Typical versus atypical unpacking and superadditive probability judgment.

Probability judgments for packed descriptions of events (e.g., the probability that a businessman does business with a European country) are compared with judgments for unpacked descriptions of the same events (e.g., the probability that a businessman does business with England, France, or some other European country). The prediction that unpacking can decrease probability judgments, derived from the hypothesis that category descriptions are interpreted narrowly in terms of typical instances, is contrasted to the prediction of support theory that unpacking will generally increase judged probabilities (A. Tversky & D. J. Koehler, 1994). The authors varied the typicality of unpacked instances and found no effect of unpacking with typical instances (additivity) and a negative effect with atypical instances (superadditivity). Support theory cannot account for these findings in its current formulation.

[1]  Padraic Monaghan,et al.  Proceedings of the 23rd annual conference of the cognitive science society , 2001 .

[2]  A. Tversky,et al.  Options traders exhibit subadditive decision weights , 1996 .

[3]  S. Sloman,et al.  Similarity and symbols in human thinking , 1998 .

[4]  Derek J. Koehler,et al.  The enhancement effect in probability judgment , 1997 .

[5]  C. Fox Strength of Evidence, Judged Probability, and Choice Under Uncertainty , 1999, Cognitive Psychology.

[6]  Derek J. Koehler,et al.  Subjective Probability of Disjunctive Hypotheses: Local-Weight Models for Decomposition of Evidential Support , 1999, Cognitive Psychology.

[7]  Eric J. Johnson,et al.  Framing, probability distortions, and insurance decisions , 1993 .

[8]  A. Tversky,et al.  Extensional versus intuitive reasoning: the conjunction fallacy in probability judgment , 1983 .

[9]  S. Sloman,et al.  Judging the Probability of Representative and Unrepresentative Unpackings , 2001 .

[10]  E. Rosch,et al.  Family resemblances: Studies in the internal structure of categories , 1975, Cognitive Psychology.

[11]  A. Tversky,et al.  Heuristics and Biases: Unpacking, Repacking, and Anchoring: Advances in Support Theory , 2002 .

[12]  Lyle Brenner,et al.  Focus, repacking, and the judgment of grouped hypotheses , 1999 .

[13]  A. Tversky,et al.  A Belief-Based Account of Decision Under Uncertainty , 1998 .

[14]  Daniel Kahneman,et al.  Availability: A heuristic for judging frequency and probability , 1973 .

[15]  S. Sloman Part-set cuing inhibition in category-instance and reason generation , 1991 .

[16]  L. Barsalou Ideals, central tendency, and frequency of instantiation as determinants of graded structure in categories. , 1985, Journal of experimental psychology. Learning, memory, and cognition.

[17]  G. Murphy,et al.  The Big Book of Concepts , 2002 .

[18]  Derek J. Koehler,et al.  An evidential support accumulation model of subjective probability , 2003, Cognitive Psychology.

[19]  A. Tversky,et al.  Support theory: A nonextensional representation of subjective probability. , 1994 .

[20]  J. Hampton Similarity-based categorization and fuzziness of natural categories , 1998, Cognition.

[21]  Kelly E. See,et al.  Belief and Preference in Decision Under Uncertainty , 2006 .

[22]  D. Krantz,et al.  A Note on Superadditive Probability Judgment , 1999 .

[23]  C. Fox,et al.  Forecasting Trial Outcomes: Lawyers Assign Higher Probability to Possibilities That Are Described in Greater Detail , 2002, Law and human behavior.

[24]  D A Redelmeier,et al.  Probability judgement in medicine: discounting unspecified possibilities. , 1995, Medical decision making : an international journal of the Society for Medical Decision Making.

[25]  N. Sanders,et al.  Journal of behavioral decision making: "The need for contextual and technical knowledge in judgmental forecasting", 5 (1992) 39-52 , 1992 .

[26]  L. Macchi,et al.  Thinking : psychological perspectives on reasoning, judgment and decision making , 2005 .

[27]  R S Nickerson,et al.  Retrieval inhibition from part-set cuing: A persisting enigma in memory research , 1984, Memory & cognition.

[28]  N. J. Slamecka,et al.  An examination of trace storage in free recall. , 1968, Journal of experimental psychology.

[29]  L. Brenner,et al.  Similarity between Hypotheses and Evidence , 1999, Cognitive Psychology.