TY  - RPRT
        AU  - Kolesár, Michal
AU  - Rothe, Christoph
        TI  - Inference in Regression Discontinuity Designs with a Discrete Running Variable
        PY  - 2016/Jun/
        PB  - Institute of Labor Economics (IZA)
        CY  - Bonn
        T2  - IZA Discussion Paper
        IS  - 9990
        UR  - https://www.iza.org/index.php/publications/dp9990
        AB  - We consider inference in regression discontinuity designs when the running variable only takes a moderate number of distinct values. In particular, we study the common practice of using confidence intervals (CIs) based on standard errors that are clustered by the running variable. We derive theoretical results and present simulation and empirical evidence showing that these CIs have poor coverage properties and therefore recommend that they not be used in practice. We also suggest alternative CIs with guaranteed coverage properties under easily interpretable restrictions on the conditional expectation function.
        KW  - discrete running variable
KW  - regression discontinuity design
KW  - clustered standard errors
        ER  -