We study the efficiency of oligopoly equilibria in congested markets. The motivating examples are the allocation of network flows in a communication network or of traffic in a transportation network. We show that increasing competition among oligopolists can reduce efficiency, measured as the...

This paper is a practical guide (a toolkit) for researchers, students and practitioners wishing to introduce randomization as part of a research design in the field. It first covers the rationale for the use of randomization, as a solution to selection bias and a partial solution to publication...

A longstanding question in the economics of the family is the relationship between sibship size and subsequent human capital formation and welfare. If there is a causal "quantity-quality trade-off," then policies that discourage large families should lead to increased human capital, higher...

This paper constructs a model of non-balanced economic growth. The main economic force is the combination of differences in factor proportions and capital deepening. Capital deepening tends to increase the relative output of the sector with a greater capital share, but simultaneously induces a...

We study the efficiency properties of oligopoly equilibria in congested networks. Our measure of efficiency is the difference between users' willingness to pay and delay costs. Previous work has demonstrated that in networks consisting of parallel links, efficiency losses from competition are...

This paper studies the optimal timing of unemployment insurance subsidies in a McCall search model. Risk-averse workers sequentially sample random job opportunities. Our model distinguishes unemployment subsidies from consumption during unemployment by allowing workers to save and borrow freely....

We study the optimal Mirrlees taxation problem in a dynamic economy with idiosyncratic (productivity or preference) shocks. In contrast to the standard approach, which implicitly assumes that the mechanism is operated by a benevolent planner with full commitment power, we assume that any...

The paper develops estimation and inference methods for econometric models with partial identification, focusing on models defined by moment inequalities and equalities. Main applications of this framework include analysis of game-theoretic models, regression with missing and mismeasured data,...

Under minimal assumptions finite sample confidence bands for quantile regression models can be constructed. These confidence bands are based on the "conditional pivotal property" of estimating equations that quantile regression methods aim to solve and will provide valid finite sample inference...

In the second half of the 1990s, the prospect of entry in the euro led to an output boom and large current account deficits in Portugal. Since then, the boom has turned into a slump. Current account deficits are still large, and so are budget deficits. This paper reviews the facts, the likely...