The three main techniques in today's econometric toolbox are differences-in-differences techniques, which take advantage of policy changes, instrumental variables techniques for analyzing natural experiments, and linear regression for statistical control. These methods answer direct causative issues in the context of the contemporary experimentalist paradigm, such as: Do smaller classes improve learning? Are spouse abusers deserving of an arrest? To what extent does schooling increase pay? A Most Harmless Econometrics demonstrates how the fundamental instruments of applied econometrics let the data tell the story. Mostly Harmless Econometrics contains significant new developments, such as quantile regression and regression-discontinuity designs, in addition to the fundamentals of econometrics. It also explains how to calculate standard errors accurately.J?rn-Steffen Pischke and Joshua Angrist demonstrate why more sophisticated econometric procedures are usually superfluous or even hazardous. This book emphasizes practical econometric methods that are applicable to a wide range of modern social science fields and are simple to use. A mocking overview of the fundamentals of econometrics an emphasis on the most popular tools used by applied researchers sections on quantile regression, standard errors, and regression-discontinuity designs Numerous real-world scenarios A resource that is both clear and straightforward and has many uses