# The Perils of Peer Effects

@article{Angrist2013ThePO, title={The Perils of Peer Effects}, author={Joshua David Angrist}, journal={ERN: Other Econometrics: Econometric Model Construction}, year={2013} }

Individual outcomes are highly correlated with group average outcomes, a fact often interpreted as a causal peer effect. Without covariates, however, outcome-on-outcome peer effects are vacuous, either unity or, if the average is defined as a leave-out mean, determined by a generic intraclass correlation coefficient. When pre-determined peer characteristics are introduced as covariates in a model linking individual outcomes with group averages, the question of whether peer effects or social… Expand

#### 430 Citations

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