Explanations of the Use of Reliability Information as the Response in Probabilistic Inference Word Problems
Abstract
This document examines probabilistic word problems. Such problems (for example, the Blue/Green Cab Problem) require the subjects to state the probability of a hypothesis H, when they are given information about the base rate P(H), evidence E, and the reliability of the evidence thus the formula p(E/ H). A frequent wrong answer to the problem is to cite the reliability. Data from a study in which the subjects answered after receiving each piece of information are used to evaluate three explanations for the use of the reliability as the answer. Production system models state each hypothesis unambiguously. The hypothesis that subjects consider the base rate to be irrelevant in principle is rejected. The data are consistent with two hypotheses: that subjects confuse P(E/H) with p(H/E), and that they interpolate between the base rate probability and 1.0, but select their response from among nearby numbers which are available in the word problem. Keywords: Statistical inference; Information integration; Production systems; Heuristic strategies.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1988
- Accession Number
- ADA197060
Entities
People
- Robert M. Hamm
Organizations
- University of Colorado Boulder