Cognitive Science & Policy Hub // Vol. 12

Behavioral Economics Lab

The Nudge & Bias Lab — an interactive, citable directory of cognitive biases, peer-reviewed journals, and empirical nudge findings.

Risk & Loss

Prospect Theory: An Analysis of Decision under Risk

Daniel Kahneman, Amos Tversky

Econometrica · 1979

Abstract

The bedrock paper of behavioral economics, presenting an alternative to expected utility theory. It shows that human beings make decisions based on the potential value of losses and gains rather than the final outcome, evaluating these choices relative to a subjective reference point.

Methodology

Subjecting participants to hypothetical choice problems involving varying levels of risk, probability, and payouts. Responses were systematically analyzed to expose departures from rational choice theory.

Findings

Discovered three key principles: (1) Reference Dependence (outcomes are compared to a baseline); (2) Loss Aversion (losses loom larger than gains); and (3) Non-linear Probability Weighting (people over-weight small probabilities and under-weight large ones).

Applied nudge

Reframe standard value propositions by highlighting what is lost rather than what is gained, and position user progress relative to a custom reference point.

Citation

Kahneman, D., & Tversky, A. (1979). Prospect theory: An analysis of decision under risk. Econometrica, 47(2), 263-291.