This paper reports some experiments on probabilistic reasoning designed to investigate the impact of the probabilistic problem presentation format (verbal-numerical and graphical-pictorial) on subjects' confidence in the correctness of their performance, other than the calibration between confidence and accuracy. To understand the potential effect…

The second response conditional probability model of decision-making strategies used by examinees answering multiple choice test items was revised. Increasing the number of distractors or providing distractors giving examinees (N=106) the option to follow the model improved results and gave a good fit to data for 29 of 30 items. (SLD)