Interpretation of Conditional Probabilities in Probabilistic Interference Word Problems
Abstract
People's strategies on probabilistic inference word problems were investigated in an attempt to determine which of three theories explains their neglect of base rate information when estimating the probability of a hypothesis. These word problems present a base rate or prior probability (p(h)), some evidence (e) that typically conflicts with the prior expectation, and information on the reliability of the evidence, which is stated as p(e/h), the conditional probability of the evidence being seen if the hypothesis is true. The three theories are (a) subjects believe that the base rate is irrelevant; (b) they integrate base rate and evidence in a manner that underweighs the base rate; or (c) they misinterpret the reliability information p(e/h) as if it were p(h/e). Data using four distinct methods support the theory that subjects confuse the conditional probabilities. Keywords: Bayes theorem, Protocol analysis.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1990
- Accession Number
- ADA226907
Entities
People
- Michelle A. Miller
- Robert M. Hamm
Organizations
- University of Colorado Boulder