Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2004.Includes bibliographical references (p. 149-151).Structure distinguishes music from noise. When formulating that structure, musical artists rely on both mental representations and sensory perceptions to organize pitch, rhythm, harmony, timbre and dynamics into musical patterns. The generative process may be compared to playing a game, with goals, constraints, rules and strategies. In this study, games serve as a model for the interrelated mechanisms of music creation, and provide a format for an experimental technique that constrains creators as they generate simple rhythmic patterns. Correlations between subjects' responses and across experiments with varied constraints provide insight into how structure is defined in situ and how constraints impact creators' perceptions and decisions. Through the music composition games we investigate the nature of generative strategizing, refine a method for observing the generative process, and model the interconnecting components of a generative decision. The patterns produced in these games and the findings derived from observing how the games are played elucidate the roles of metric inference, preference and the perception of similarity in the generative process, and lead us to a representation of generative decision tied to a creator's perception of structure.M. Nyssim Lefford.Ph.D