SP500207 Appendix C: System Features appendix National Institute of Standards and Technology Donna K. Harman II. Query construction (please till out a section for e[OCRerr]tch query construction method used) A large numl)er of techniques were tried. A. Automatically built queries (ad hoc) 1. topic fields used Boolean queries were constructed from a variety of the topic tields. The (lueries were then ranked p()ssil)Iy using ditTerent flelds. 2. total computer time to build query (cpu seconds) -10 3. which of the followiug were used? a. term weightilig wi[OCRerr] weights b£Lsed on tenns in topics b. phrase extraction from topics i. automatic addition of B(x)lean connectors or proximity operators III. Searching A. Total computer tilne to search (cpu seconds) 1. retrieval tilne (total cpu seconds between when a query enters die system until a list of document numbers are obtained) 2. ranking time (total cpu seconds to sort d(icument list) These operations (wcurred together. It t()()k 6 lirs to ol)tain a ranked list of 1,000 documents for each of the 50 queries. B. Which methods best describe your machine searching mediods? 1. vector space m(XIel C. What factors are included in your ranking? 1. tenn frequency 2. inverse d(icument frequency 7. proxilnity of terms 9. docuinent lengtli 15. other (specify) The location of the term in the query. A variety of modeLs were tried. IV. What machine did [OCRerr]()[OCRerr] conduct die TREC experiment (m? Sun SPARC 2 How much RAM did it have? 128 Ml) What w[OCRerr]is the clock rate of tile CPU? 25 MIP V. Some systems are research prototypes and others are commercial. To help compare diese systems: I. How much "software CIIL'iilCCflIit(Y" went into the development of your system? The system is a rol)ust research tool. Limited eff([OCRerr]rt has heen put into speed. 2. Given appropriate resources, could your system be made to run faster? By how much (estimate)? Consideral)Iy faster, hut we estimate it would twice [OCRerr]s f[OCRerr][OCRerr]t if we changed the architecture (we use UNIX pipCs to communicate). It Ls unclear what other speed-ups can ([OCRerr]cur. 3. What features is your system missing that it would benefit by if it had them? All sorts of things would l)e nice! A go([OCRerr] form of transaction management would lie the most useful t(J transform the system into a commercial product. 491