Economics Insights @ CBS

Companies in a variety of industries (e.g., airlines, hotels, theaters) often use last-minute sales to dispose of unsold capacity. Although this may generate incremental revenues in the short term, the long-term consequences of such a strategy are not immediately obvious: More discounted last-minute tickets may lead to more consumers anticipating the discount and delaying the purchase rather than buying at the regular (higher) prices, hence potentially reducing revenues for the company.

Valuations of entrepreneurial companies are only observed occasionally, albeit more frequently for well-performing companies. Consequently, estimators of risk and return must correct for sample selection to obtain consistent estimates. We develop a general model of dynamic sample selection and estimate it using data from venture capital investments in entrepreneurial companies. Our selection correction leads to markedly lower intercepts and higher estimates of risks compared to previous studies.

Teaching may be the most-scrutinized occupation in the economy. Over the past four decades, empirical researchers—many of them economists—have accumulated an impressive amount of evidence on teachers: the heterogeneity in teacher productivity, the rise in productivity associated with teaching credentials and on-the-job experience, rates of turnover, the costs of recruitment, the relationship between supply and quality, the effect of class size and the monetary value of academic achievement gains over a student's lifetime.

In November of 2007, the New York City Department of Education assigned each elementary and middle school a letter grade (A to F) as part of a new accountability system. Grades were based on continuous numeric scores derived from levels and changes in student achievement and other school environmental factors such as attendance, and were linked to a system of rewards and consequences for schools and principals. We use the discontinuities in the assignment of grades to estimate the impact of accountability in the short run.