This is a survey of the economic principles that underlie antitrust law and how those principles relate to competition policy. We address four core subject areas: market power, collusion, mergers between competitors, and monopolization. In each area, we select the most relevant portions of...

We present and test an explanation for lags in the adjustment of wholesale gasoline prices to changes in crude oil prices. Our simple model with costly adjustment of production and inventories implies that output prices will respond with a lag to cost shocks even in the absence of menu costs,...

This paper compares alternative liability rules for allocating losses from defective products when consumers under- estimate these losses and producers may have some market power. If producers do not have any market power, the rule of strict liability .leads to both the first-best accident...

The recent fall of labor's share of GDP in numerous countries is well-documented, but its causes are poorly understood. We sketch a “superstar firm” model where industries are increasingly characterized by “winner take most” competition, leading a small number of highly profitable (and...

This paper estimates the extent to which market power is a source of production misallocation. Productive inefficiency occurs through more production being allocated to higher-cost units of production, and less production to lower-cost production units, conditional on a fixed aggregate quantity....

We document the evolution of markups based on firm-level data for the US economy since 1950. Initially, markups are stable, even slightly decreasing. In 1980, average markups start to rise from 18% above marginal cost to 67% now. There is no strong pattern across industries, though markups tend...

The fall of labor's share of GDP in the United States and many other countries in recent decades is well documented but its causes remain uncertain. Existing empirical assessments of trends in labor's share typically have relied on industry or macro data, obscuring heterogeneity among firms. In...