This study investigates how the grouping structure of information about others' outcomes in a risky environment with uncertain prospects affects individuals' beliefs about their own prospects. In particular, the study is focused on environments where an individual's risk is not meaningfully predicted by their group. Applying insights from prior literature on in-group/out-group biases in behavioral economics, the underlying hypothesis of this study is that individuals overweight information about in-group others relative to information about out-group others as a heuristic, even in the absence of a plausible reason to believe prospects are determined by group. As a result, with sufficiently small samples of information, individuals may have incorrect beliefs about their own prospects which lead them to take on a suboptimal amount of risk relative to their own preferences. Applications to health and environmental topics will be discussed.