The role of numeracy in judgment and decision making: the replication of eleven effects using several numeracy scales

Numeracy, representing the ability to understand and process information related to probabilities and numbers, is crucial for accurate decision making. This study evaluates the replicability of eleven effects that underscore the pivotal role of numeracy in judgment and decision making. Furthermore, the study explores the potential impact of employing diverse objective numeracy measures on the replicability of the tested effects. Additionally, we investigated correlations with various numeric competencies beyond objective numeracy, including subjective numeracy and approximate numeracy. We ran an online study on Polish-speaking Prolific users (N = 209). Six correlational effects were successfully replicated using the same numeracy measures as the original studies (decision rules, financial knowledge, consistency in risk perception, medical risk comprehension, maximizing the expected value, and preference for optimal options). Another two correlational effects were replicated using subjective instead of objective numeracy measures (resistance to sunk cost and financial well-being). Findings regarding the role of numeracy as a moderator variable were mixed. We found no evidence for the impact of numeracy on the strength of the framing effect. Nevertheless, more numerate individuals preferred the loss over the no-loss bet, and visual aids improved diagnostic inferences among participants with lower objective numeracy. This comprehensive examination provides valuable insights into the multifaceted interplay between numeracy and decision-making processes.