Proof that previously used estimators of electoral incumbency advantage were biased, and a new unbiased estimator. Also, the first systematic demonstration that constituency service by legislators increases the incumbency advantage.
Proves that all previous measures of incumbency advantage in the congressional elections literature were biased or inconsistent, and develops an unbiased estimator based on a simple linear regression model. . 1990. Estimating Incumbency Advantage Without Bias, American Journal of Political Science 34: 1142–1164.Abstract
In this paper we prove theoretically and demonstrate empirically that all existing measures of incumbency advantage in the congressional elections literature are biased or inconsistent. We then provide an unbiased estimator based on a very simple linear regression model. We apply this new method to congressional elections since 1900, providing the first evidence of a positive incumbency advantage in the first half of the century.