ARGUMENTS IN THE PRACTICAL REASONING UNDERLYING CONSTRUCTED PROBABILITY RESPONSES

Reasoning is an important cognitive activity in probability assessment , and one that has been understudied. This proposition motivates the p aper's three general aims. First, based on research in rhetoric, we pr esent a theoretical means of analyzing the arguments constructed durin g the reasoning that occurs in probability assessment. Second, from ve rbal protocol data, we establish that subjects constructed arguments i n forming beliefs and assessing the associated probabilities. Third, w e analyze the data for the structure of subjects' arguments, including argument content and form. Subjects used a limited amount of relevant evidence and used a variety of argument forms that could be character ized by the nature of the knowledge that subjects brought to bear in f orming the arguments. Subjects predominantly used causal reasoning, bu t also employed hierarchical category knowledge, resemblance relations hips, and arguments from authority. These findings form a basis for ex panding our accounts of probability assessment and for improving asses sment practice.