2015-22 | With Brzustowski and Wasmer | December 2015
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.
2014-26 | With Branch and Rocheteau | November 2014
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.
2014-24 | With Wasmer and Zeng | September 2014
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.
NBER WP 19207 | With Zhang | July 2014
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.
Endogenous Disasters and Asset Prices
Unpublished Manuscript | With Zhang and Kuehn | October 2013
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).
Solving the DMP Model Accurately
NBER WP 19208 | With Zhang | July 2013
An accurate global algorithm is crucial for quantifying the dynamics of the Diamond-Mortensen-Pissarides model. Loglinearization understates the mean and volatility of unemployment, overstates the unemployment-vacancy correlation, and ignores impulse responses that are an order of magnitude larger in recessions than in booms. Although improving on loglinearization, the second-order perturbation in logs also induces large approximation errors. We demonstrate these insights within the context of Hagedorn and Manovskii (2008). Our quantitative results highlight the extreme importance of accurately accounting for nonlinear dynamics in quantitative macroeconomic studies.
Unemployment, Financial Frictions and the Housing Market
Unpublished Manuscript | With Rocheteau | March 2013
We develop and calibrate a two-sector, search-matching model of the labor market augmented to incorporate a housing market and a frictional goods market. The labor market is divided into a construction sector and a non-housing sector, and there is perfect mobility of unemployed workers across sectors. In the frictional goods market households, who lack commitment, finance random consumption opportunities with home equity loans. The model can generate multiple steady-state equilibria across which housing prices are negatively correlated with unemployment. Relaxing lending standards typically reduces unemployment, but it can have non-monotonic effects on housing prices and supply. It also leads to a reallocation of workers across sectors, the direction of which depends on firm’s market power in the goods market. Quantitatively, we find that innovations that generate an increase in home equity-based borrowing of the same magnitude as the one observed during the 90’s explain a reduction in the steady-state unemployment rate between 1/2 and 1 percentage point depending on the calibration strategy.