Projection Bias

What is projection bias?

Projection bias is a forecasting error in which people expect their future preferences to resemble their current preferences too closely. They may anticipate the direction of a change while underestimating its size.

Research foundation

Loewenstein, O’Donoghue, and Rabin’s 2003 paper reviews evidence and develops a formal model of the bias. The model concerns predicting future utility.

Projection bias example

A hungry person ordering food for later might recognize that hunger will decline but still overestimate how much food they will want. The relevant error is the difference between predicted and later preferences, not simply the decision to eat while hungry.

Projection bias versus false consensus

Projection bias, as defined here, concerns what you expect your future self to want. False consensus concerns overestimating how widely other people share your views or choices. A forecast about yourself and an estimate about other people are different judgments.

Projection bias in planning and consumption

A changed preference does not alone prove projection bias. The forecast, available information, and actual circumstances must be compared. The model can generate implications for planning and consumption.