Firms differ in their vulnerability to new entrants to their industries. Recent research has shown the costs of entry to have varied over time, being low before the early 80s and having risen since. In a model with monopolistic competition, fixed costs, and heterogeneous markups, I show that...

Extending Milgrom and Roberts (1982) we present an infinite horizon entry model, where the incumbent(s) may use the current price to signal its strength to deter entry. We show that, due to the importance of entrants' types on the post-entry duopoly/oligopoly profits, the incumbent(s) may want...

Our simple model features agents heterogeneous in skill and risk aversion, incomplete financial markets, and redistributive taxation. In equilibrium, agents become entrepreneurs if their skill is sufficiently high or risk aversion sufficiently low. Under heavier taxation, entrepreneurs are more...

Ljungqvist and Sargent (2017) (LS) show that unemployment fluctuations can be understood in terms of a quantity they call the "fundamental surplus." However, their analysis ignores risk premia, a force that Hall (2017) shows is important in understanding unemployment fluctuations. We show how...