Publicly funded exam schools educate many of the world's most talented students. These schools typically contain higher achieving peers, more rigorous instruction, and additional resources compared to regular public schools. This paper uses a sharp discontinuity in the admissions process at...

I analyze changes in teacher turnover, hiring, effectiveness, and salaries at traditional public schools after the opening of a nearby charter school. While I find small effects on turnover overall, difficult to staff schools (low-income, high-minority share) hired fewer new teachers and...

Unlike in elementary school, high-school teacher effects may be confounded with both selection to tracks and unobserved track-level treatments. I document sizable confounding track effects, and show that traditional tests for the existence of teacher effects are likely biased. After accounting...

This chapter provides a selective review of some contemporary approaches to program evaluation. One motivation for our review is the recent emergence and increasing use of a particular kind of "program" in applied microeconomic research, the so-called Regression Discontinuity (RD) Design of...

Using a wide array of examples from the literature and from original estimates, this essay examines the pitfalls that make good empirical research in labor economics as much art as science. Appropriateness and cleanliness of data are considered, as are problems of extreme observations and...

It has long been recognized in finance and other literature that variance provides option value. The same point carries over to the labor market. Firms like variance in new employees because they can keep the good workers and terminate the bad ones. But market wages must adjust to make the...

Illegal arms are responsible for thousands of deaths in civil wars every year. Yet, their trade is very hard to detect. We propose a method to statistically detect illegal arms trade based on the investor knowledge embedded in financial markets. We focus on eight countries under UN arms embargo...

A wide range of social indicators turned sharply negative for Blacks in the late 1980s and began to rebound roughly a decade later. We explore whether the rise and fall of crack cocaine can explain these patterns. Absent a direct measure of crack cocaine%u2019s prevalence, we construct an index...

The twentieth century was a time of rapid globalization for advanced art. Artists from a larger number of countries made important contributions than in earlier periods, and they did so in a larger number of places. Many important innovations also diffused more rapidly, and more widely, than in...

Many have observed that individuals perform worse after having received a promotion. The most famous statement of the idea is the Peter Principle, which states that people are promoted to their level of incompetence. There are a number of possible explanations. Two are explored. The most...