CRANV2
Aslib Cranfield Research Project: Factors Determining the Performance of Indexing Systems: Volume 2
Simulated ranking and document output cut-off
chapter
Cyril Cleverdon
Michael Keen
Cranfield
An investigation supported by a grant to Aslib by the National Science Foundation.
Use, reproduction, or publication, in whole or in part, is permitted for any purpose of the United States Government.
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% PRECISION
FIGURE 5.5P MAXIMUM POSSIBLE
PERFORMANCE CURVE WITH
DOCUMENT OUTPUT CUT-OFF
FOR CRANFIELD TEST
COLLECTION OF ,200
DOCUMENTS AND 42
QUESTIONS.
FIGURE 5,6P POLAR GRAPH OF RESULTS
FOR INDEX LANGUAGE 1.1 .a
{FIG. 4.140T) AND INDEX
LANGUAGE 1.6,a(FIG. 4.203T)
(COORDINATION LEVEL
CUTOFFS)
o I.i,a x 1.6.a