The extensive empirical macro- and micro-level evidence on the impact of job security provisions is largely inconclusive. We argue that the weak evidence is a consequence of the weak power of statistics used, which is suggested by a dynamic theory of plant-level labor demand that we develop....

The U.S. unemployment insurance (UI) system operates as a federal-state partnership, where states have considerable autonomy to decide on specific UI rules. This has allowed for systematically stricter rules in states with a larger Black population. We study how these differences in state rules...

This paper studies the welfare effects of unemployment insurance (UI) in low-income countries characterized by high levels of informality, weak enforcement of UI claims, and job search frictions. We assess the impact of UI on workers' welfare in the presence of moral hazard and liquidity...

We investigate rewards to R&D in a model where substitute ideas for innovation arrive to random recipients at random times. By foregoing investment in a current idea, society as a whole preserves an option to invest in a better idea for the same market niche, but with delay. Because successive...

We build a model of firm-level innovation, productivity growth and reallocation featuring endogenous entry and exit. A new and central economic force is the selection between high- and low-type firms, which differ in terms of their innovative capacity. We estimate the parameters of the model...

Three sources of gains from trade under monopolistic competition are: (i) new import varieties available to consumers; (ii) enhanced efficiency as more productive firms begin exporting and less productive firms exit; (iii) reduced markups charged by firms due to import competition. The first...

We formulate a two-country model with monopolistic competition and heterogeneous firms to reconsider labor market linkages in open economies. Labor-market imperfections arise by virtue of country-specific real minimum wages. Two principal experiments are considered. First, we show that trade...

So long as the entry and exit of firms using the generic technology sets the price in an industry, one or more price-taking firms can coexist with proprietary technologies yielding more or less substantial quasi-rents to the sunk development costs. Consumer welfare is increased if an innovator...

We review economic arguments for using public policy to accelerate vaccine supply during a pandemic. Rapidly vaccinating a large share of the global population helps avoid economic, mortality, and social losses, which in the case of Covid-19 mounted into trillions of dollars. However,...

This paper explores the practice of mortgage refinancing in a dynamic competitive lending model with risky borrowers and costly default. We show that prepayment penalties improve welfare by ensuring longer-term lending contracts, which prevents the mortgage pools from becoming disproportionately...