Conditional reasoning in context: a dual-source model of probabilistic inference.
A dual-source model of probabilistic conditional inference is proposed. According to the model, inferences are based on 2 sources of evidence: logical form and prior knowledge. Logical form is a decontextualized source of evidence, whereas prior knowledge is activated by the contents of the conditional rule. In Experiments 1 to 3, manipulations of perceived sufficiency and necessity mapped on the parameters quantifying prior knowledge. Emphasizing rule validity increased the weight given to form-based evidence relative to knowledge-based evidence (Experiment 1). Manipulating rule form (only-if vs. if-then) had a focused effect on the parameters quantifying form-based evidence (Experiment 3). The model also provides a parsimonious description of data from the so-called negations paradigm and adequately accounts for polarity bias in that paradigm (Experiment 4). Relationships to alternative conceptualizations of conditional inference are discussed.
Klauer
Karl Christoph
KC
Institut fur Psychologie, Albert-Ludwigs-Universität Freiburg, D-79085 Freiburg, Germany. klauer@psychologie.uni-freiburg.de
Beller
Sieghard
S
Hütter
Mandy
M
D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008128:Logic; D008297:Male; D008960:Models, Psychological; D015233:Models, Statistical; D011237:Predictive Value of Tests; D011336:Probability; D011340:Problem Solving; D055815:Young Adult