13.6 Validating assumptions
- Continuity and local randomization assumptions inherently untestable but “empirical implications” testable (Skovron and Titiunik 2015, 26)
- General problem: Researcher has no control over assignment
- If cut-off known to units → danger of score change/manipulate
- Q: Can you think of an example of score manipulation?
- Qualitative tests of assumptions
- Explore how manipulable score/assignment are
- e.g., institutional appeal possibility (changing of scores)
- e.g.a Administrative process of score assignment
- Explore how manipulable score/assignment are
- Quantitative tests of assumptions
- Density of the running variable around the cutoff: Local N below/above cutoff very different? (Q: Why?)
- Treatment effect on pre-treatment covariates or placebo outcomes: Are treated units near the cutoff similar to control units? (Q: Why?)
- Treatment effect at alternative fake/placebo cutoff values (Q: Why?)
- The three quant. tests differ between continuity- and randomization-based approach
References
Skovron, Christopher, and Rocıo Titiunik. 2015. “A Practical Guide to Regression Discontinuity Designs in Political Science.”