SP500215 Appendix B: System Features Appendix National Institute of Standards and Technology D. K. Harman III. SEARCHING pends on number of terms, etc., etc. For the automatic adhoc run (cityan), the mean was 84 cpu seconds including ranking. rd to give a meaningftil number. The system was divided across 7 or 8 different SUN workstations of differing speeds. The total elapsed time for running the adhoc task) ranged from 12 to 24 hours, depending on distribution of machine load. Lr system uses n-gram matching of multiple query strings while scanning the original free text. It uses a weighting scheme on the different query strings based 0 Lhe original topic text. [OCRerr] than a second for a small query (3 terms) and 5 seconds for a query with 80 terms. 5 seconds total, 0.03 for local ranking, 0.02 for global ranking (among the cm5 processors). gligible -- heap used to extract top r accumulators, time is included above. pends on the number of terms etc., etc. For the automatic adhoc run with 5 come out tagged by query. Individual queries are already ranked, so hits our approach, retrieval time and ranking time cannot be separated. Experiment: topics 51-100 versus disk 3 First rank lOOOth rank # of #of avg. (median) avg. (median) docs feats [sec. CPU] (sec. CPU] 78'325 142 1.84 (1.12) 4.67 (4.58) 6'708 181 0.21 (0.15) 0£0 (0.80) 90'253 126 1.30 (1.27) 4.78 (4.60) 100'000 26 1.04 (0.97) 1.78 (1.67) 61'021 120 1.01 (0.88) 3.74 (3.75) 101-150 versus disks 1 and 2 #of #of docs feats APi 84'677 141 AP2 79'923 138 DOE1.1 100'000 42 DOB1.2 100'000 43 DOE1.3 26'087 43 FRi 26'207 166 FR2 20'108 170 wSJi 98'627 121 WSJ2 74'520 115 ZIFFi 75'180 107 ZIFF2 56'920 103 automatic query expansion (uclaa2), the mean was 84 wall-clock sec including emerge. AP3 PATN3 SJM3 ZIFF3.i ZIFF3.2 Fxperiment: topics First rank avg. (median) [sec. CPU] 1.47 (1.50) 1.38 (1.37) 1.42 (1.43) 1.41 (1.47) 0.41 (0.42) 0.68 (0.55) 0.57 (0.42) 1.64 (1.68) 1.17 (1.20) 1.27 (1.23) 0.90 (0.88) lOOOth rank avg. (median) [see. CPU] 5.18 (5.02) 4.96 (4.92) 2.93 (2.18) 2.98 (2.15) 0.92 (0.90) 2.22 (1.98) 1.77 (1.63) 5.96 (5.55) 3.57 (3.62) 4.22 (3.80) 2.90 (2.80)