Artificial Intelligence Laboratory MIS Department, University of Arizona, 1130 E. Helen St, Tucson, AZ 85721, USA. dmm@eller.arizona.edu <dmm@eller.arizona.edu>|Artificial Intelligence Laboratory MIS Department, University of Arizona, 1130 E. Helen St, Tucson, AZ 85721, USA. dmm@eller.arizona.edu <dmm@eller.arizona.edu>|Artificial Intelligence Laboratory MIS Department, University of Arizona, 1130 E. Helen St, Tucson, AZ 85721, USA. dmm@eller.arizona.edu <dmm@eller.arizona.edu>|Artificial Intelligence Laboratory MIS Department, University of Arizona, 1130 E. Helen St, Tucson, AZ 85721, USA. dmm@eller.arizona.edu <dmm@eller.arizona.edu>