Paradoxical decision-making and ecological rationality

Tom Waite
EEOB, The Ohio State University

(November 22, 2005 4:30 PM - 5:30 PM)

Paradoxical decision-making and ecological rationality

Abstract

Humans are notoriously susceptible to large biases in judgment, called cognitive illusions. Nonhuman animals are thought to be immune to such illusions because their decision-making has been shaped by natural selection. However, our research reveals that, like human consumers, gray jays show irrational preferences when choosing between options varying in quality and price. Standard models of choice assume decision makers evaluate options on relevant dimensions, assign fixed fitness-related values to options, and then make rational choices based on these values. If this were true, then an animal that prefers option a to b, and b to c, must prefer a to c. Likewise, the animal's preference for a over b should be unaffected by the introduction of a third, least preferable option. However, we have found clear violations of these and related predictions. I will give an overview of our experimental findings of economically irrational choice behavior. Throughout, I will describe our modeling attempts to uncover evolutionary explanations for this seemingly maladaptive behavior.