Martha Pollack's work on this project has been supported by the Air Force Office of Scientific Research (F49620-96-1-0403) and an NSF Young Investigator's Award (IRI-9258392). David Joslin has been supported by Rome Labs (RL)ARPA (F30602-95-1-0023) and an NSF CISE Postdoctoral Research award (CDA-9625755). Massimo Paolucci has been supported by the Office of Naval Research, Cognitive and Neural Sciences Division (N00014-91-J-1694).
We are very grateful to Alfonso Gerevini for providing us with the code he used in his earlier study, and allowing us to use it in our experiments. We would also like to thank Arthur Nunes and Yazmine DeLeon, who assisted us in carrying out experiments done in the preliminary stages of this work. Finally, we thank Alfonso Gerevini, Len Schubert, Michael Wellman, and the anonymous reviewers for their helpful comments on this work.