Sociality of future outcomes moderates the effects of warmth and competence on social optimism bias.

People are overoptimistic about the future of those they like or admire (social optimism bias), expecting significantly more desirable than undesirable outcomes. By contrast, they are pessimistic about those they don't like. To operationalize the (dis)like of social targets, warmth and competence are used as two universal dimensions of social perception. In this pre-registered study, we replicate previous findings while adding two new levels of complexity. First, we make the distinction between the sociality of future outcomes: "alone" outcomes (e.g., enjoying a quiet afternoon by oneself) and "social" outcomes (e.g., enjoying a vacation with the significant other). Second, we investigate the effect of attachment styles on one's expectations for alone and social outcomes toward the social targets. In line with our hypotheses, the sociality of outcomes moderates both the additive and the multiplicative effects of the perceived warmth and competence of social targets on social optimism bias. Diverging from our hypotheses, we find that attachment anxiety and avoidance do not influence the effects of warmth and competence on social optimism bias. However, exploratory analyses reveal that attachment dimensions buffer the magnitude of social optimism bias for highly self-relevant social targets but do not impact social pessimism bias for irrelevant targets.