SP500215 Appendix B: System Features Appendix National Institute of Standards and Technology D. K. Harman `IC. QUERY CONSThUCIION -- FEEDBACK (ADHOC) aries widely, about 20300. Mean not recorded but probably about 80. rm pool consisted of all terms from relevant documents and all terms entered by searcher in search statements. Terms were weighted using Robertson[OCRerr] archers' terms were given a bonus as if they had occurred in four out of five hypothetical relevant records. The top 20 terms were selected using the crit selection[OCRerr]value= term[OCRerr]weight * rels_containing[OCRerr]termIrels erm pool consisted of all terms from relevant documents. The top 10 terms as determined by w(p-q) were chosen for expansion and were searched togeth[OCRerr] [OCRerr]eiy terms. Terms were weighted using Robertson/Sparck-Jones F4.