This study examines decision-making behavior under risk using a repeated choices experimental design with immediate feedback. The aim is to investigate the heuristics of choice under risk and their performance when feedback is provided immediately after each decision. The experimental results reveal that participants demonstrate a notable inclination to take risks, which is consistent with prior research indicating an increase in risk-taking with experience. Furthermore, the overall performance of the 11 tested heuristics in predicting participant decisions is found to be relatively low, with the 'least likely' heuristic emerging as the top performer and the 'minimax' heuristic exhibiting poor performance across all measures and decision problem types.