ISR11 A Modified Two-Level Search Algorithm Using Request Clustering chapter V. R. Lesser Harvard University Gerard Salton Use, reproduction, or publication, in whole or in part, is permitted for any purpose of the United States Government. vii-~6 Case 17 - The Modified T'TO-Level Search Scheme with 10 Categories Based on the Clustering of 200 Random [OCRerr]ueries with the Full 35 Queries Used as a Test Collection of [OCRerr]ueries n c K(c,n) M(c,n) [OCRerr](c,n) R(c,n) 3 .20 35 3.46 .43 6 .20 33 7.42 .61 9 .20 29 13.38 .66 .60 12 .20 28 21.68 .74 .71 .30 33 9.00 .70 .48 6 .30 23 16.48 .8i .57 9 .30 12 19.00 .84 .83 12 .30 9 21.44 .87 .78 5.14 .81 .71 6 7 18.71 .93 .57 9 1 9.00 .89 1.00 12 1 12.00 .83 1.00 3 .50 3 3.00 .78 1.00 6 .50 1 7.00 .83 1.33 9 50 0 0 0 0 12 .50 0 0 0 0 .60 1 3.00 .67 2.00 6 .60 0 0 0 `0 9 .60 0 0 0 0 12 .60 0 0 0 0 TOTALS 230 = 11.74 P = .70 T R = .60 T