Unsupervised practice: The performance of the control group

A control group of 40 subjects practiced the Space Fortress game for 10, one-hour, sessions. They were given standard game instructions, but were not aided in their training in any other fashion. Subjects in this group showed a general improvement, throughout training, in the total game score as well as in many other aspects of game performance. However, individual differences were found in the subjects' initial capability, in their rate of learning and in the strategies they adopted to achieve their final performance. In order to summarize the many aspects of this complex database, two multivariate techniques were used: Three-Mode Principal Component Analysis and Cluster Analysis. These techniques proved useful in that they provided a coherent and relatively simple description of the subjects' behavior. The model derived from these multivariate procedures was applied to an independent group of subjects. This cross-validation accounted for some of the differences observed between the two groups.