21.4 Hierarchical Ordering of Causal Tools

Causal inference tools can be categorized based on their methodological rigor, with randomized controlled trials (RCTs) considered the gold standard.

1. Experimental Design: Randomized Control Trials (Gold standard)

2. Quasi-experimental

   1. Regression Discontinuity

   2. Synthetic Difference-in-Differences

   3. Difference-In-Differences

   4. Synthetic Control

   5. Event Studies

   6. Fixed Effects Estimator

   7. Endogenous Treatment: mostly Instrumental Variables

   8. Matching Methods

   9. Interrupted Time Series

   10. Endogenous Sample Selection

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