Perceived patterns in decisions from experience and their influence on choice variability and policy diversification:...

Searching for and acting upon perceived patterns of regularity is a fundamental learning process critical for adapting to changes in the environment. Yet in more artificial, static settings, in which patterns do not exist, this mechanism could interfere with choice maximization and manifest as unexplained choice variability in later trials. Recently however, Ashby et al. (2017) found that choice variability in later trials of a repeated choice setting is correlated with levels of diversification in policy tasks, in which patterns can never be exploited. They concluded that in repeated choice tasks, choice-variability in later trials is unlikely the result of following perceived patterns. Here, we demonstrate that correlations between choice variability and policy diversification can actually be the result of pattern seeking, rather than serving as evidence against it. We review evidence for the robustness of pattern seeking mechanisms in repeated choices and explain how such mechanisms could in fact create the results observed by Ashby et al. To examine our interpretation for their results, we conducted a sequential dependencies analysis of their data and find evidence that many participants behaved as if they believed trials are inter-dependent, even though they were explicitly instructed that the environment is stationary. The results of a new experiment in which sequential patterns are directly manipulated support our interpretation: Experiencing patterns affected both choice variability in later trials and policy diversification. Finally, we argue that decisions from experience tasks are a valid tool to examine the generation of preferences via fundamental learning processes.