poor results, and with title-term indexing gave inconclusive results. (AB)
Publication Type: N/A
Education Level: N/A
Sponsor: National Science Foundation, Washington, DC.
Authoring Institution: N/A
Identifiers: Precision Ratios
Note: A Dissertation Submitted to the Faculty of the Graduate Library School [Univ. of Chicago] in Candidacy for the Degree of Doctor of Philosophy