We develop a two-country model of endogenous innovation and imitation in order to study the interactions between these two processes. Firms in the North race to bring out the next generation of a set of technology-intensive products. Each product potentially can be improved a countably infinite...

This paper develops a model of endogenous product selection by firms. The theory is motivated by new evidence we present on the importance of product switching by U.S. manufacturers. Two-thirds of continuing firms change their product mix every five years, and product switches involve more than...

This paper explores role of product adding and dropping within manufacturing firms over the business cycle. While a substantial body of work has explored the importance of the extensive margins of firm entry and exit in employment and output flows, only recently has research begun to examine the...

We investigate how firms adapt to trademark protection, an extensively used but underexamined form of IP protection, by exploring a historical precedent: China's trademark law of 1923---an unanticipated and disapproved response to end foreign privileges in China. By exploiting a unique, newly...

Product redesigns happen across virtually all types of products. While there is substantial evidence that new varieties of goods increase welfare, there is little evidence on the effect of product redesigns. We develop a model of redesign and exit decisions in a dynamic oligopoly model (a la...

We build a theoretical model of multi-product firms that highlights how competition across market destinations affects both a firm's exported product range and product mix. We show how tougher competition in an export market induces a firm to skew its export sales towards its best performing...

This paper proposes a new measure of technological obsolescence using detailed patent data. Using this measure, we present two sets of results. First, firms' technological obsolescence foreshadows substantially lower growth, productivity, and reallocation of capital. This finding applies mainly...

In this paper, we argue that actuarial valuation of annuity benefit streams is theoretically inconsistent with the assumption of pure lifecycle motives. Instead, we show that the simple discounted value of future benefits (ignoring the possibility of death) is often a good approximation to the...

Recent theoretical work predicts that an important margin of adjustment to deregulation or trade reforms is the reallocation of output within firms through changes in their product mix. Empirical work has accordingly shifted its focus towards multi-product firms and their product mix decisions....

In this paper we revisit two well-known facts regarding lifecycle expenditures. The first is the familiar "hump" shaped lifecycle profile of nondurable expenditures. We document that the behavior of total nondurables masks surprising heterogeneity in the lifecycle profile of individual...