Knowledge that Transforms

We identify cyclical turning points for 74 U.S. manufacturing industries and uncover new empirical regularities: (a) industries tend to comove between expansion and contraction phases over the business cycle; (b) clusters of industry turning points are highly asymmetric between peaks and troughs: troughs are much more concentrated and sharper than peaks; (c) the temporal pattern of phase shifts across industries supports the spillovers through input-output linkages; and (d) macroeconomic shocks, such as unanticipated changes in monetary policy, government spending, oil prices, and financial conditions, are significant drivers of industrial phase shifts.

This paper proposes a novel matching estimator where neighbors used and weights are endogenously determined by optimizing a covariate balancing criterion. The estimator is based on finding, for each unit that needs to be matched, sets of observations such that a convex combination of them has the same covariate values as the unit needing matching or with minimized distance between them. We implement the proposed estimator with data from the National Supported Work Demonstration, finding outstanding performance in terms of covariate balance. Monte Carlo evidence shows that our estimator performs well in designs previously used in the literature.

Does online availability boost citations? Using a panel of citations to economics and business journals, we show that the enormous effects found in previous studies were an artifact of their failure to control for article quality, disappearing once fixed effects are added as controls. The absence of aggregate effects masks heterogeneity across platforms: JSTOR has a uniquely large effect, boosting citations around 10%. We examine other sources of heterogeneity, including whether JSTOR disproportionately increases cites from developing countries or to “long-tail” articles. Our theoretical analysis informs the econometric specification and allows citation increases to be translated into welfare terms.

Originators seek to mitigate the loss of monopoly power by authorizing generic entry prior to patent expiry. Off-patent competition may be adversely affected if authorized generic entry substantially lowers the attractiveness of subsequent generic entry. This study assesses the impact of authorized generic entry on independent generic entry in recent cases of patent expiry in Germany. The results of a recursive bivariate probit regression, accounting for the endogeneity of authorized generic entry, show that authorized generic entry has no significant effect on the likelihood of generic entry. Business scope expansion and rent-seeking motives drive authorized generic entry decisions.

We argue that the rise of online travel agencies changed the nature of competition in the airline industry—from competition on elapsed scheduled flight times to price competition. Using flight-level data between 1997 and 2007 and geographical Internet growth patterns, we find a positive relationship between Internet access and flight times. The magnitude of this relationship is larger in competitive markets without low-cost carriers and for flights with shortest scheduled times. We also find that flight delays increased as more passengers gained Internet access. These findings suggest that the Internet may adversely affect firms’ performance and incentives to provide high-quality products.

This paper capitalizes on a unique situation in Israel where car insurance coverage is often distributed as a benefit by employers. In our sample, employer-determined coverage resulted in an average $235 discount in accident costs. Using instrumental variable analysis on data provided by an insurance firm in Israel (2001–2008), we find that each $100 reduction in accident costs results in a 1.7 percentage point increase in the probability of an accident. At an average accident rate of 16.3 percent, this 10 percent increase in auto accidents can be interpreted as the effect of moral hazard on car accidents.

We propose a methodology for estimating the competition effects from entry when firms sell differentiated products. We first derive precise conditions under which Bresnahan and Reiss’s entry threshold ratios (ETRs) can be used to measure competition effects. We then augment the traditional entry model with a revenue equation. This serves to adjust the ETRs by the extent of market expansion from entry, giving unbiased estimates of the competition effects. We apply our approach to seven local service sectors. We find that entry typically leads to significant market expansion, implying that traditional ETRs may substantially underestimate the competition effects from entry.

Do banks matter for growth, and if so, how? This paper examines the effects of national banks in the United States from 1870 to 1900. I use the discontinuity in entry caused by a large minimum size requirement to identify the effects of banking. For the counties on the margin between getting a bank and not, gaining a bank increased production per person by 10%. National banks in rural areas improved agriculture over manufacturing, moving counties toward geographic comparative advantage. Since these banks made few long-term loans, the evidence suggests that the provision of working capital and liquidity matters for growth.

This paper presents a new empirical regularity between the volatility of productivity growth and long-run unemployment for a given level of long-run productivity growth. A theoretical framework based on asymmetric real wage rigidities is shown to have the potential to rationalize this finding. The model tends to fit U.S. long-run unemployment better than a specification based on long-run productivity growth only, especially during the Great Moderation and the Great Recession.