A very well established phenomenon in the judgment and decision making tradition is the overconfidence one places in the amount of knowledge that one possesses. A recent important finding is that knowledge calibration varies not only individually but across cultures as well. Although the cross-cultural variation of the overconfidence phenomenon has been established, further research is needed to investigate if it replicates in other cultures. Furthermore, research efforts attempting to explain cross-cultural variations in the overconfidence phenomenon have seldom been made. Most of the research conducted has focused on establishing that there is variation in this phenomenon across cultures. Thus, the mechanisms behind this effect remain elusive. Two studies were conducted to investigate whether the overconfidence effect generalizes to Mexican-American and Mexican participants and whether culture-related variables such as preference for quick decision making, holistic reasoning, and uncertainty orientation predict calibration indices. Results of two studies conducted on White American (N = 179), Mexican-American (N = 264), and Mexican participants (N = 164) corroborate the cross-cultural variation of probability judgment accuracy. Holistic reasoning fully mediated the association between intuitive decision-making and overconfidence. As in previous studies, White American participants displayed less overconfidence when compared to Mexican-American and Mexican participants. Results of study 2 indicated that a rapid feeling of knowing is not predictive of memory performance on participants with a greater predisposition to reason holistically. More research needs to be conducted to: (1) investigate the specific mechanism by which holistic reasoning exerts its effect, and (2) explain discrepant findings observed between patterns of results for the two overconfidence indices computed.
