Contents
What is the key identification assumption for RDD?
A fundamental assumption of the RDD is that there is a discontinuous change in the probability of exposure at the assignment cut-off. Therefore, we first assessed whether discontinuity of exposure was present in our study.
How is the treatment assigned in an RDD?
In the RDD, researchers assign students to treatment or control groups on the basis of a single assignment variable – often a test score, but potentially any continuous variable – and a specified cutoff value. Students with scores of 50 or above (the cutoff) receive aid, and those with scores below 50 do not.
What is the identification assumption for regression discontinuity design?
Required assumptions. Regression discontinuity design requires that all potentially relevant variables besides the treatment variable and outcome variable be continuous at the point where the treatment and outcome discontinuities occur.
How is RDD easily conveyed in a picture?
RDD is intuitive and easily conveyed by a picture showing sharp changes in » treatment assignment, and » average outcomes around cut-off value of assignment variable 3. There are several different ways to estimate the treatment effect, each of which have credible causal interpretations
Is the assignment to treatment and control RDD?
RDD Intuition RDD is a quasi-experimental technique » Assignment to treatment and control is notrandom – Treatment and Control groups may differ systematically in ways related to the outcome…not good because then outcome may not be due to treatment
How is regression discontinuity design used in RCT?
Regression discontinuity design (RDD) is a popular quasi-experimental design used to evaluate program effects. It differs from the randomized control trial (RCT) mainly in the assignment of study subjects. In RCT, subjects are assigned to the treatment group(s) and control group randomly.
Is the RD Design used in other disciplines?
Treatment is, thus, the RD design in economics is unique as it is still rarely used in other disciplines. 2 See, however, two recent overview papers by van der Klaauw (2008b) and Guido W. Imbens and Thomas Lemieux (2008) that have begun bridging this gap.