I would like to present two links to papers that I will bring up in my presentation. They clarify the finer points about learning and the latest performance of the ARACHNID algorithm:
   http://citeseer.nj.nec.com/menczer99adaptive.html
   http://dollar.biz.uiowa.edu/~fil/Papers/sigir-01.pdf

Greg, match(k,Q) makes a binary determination deciding if the words of the query occur in the document. Think of it as "for each word of the document, is it a query term?"

Thanks for the comments, everyone. See you tomorrow!