This paper studies the optimal sharing of value added between consumers, producers, and labor. We first define a constrained optimum. We then compare it with the decentralized allocation. They coincide when the price maximizes the expected marginal revenue of the firm in the goods market, an outcome of the competitive search equilibrium, and when the wage exactly offsets the congestion externality of firm entry in the labor market, which is the traditional Hosios condition. Under price and wage bargaining, this allocation is achieved under a double Hosios condition combining the logic of competitive search and Hosios efficiency. The consumer receives a share of the goodsmarket trading surplus equal to the amount of externality occasioned by its search activity and the worker receives a share of the labor match surplus to offset the externality of firm entry in the matching process. A calibration of the model to the US economy indicates that the labor market is near efficient, and free-entry of consumers leads to excess excess consumer market power in setting prices. Restoring efficiency leads to a modest change in welfare.
A search and matching model, when calibrated to the mean and volatility of unemployment in the postwar sample, can potentially explain the unemployment crisis in the Great Depression. The limited responses of wages from credible bargaining to labor market conditions, along with the congestion externality from matching frictions, cause the unemployment rate to rise sharply in recessions but decline gradually in booms. The frequency, severity, and persistence of unemployment crises in the model are quantitatively consistent with U.S. historical time series. The welfare gain from eliminating business cycle fluctuations is large.
Published Articles (Refereed Journals and Volumes)
Endogenous Disasters and Asset Prices
Forthcoming in American Economic Review | With Zhang and Kuehn
Frictions in the labor market are important for understanding the equity premium in the financial market. We embed the Diamond-Mortensen-Pissarides search framework into a dynamic stochastic general equilibrium model with recursive preferences. The model produces realistic equity premium and stock market volatility, as well as a low and stable interest rate. The equity premium is countercyclical, and forecastable with labor market tightness, a pattern we confirm in the data. Intriguingly, three key ingredients (small profits, large job flows, and matching frictions) in the model combine to give rise endogenously to rare disasters a la Rietz (1988) and Barro (2006).
Disentangling Goods, Labor, and Credit Market Frictions in Three European Economies
Forthcoming in Labour Economics | With Brzustowski and Wasmer
We build a flexible model with search frictions in three markets: credit, labor, and goods markets. We then apply this model (called CLG) to three different economies: a flexible, finance-driven economy (the UK), an economy with wage moderation (Germany), and an economy with structural rigidities (Spain). In the three countries, goods and credit market frictions play a dominant role in entry costs and account for 75% to 85% of total entry costs. In the goods market, adverse supply shocks are amplified through their propagation to the demand side, as they also imply income losses for consumers. This adds up to, at most, an additional 15% to 25% to the impact of the shocks. Finally, the speed of matching in the goods market and the credit market accounts for a small fraction of unemployment: Most of the variation in unemployment comes from the speed of matching in the labor market.
An accurate global projection algorithm is critical for quantifying the basic moments of the Diamond-Mortensen-Pissarides model. Log linearization understates the mean and volatility of unemployment, but overstates the volatility of labor market tightness and the magnitude of the unemployment–vacancy correlation. Log linearization also understates the impulse responses in unemployment in recessions, but overstates the responses in the market tightness in booms. Finally, the second-order perturbation in logs can induce severe Euler equation errors, which are often much larger than those from log linearization.
We develop a two-sector search-matching model of the labor market with imperfect mobility of workers, augmented to incorporate a housing market and a frictional goods market. Homeowners use home equity as collateral to finance idiosyncratic consumption opportunities. A financial innovation that raises the acceptability of homes as collateral raises house prices and reduces unemployment. It also triggers a reallocation of workers, with the direction of the change depending on firms’ market power in the goods market. A calibrated version of the model under adaptive learning can account for house prices, sectoral labor flows, and unemployment rate changes over 1996–2010.
The renewal of interest in macroeconomic theories of search frictions in the goods market requires a deeper understanding of the cyclical properties of the intensive margins in this market. We review the theoretical mechanisms that promote either procyclical or countercyclical movements in time spent searching for consumer goods and services, and then use the American Time Use Survey to measure shopping time through the Great Recession. Average time spent searching declined in the aggregate over the period 2008-2010 compared to 2005-2007, and the decline was largest for the unemployed who went from spending more to less time searching for goods than the employed. Cross-state regressions point towards a procyclicality of consumer search in the goods market. At the individual level, time allocated to different shopping activities is increasing in individual and household income. Overall, this body of evidence supports procyclical consumer search effort in the goods market and a conclusion that price comparisons cannot be a driver of business cycles.
Macroeconomic Dynamics in a Model of Goods, Labor and Credit Market Frictions
Journal of Monetary Economics 72, May 2015 | With Wasmer
This paper shows that goods-market frictions drastically change the dynamics of the labor market, bridging the gap with the data both in terms of persistence and volatility. In a DSGE model with three imperfect markets – goods, labor and credit – we find that credit- and goods-market imperfections are substitutable in raising volatility. Goods-market frictions are however unique in generating persistence. The two key mechanisms generating autocorrelation in growth rates and the hump-shaped pattern in the response to productivity shocks are related to the goods market: i) countercyclical dynamics of goods market tightness and prices, which alter future profit flows and raise persistence and ii) procyclical search effort in the goods market, by either consumers, firms or both, raises both amplification and persistence. Expanding our knowledge of goods market frictions is thus needed for a full account of labor market dynamics.
Credit, Vacancies and Unemployment Fluctuations
Review of Economic Dynamics 17(2), April 2014, lead article
Propagation in equilibrium models of search unemployment is altered when vacancy costs require some external financing on frictional credit markets. The easing of financing constraints during an expansion as firms accumulate net worth reduces the opportunity cost for resources allocated to job creation. The dynamics of market tightness are affected by (i) a cost channel, increasing the incentive to recruit for a given benefit from a new hire, and (ii) a wage channel, whereby firms’ improved bargaining position limits the upward pressure of market tightness on wages. Agency related credit frictions endogenously generate persistence in the dynamics of labor-market tightness, and have a moderate endogenous effect on amplification.
The financial crisis of 2008 was followed by sharp contractions in aggregate output and The financial crisis of 2008 was followed by sharp contractions in aggregate output and employment and an unusual increase in aggregate total factor productivity (TFP). This paper attempts to explain these facts by modeling the creation and destruction of jobs in the presence of heterogeneity in firm productivity and frictional credit and labor markets. The aggregate level of TFP is determined by both the underlying distribution of firm productivity and the structures of the credit and labor markets. Adverse shocks to credit markets destroy the least productive jobs and slow job creation, thus raising aggregate TFP and unemployment, and reducing output.
The Cyclical Volatility of Labor Markets under Frictional Financial Market
American Economic Journal: Macroeconomics 5(1), January 2013 | With Wasmer
We provide a dynamic extension of an economy with search on credit and labor markets (Wasmer and Weil, 2004). Financial frictions create volatility: they add an additional, almost acyclical, entry cost to procyclical job creation costs, thus increasing the elasticity of labor market tightness to productivity shocks by a factor of 5 to 8, compared to a matching economy with perfect financial markets. We characterize a dynamic financial multiplier, that is increasing in total financial costs and minimized under a credit market Hosios-Pissarides rule. Financial frictions are an element of the solution to the volatility puzzle.