Disentangling the multifaceted nature of certainty in evaluations

People hold their opinions and evaluations of objects with varying degrees of certainty. Understanding the nature of evaluation certainty is important, as it is a strong predictor of behavior. Several factors that impact certainty have been identified in past research, including value positivity, value extremity, and consistency in value-relevant evidence. However, whether these factors contribute uniquely to certainty or are statistically confounded remains unknown. The present work discusses four experiments (total N = 372) to disentangle these factors by leveraging the phenomenon of ensemble perception. We created pairs of ensembles (food baskets and retail good bundles) that are experimentally equalized on value positivity, value extremity, or evidence consistency, while systematically varying in evaluation certainty or evidence consistency. The results show independent contributions of value positivity and value extremity, but not evidence consistency, on ensemble evaluation certainty. Neither of the equalized factors fully accounts for evaluation certainty in the created ensembles, suggesting that it is a complex construct influenced by multiple independent factors. (PsycInfo Database Record (c) 2026 APA, all rights reserved).