Mathematical Psychology
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Elimination by Aspects

Tversky's Elimination by Aspects model describes multi-alternative choice as a sequential process of selecting important attributes and eliminating alternatives that lack the required level on each attribute.

Elimination by Aspects (EBA), proposed by Amos Tversky in 1972, provides an alternative to Luce's Choice Axiom for multi-alternative choice. Rather than evaluating all options simultaneously, EBA describes choice as a sequential elimination process: the decision maker selects an important attribute (aspect), sets a criterion, and eliminates all alternatives that fail to meet it. This continues until one alternative remains.

The EBA Process

Elimination by Aspects 1. Select aspect α with probability proportional to its weight w(α)
2. Eliminate all alternatives that lack aspect α
3. If one alternative remains: choose it
4. Otherwise: return to step 1 with remaining alternatives

Violations of IIA

EBA naturally produces violations of the Independence from Irrelevant Alternatives (IIA) property: adding a new option that is similar to an existing option "steals" more eliminations from the similar option than from dissimilar ones. This correctly predicts the similarity effect (adding a similar option reduces the share of the original more than of dissimilar alternatives) — a violation that Luce's Choice Axiom cannot accommodate.

EBA provides a psychologically plausible account of how people simplify complex multi-attribute decisions through sequential attention to individual attributes. It has influenced models of consumer choice, voting behavior, and satisficing strategies in bounded rationality.

Related Topics

References

  1. Tversky, A. (1972). Elimination by aspects: A theory of choice. Psychological Review, 79(4), 281–299. https://doi.org/10.1037/h0032955
  2. Tversky, A. (1972). Choice by elimination. Journal of Mathematical Psychology, 9(4), 341–367. https://doi.org/10.1016/0022-2496(72)90011-9
  3. Gigerenzer, G., & Goldstein, D. G. (1996). Reasoning the fast and frugal way: Models of bounded rationality. Psychological Review, 103(4), 650–669. https://doi.org/10.1037/0033-295X.103.4.650
  4. Payne, J. W., Bettman, J. R., & Johnson, E. J. (1993). The Adaptive Decision Maker. Cambridge University Press. https://doi.org/10.1017/CBO9781139174237

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