I Introduction

1 Questions about Questions

2 The Experimental Ideal

II The Core

3 Making Regression Make Sense

4 Instrumental Variables in Action: Sometimes You Get What You Need

5 Parallel Worlds: Fixed E¤ects, Di¤erences-in-di¤erences, and Panel Data

III Extensions

6 Getting a Little Jumpy: Regression Discontinuity Designs

7 Quantile Regression

8 Nonstandard Standard Error Issues

Last words

Acronyms

Empirical Studies Index

Notation