Optimal Money Burning: Theory and Application to Corporate Dividend Policy

We explore signaling behavior in settings with a discriminating signal and several costly nondiscriminating ( money burning ) activities. In settings where informed parties have many options for burning money, existing theory provides no basis for selecting one nondiscriminating activity over another. When senders have private information about the costs of these activities, each sender's indifference is resolved, the taxation of a nondiscriminating signal is Pareto improving, and the use of the taxed activity becomes more widespread as the tax rate rises. We apply this analysis to the theory of dividend signaling. The central testable implication of the model is verified empirically.

Control of coherent backscattering by breaking optical reciprocity

Reciprocity is a universal principle that has a profound impact on many areas of physics. A fundamental phenomenon in condensed-matter physics, optical physics and acoustics, arising from reciprocity, is the constructive interference of quantum or classical waves which propagate along time-reversed paths in disordered media, leading to, for example, weak localization and metal-insulator transition. Previous studies have shown that such coherent effects are suppressed when reciprocity is broken. Here we show that by breaking reciprocity in a controlled manner, we can tune, rather than simply suppress, these phenomena. In particular, we manipulate coherent backscattering of light, also known as weak localization. By utilizing a non-reciprocal magneto-optical effect, we control the interference between time-reversed paths inside a multimode fiber with strong mode mixing, and realize a continuous transition from the well-known peak to a dip in the backscattered intensity. Our results may open new possibilities for coherent control of classical and quantum waves in complex systemsComment: Comments are welcom

Factor Price Equality and the Economies of the United States

We develop a methodology for identifying departures from relative factor price equality across regions that is valid under general assumptions about production, markets and factors. Application of this methodology to the United States reveals substantial and increasing deviations in relative skilled wages across labor markets in both 1972 and 1992. These deviations vary systematically with labor markets industry structure both in cross section and over time.Factor Price Equality, Regional Wages, Neoclassical Trade Theory, Labor Market Areas

Multi-Product Firms and Trade Liberalization

This paper develops a general equilibrium model of multi-product firms and analyzes their behavior during trade liberalization. Firm productivity in a given product is modeled as a combination of firm-level "ability" and firmproduct- level "expertise", both of which are stochastic and unknown prior to the firm's payment of a sunk cost of entry. Higher firm-level ability raises a firm's productivity across all products, which induces a positive correlation between a firm's intensive (output per product) and extensive (number of products) margins. Trade liberalization fosters productivity growth within and across firms and in aggregate by inducing firms to shed marginally productive products and forcing the lowest-productivity firms to exit. Though exporters produce a smaller range of products after liberalization, they increase the share of products sold abroad as well as exports per product. All of these adjustments are shown to be relatively more pronounced in countries' comparative advantage industries.heterogeneous firms, endogenous product scope, love of variety, core competency

Multi-Product Firms and Product Switching

This paper examines the frequency, pervasiveness and determinants of product switching among U.S. manufacturing firms. We find that two-thirds of firms alter their mix of five-digit SIC products every five years, that one-third of the increase in real U.S. manufacturing shipments between 1972 and 1997 is due to the net adding and dropping of products by survivors, and that firms are more likely to drop products which are younger and have smaller production volumes relative to other firms producing the same product. The product-switching behavior we observe is consistent with an extended model of industry dynamics emphasizing firm heterogeneity and self-selection into individual product markets. Our findings suggest that product switching contributes towards a reallocation of economic activity within firms towards more productive uses.

Relative Wage Variation and Industry Location

Relative wages vary considerably across regions of the United Kingdom, with skill-abundant regions exhibiting lower skill premia than skill-scarce regions. This paper shows that the location of economic activity is correlated with the variation in relative wages. U.K. regions with low skill premia produce different sets of manufacturing industries than regions with high skill premia. Relative wages are also linked to subsequent economic development: over time, increases in the employment share of skill-intensive industries are greater in regions with lower initial skill premia. Both results suggest firms adjust production across and within regions in response to relative wage differences.

All is not equal.

Theory suggests that market forces should bring the relative pay of skilled workers into line in different regions within a country. Andrew Bernard, Stephen Redding, Peter Schott and Helen Simpson show that this is not the case for the UK and argue that regional industrial policy needs to take this into account.

Relative Wage Variation and Industry Location

Relative wages vary considerably across regions of the United Kingdom, with skill-abundantregions exhibiting lower skill premia than skill-scarce regions. This paper shows that thelocation of economic activity is correlated with the variation in relative wages. U.K. regionswith low skill premia produce different sets of manufacturing industries than regions withhigh skill premia. Relative wages are also linked to subsequent economic development: overtime, increases in the employment share of skill- intensive industries are greater in regionswith lower initial skill premia. Both results suggest firms adjust production across and withinregions in response to relative wage differences.Deindustrialization, Relative Factor Prices, Diversification Cones

Product Choice and Product Switching

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 40% of firm output and almost half of existing products. The theoretical model incorporates heterogeneous firms, heterogeneous products, and ongoing entry and exit. In equilibrium, firm productivity is correlated with product fixed costs, with the most productive firms choosing to make the products with the highest fixed costs. Changes in market structure result in systematic patterns of firm entry/exit and product switching.