ARTICLE
ABSTRACT
A caliper mechanism is a common tool used to prevent from inexact matches. The existing literature discusses asymptotic properties of matching with caliper. In this simulation study we investigate properties in small and medium sized samples. We show that caliper causes a significant bias of the ATT estimator and raises its variance in comparison to one-to-one matching.
KEYWORDS
propensity score matching, caliper, Monte Carlo experiment, finite sample properties
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