How environmental regularities affect people's information search in probability judgments from experience

Area of Science:

• Cognitive Psychology
• Decision Science
• Behavioral Economics

Background:

• Everyday experience often involves smaller rewards occurring with higher probability than larger rewards.
• This ecological reward-probability correlation may shape expectations in experimental settings.
• Understanding these prior beliefs is crucial for decision-making research.

Purpose of the Study:

• To investigate if people's probability judgments are influenced by the correlation between reward size and probability.
• To examine how the representativeness of an environment affects information search and integration in probability judgment tasks.
• To determine if prior beliefs about reward-probability regularities impact reliance on small sample sizes.

Main Methods:

• Study 1: Assessed probability judgments under uncertainty, examining expectations of reward-probability correlations.
• Study 2: Employed an experience-based probability judgment task with manipulated reward-probability correlations (negative, positive, none).
• Analyzed participants' search effort and integration of sample-based uncertainty.

Main Results:

• Participants in Study 1 assumed larger rewards were less likely, mirroring real-world patterns.
• In Study 2, participants sampled fewer outcomes when the reward-probability relationship was ecologically representative (negatively correlated).
• Despite varied conditions, participants consistently treated observed outcomes as representative, failing to integrate sample-based uncertainty.

Conclusions:

• Prior beliefs about environmental regularities, like the reward-probability correlation, influence behavior in experimental settings.
• People may default to using small sample sizes due to ingrained assumptions about outcome distributions.
• These findings offer insights into judgment and decision-making from experience, highlighting the role of ecological validity.