Acknowledgements

Thanks to Stephen Robertson and Stephen Walker for making
OKAPI available to UCLA.

  We are especially thankful to Stephen Walker for all his con-
tinuing help over and above that indicated in the text.

  We wish to thank Donna Harman of NIST for her support
during TREC-2.

  This research was supported by a UCLA Academic Senate
grant that also provided financial support for the graduate re-
search assistantship of PVB.

  Finally, ENE is grateful to SUN Microsystems Inc. for the
equipment grant of the SPARC 2 that made this research p05-
sible.

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A    Runs

The runs presented here are grouped by algorithm used for the
expansion. The list starts with runs that did not include query
expansion.

  bmlS.phn.qen.uclagsln
bmlS.phn.qen.uclagsly
bmlS.phy.qen.uclagsly
bmlS.phb.qen.uclagsly

bmlS.phb.qey:wpq-10-5.uclagsln
bmlS.phb.qey:wpq-10-5.uclagsly
bmlS.phb.qey:wpq-10-10.uclagsln
bmlS.phb.qey:wpq-10-10.uclagsly
bmlS.phb.qey:wpq-10-15.uclagsln
bmlS.phb.qey:wpq-20-5.uclagsln
bmlS.phb.qey:wpq-20-10.uclagsln
bmls.phb.qey:wpq-20-15.uclagsln
bmlS.phb.qey:wpq-30-5.uclagsln
bmlS.phb.qey:wpq-30-10.uclagsln
bmlS.phb.qey:wpq-30-15.uclagsln

bmlS.phb.qey:emim-10-10.uclagsln
bmlS.phb.qey:emim-10-10.uclagsly
bmlS.phb.qey:emim-20-10.uclagsly
bmlS.phb.qey:emim-30-10.uclagsly

bmlS.phb.qey:port-10-10.uclagsln
bmlS.phb.qey:port-10-10.uclagsly
bmlS.phb.qey:port-20-10.uclagsly
bmlS.phb.qey:port-30-10.uclagsly

bm15.phb.qey:r~hi1o-10-10.uclagsln
bm15.phb.qey:r~hilo-10-10.uclagsly

bmlS.phb.qey r lohi 10 5.uclagsln
bmlS.phb.qey r lohi 10 10.uclagsln
bmlS.phb.qey r lohi 10 10.uclagsly
bmlS.phb.qey r lohi 10 15.uclagsln
bmlS.phb.qey r lohi 20 5.uclagslu
bmlS.phb.qey r lohi 20 l0.uclagsln
bmlS.phb.qey.rAohi 20 15.uclagsln
bmlS.phb.qey:rAohi-30-5.uclagsln
bmlS.phb.qey:rAohi-30-10.uclagsln
bm15.phb.qey:r~lohi-30-15.uclagsln