Streakiness is not a theory: On “momentums” (hot hands) and their underlying mechanisms

The term momentum (or hot hand) is widely used by researchers from various disciplines when addressing streakiness. Indeed, stock prices, presidential approval ratings, students’ grades, and basketball games outcomes might all exhibit some degree of serial correlation. Over time, serial correlation assessment has evolved into a thriving research field, and it might have become a rather technical and specific matter if not for the concept of momentum that provides this “conquest for streakiness” with some theoretical underpinning and a general appeal. In this paper, we distinguish between within-contest, across-contest, and other types of serial dependencies. We also elaborate on the psychophysiological mechanisms underlying the within-contest success breeds success effect. We then bridge between literature on goal setting, high performance cycle, and momentum, as a means for addressing across-contest dependency in performance. Finally, we emphasize that the underlying mechanisms of the within-contest and across-contest success breeds success effect cannot readily explain serial correlation in other spheres. We therefore encourage researchers to go beyond simply labeling their researched phenomenon as momentum (or hot hand), instead developing more specific models and descriptions of the underlying mechanisms.