Efficiency and Labor Market Dynamics in a Model of Labor Selection (with Christian Merkl)
International Economic Review, 2016. Vol. 57, p. 1371-1404.
This article characterizes efficient labor-market allocations in a labor selection model. The model's crucial aspect is cross-sectional heterogeneity for new job contacts, which leads to an endogenous selection threshold for new hires. With cross-sectional dispersion calibrated to microeconomic data, 40 percent of empirically-relevant fluctuations in the job-finding rate arise, which contrasts with results in an efficient search and matching economy. The efficient selection model's results hold in partial and general equilibrium, as well as with sequential search.
Review of Economic Dynamics, 2016. Vol. 20, p. 111-131.
I characterize cyclical fluctuations in the cross-sectional dispersion of firm-level productivity. Using the micro-estimated dispersion, or "risk," stochastic process as an input to a baseline small-scale financial accelerator model, I assess how well the model reproduces cyclical movements in both real and financial conditions of the economy. In the model, risk shocks calibrated to micro data lead to empirically-relevant steady-state leverage, a financial measure typically thought to be closely associated with real activity. In terms of aggregate quantities, pure risk shocks in the small-scale general equilibrium model account for a notable share of GDP fluctuations -- roughly 5%. The volatility of the risk process I measure using micro data is, remarkably, not very different compared to recent estimates of risk shocks based on medium- or large-scale models using macroeconomic data. These seemingly contrasting starting points for measuring risk shocks do not imply any dichotomy at the core of a popular class of DSGE financial frictions models. Rather, it is the particular transmission channels in financial-frictions models -- whether small scale or medium scale -- that are critical for aggregate quantity fluctuations to arise based on risk shocks.
Optimal Fiscal and Monetary Policy in Customer Markets (with David M. Arseneau, Ryan Chahrour, and Alan Finkelstein Shapiro)
Journal of Money, Credit, and Banking, 2015. Vol. 47, p. 617-672.
This paper presents a model in which some goods trade in "customer markets." In these markets, advertising plays a critical role in facilitating long-lived relationships. We estimate both policy and non-policy parameters of the model (which includes New-Keynesian frictions) on U.S. data, including advertising expenditures. The estimated parameters imply a large congestion externality in the pricing of customer market goods. This pricing inefficiency motivates the analysis of optimal policy. When the planner has access to a complete set of taxes and chooses them optimally, fiscal policy eliminates the externalities with large adjustments in the tax rates that operate directly in customer markets; labor tax volatility remains low. If available policy instruments are constrained to the interest rate and labor tax, then the latter displays large and procyclical fluctuations, while the implications for monetary policy are largely unchanged from the model with no customer markets.
Journal of Economic Dynamics and Control, 2013. Vol. 37, p. 2882-2912.
We study the role of agency frictions and costly external finance in cyclical labor market dynamics, with a focus on how credit-market frictions may amplify aggregate TFP shocks. The main result is that aggregate TFP shocks lead to large fluctuations of labor market quantities if the model is calibrated to the empirically-observed countercyclicality of the finance premium. A financial accelerator mechanism thus amplifies labor market fluctuations. In contrast, if the finance premium is procyclical, which the model can be parameterized to accomodate, amplification is absent, and labor-market fluctuations display the Shimer (2005) puzzle. The cyclicality of the finance premium in the model is governed by the degree of "technology spillover" from aggregate TFP to firms' idiosyncratic productivity. If positive shocks to aggregate TFP on average improve firms' idiosyncratic productivity, a correlation that has support in firm-level studies of productivity, equilibrium labor-market fluctuations are amplified through two channels. One channel is a direct productivity channel --- firms are on average more productive for a given size positive aggregate shock than if there were no productivity correlation. The second channel is a financial conditions channel, through which improved firm-level productivity reduces the risk of bankruptcy, which dampens the external finance premium and lowers firms' financing costs. Both channels induce firms to expand activity, including hiring, more sharply than if there were no productivity correlation. Sixty percent of the model's amplification comes through the financing channel, and 40 percent of the model's amplification comes through the productivity channel.
Tax Smoothing in Frictional Labor Markets (with David M. Arseneau)
Journal of Political Economy, 2012. Vol. 120, p. 926-985.
The optimality of tax smoothing is re-examined from the point of view of frictional labor markets. The main result is that, in a calibrated matching model that generates empirically-relevant labor-market fluctuations conditional on exogenous fiscal policy, the Ramsey-optimal policy calls for extreme labor-tax-rate volatility. Purposeful tax volatility induces dramatically smaller, but efficient, fluctuations of labor markets by keeping distortions constant over the business cycle. We relate the results to standard Ramsey theory by developing welfare-relevant concepts of efficiency and distortions that take into account primitive matching frictions and that can be applied to any general-equilibrium matching model. Although the basic Ramsey principles of "wedge-smoothing" and zero intertemporal distortions hold in a matching framework, whether or not they imply tax smoothing depends on whether wages are set effiiciently.
Optimal Fiscal and Monetary Policy When Money is Essential (with S. Boragan Aruoba)
Journal of Economic Theory, 2010. Vol. 145, p. 1618-1647.
We study optimal fiscal and monetary policy in an environment where explicit frictions give rise to valued money, making money essential in the sense that it expands the set of feasible trades. The two main results are that the Friedman Rule is typically not optimal, and the long-run capital income tax is not zero. Neither of these results is due to any incompleteness of the tax system, as can sometimes occur in standard Ramsey analysis. Rather, by developing a precise notion of margins of adjustment using standard concepts of MRS and MRT, we show that the tax system in our model is complete. The need to distort cash-intensive activity in some sense causes a nonzero capital tax in our model. This deep connection between monetary issues and fiscal policy is in contrast to existing models of jointly-optimal fiscal and monetary policy, in which the monetary aspects of the economic environment have little to do with capital taxation prescriptions. Taken together, these findings reframe some conventional wisdom from baseline Ramsey models.
PDF file, March 2010 version PDF file, Expanded version, September 2006
Does the Timing of the Cash-in-Advance Constraint Matter for Optimal Fiscal and Monetary Policy?
Macroeconomic Dynamics, 2009. Vol. 3, p. 133-150.
We quantitatively demonstrate that the precise timing of financial markets and goods markets in a flexible-price cash good/credit good model does not matter for the baseline results in the Ramsey literature on optimal fiscal and monetary policy. This result is reassuring because Ramsey analysis, in the tradition begun by Lucas and Stokey (1983) and Chari, Christiano, and Kehoe (1991), has been applied to a quickly-expanding rich class of DGSE models recently, making it important to know whether models based on these original structures have been pursuing a mirage. In the original models, the timing is such that nominal money holdings are freely-adjustable in response to shocks in the period in which they will be used to purchase consumption. We alter this timing convention so that nominal balances cannot be adjusted in the period they will be used --- the timing assumption of Svensson (1985) --- to study how sensitive the baseline results are to this slight, and ultimately ad-hoc, modification. We find that Ramsey-optimal inflation continues to display very high variability just as in the original models. The basic intuition for the result is that, no matter the timing of markets, inflation variability creates no relative price distortions. Thus, interpretation of results from the recent spate of Ramsey studies, which have had as a primary motivation the determination of the optimal degree of inflation stabilization in the presence of various features and frictions in the economy, is not blurred by the choice of cash/credit timing.
Optimal Fiscal and Monetary Policy with Costly Wage Bargaining (with David M. Arseneau)
Journal of Monetary Economics, 2008. Vol. 55, p. 1401-1414.
Costly nominal wage adjustment has received renewed attention in the design of optimal policy. In this paper, we embed costly nominal wage adjustment into the modern theory of frictional labor markets to study optimal fiscal and monetary policy. The main result is that the optimal rate of price inflation is quite volatile despite the presence of nominal wage rigidities. This finding contrasts with results obtained in standard sticky-wage models, which employ neoclassical labor markets at their core. In addition, the tax-smoothing result that lies at the heart of optimal policy prescriptions in standard Ramsey models does not carry over to a search and bargaining environment. Both results stem from a common source in our model. Shared rents associated with the formation of long-term employment relationships imply that the optimal policy entails fluctuations in after-tax real wages much larger than in models with neoclassical labor markets, in which no such rent-sharing margin exists. The results demonstrate that the level at which nominal wage rigidity is modeled --- whether simply layered on top of a neoclassical market or articulated in the context of an explicit relationship between workers and firms --- can matter a great deal for policy recommendations.
This short paper generalizes the consumption externalities model of Dupor and Liu (AER, 2003) to allow for externalities of different magnitudes and directions (positive and negative) in different goods.
Optimal Inflation Persistence: Ramsey Taxation with Capital and Habits
Journal of Monetary Economics, 2007. Vol. 54, p. 1809-1836.
Ramsey models of fiscal and monetary policy featuring time-separable preferences and a fixed supply of capital predict highly volatile inflation with no serial correlation. In this paper, we show that an otherwise-standard Ramsey model that incorporates capital accumulation and habit persistence predicts highly persistent inflation. The result depends on increases in either the ability to smooth consumption or the preference for doing so. The effect operates through the Fisher relationship: a smoother profile of consumption implies a more persistent real interest rate, which in turn implies persistent optimal inflation. Our work complements a recent strand of the Ramsey literature based on models with nominal rigidities. In these latter models, inflation volatility is lower than in the baseline model but continues to exhibit little persistence. We quantify the effects of habit and capital on inflation persistence and also relate our findings to recent work on optimal fiscal policy with incomplete markets.
Optimal Fiscal and Monetary Policy with Sticky Wages and Sticky Prices
Review of Economic Dynamics, 2006. Vol. 9, p. 683-714.
We determine the optimal degree of price inflation volatility when nominal wages are sticky and the government uses state-contingent inflation to finance government spending. We address this question in a well-understood Ramsey model of fiscal and monetary policy, in which the benevolent planner has access to labor income taxes, nominally risk-free debt, and money creation. Our main result is that sticky wages alone make price stability optimal in the face of shocks to the government budget, to a degree quantitatively similar as sticky prices alone. Key for our results is an equilibrium restriction between nominal price inflation and nominal wage inflation that holds trivially in a Ramsey model featuring only sticky prices. Our results thus show that when nominal wages are sticky, setting real wages as close as possible to their efficient path is a more important goal of optimal monetary policy than is financing innovations in the government budget via state-contingent inflation. A second important result is that the nominal interest rate can be used to indirectly tax the rents of monopolistic labor suppliers. Taken together, our results uncover features of Ramsey fiscal and monetary policy in the presence of a type of labor market imperfection that is widely-believed to be important.
Optimal Fiscal Policy with Labor Selection (with Wolfgang Lechthaler and Christian Merkl)
This paper characterizes long-run and short-run optimal fiscal policy in the labor selection framework. Quantitatively, the volatility of the labor income tax rate is orders of magnitude larger than the "tax-smoothing" results based on Walrasian labor markets, but is a few times smaller than the results based on search and matching labor markets. To understand the results, we develop a welfare-relevant analytic concept of "tightness" for the selection model. This concept of tightness is the source of the decentralized economy's inefficient wage premia between the average newly-hired worker and the marginal newly-hired worker. Compared to the well-known concept of "labor-market tightness" in the search and matching literature, this new concept of tightness plays a highly similar role, and, like in the matching model, is crucial for understanding efficiency and optimal policy.
Searching for Wages in an Estimated Labor Matching Model (with Ryan Chahrour and Tristan Potter)
We estimate a real business cycle economy with search frictions in the labor market in which the latent wage follows a non-structural ARMA process. The estimated model does an excellent job matching a broad set of quantity data and wage indicators. Under the estimated process, wages respond immediately to shocks but converge slowly to their long-run levels, inducing substantial variation in labor's share of surplus. These results are not consistent with either a rigid real wage or flexible Nash bargaining. Despite inducing a strong endogenous response of wages, neutral shocks to productivity account for the vast majority of aggregate fluctuations in the economy, including labor market variables.
Optimal Fiscal Policy with Endogenous Product Variety (with Fabio Ghironi)
We study Ramsey-optimal fiscal policy in an economy in which product creation is the result of forward-looking investment decisions by firms. There are two main results. First, depending on the particular form of variety aggregation, firms' dividend payments may be either subsidized or taxed in the long run. This policy balances monopoly incentives for product creation with the welfare benefit of product variety. In the most empirically relevant form of variety aggregation, socially efficient outcomes entail a substantial tax on dividend income, removing the incentive for over-accumulation of capital, which takes the form of the stock of products. Similar intuitions determine the optimal setting of long-run producer entry subsidies. Second, optimal policy induces dramatically smaller, but efficient, fluctuations of both capital and labor markets than in a calibrated exogenous policy. Decentralization requires zero intertemporal distortions and constant static distortions over the cycle. The results relate to Ramsey theory, which we show by developing welfare-relevant concepts of efficiency that take into account product creation. The results on optimal entry subsidies provide guidance for the study of product market reforms in dynamic macro models.
Labor Force Participation and General Equilibrium Efficiency in Search and Matching Models (with David M. Arseneau)
We provide a characterization of general-equilibrium efficiency in the standard labor search and matching framework. The efficiency condition builds on the well-known Hosios condition for labor-market efficiency, which is derived in partial-equilibrium models of the labor market. What makes our analysis general equilibrium is that we consider a labor force participation decision, a margin absent in many models of the labor market. The efficiency condition we develop has a simple interpretation in terms of marginal rates of substitution and marginal rates of transformation; it also provides a criterion by which general equilibrium search models can measure the attainment of efficiency, as well as provides a new basis for empirical tests of labor-market efficiency.
Optimal Capital Taxation in an Economy with Capital Allocation Frictions (with David M. Arseneau and Andre Kurmann)
We study optimal capital-income taxation in an economy in which search frictions in physical capital markets give rise to flows of economic profit. These profit flows are necessary compensation for sunk search costs of entry into the capital market. Viewed in this way, profits are quasi-rents. At any point in time, however, profit flows from existing matches can also be viewed as pure rents. Whether a Ramsey government considers profit flows as pure rents or as quasi-rents is crucial for whether and to what extent capital-income taxation should be used to tax profits. We prove that if the government treats profits as quasi-rents, the canonical long-run zero-capital-tax prescription arises. If profits are instead treated as pure rents, the long-run optimal capital-income tax is non-zero, with a calibrated version of this economy featuring a capital-income tax rate of over 30 percent. The sharply contrasting results are not due to any lack of commitment. Rather, because profit flows are explicitly linked to free-entry conditions, a Ramsey government has an economic basis for adopting either the pure-rent view or the quasi-rent view. In the long run, however, the quasi-rent equilibrium is welfare-superior.
Money and Optimal Capital Taxation (with S. Boragan Aruoba)
In existing models of jointly-optimal fiscal and monetary policy, the monetary aspects of the economic environment have little to do with capital taxation prescriptions. Instead, the capital-taxation prescriptions of the underlying purely real economy in such models carry over unchanged, qualitatively and very nearly quantitatively, to the monetary economy. In this paper, we employ a micro-founded model of money in order to more meaningfully connect optimal fiscal and monetary policy, with a particular focus on optimal capital taxation. Our main result is that deep-rooted frictions underlying monetary trade in and of themselves provide a rationale for nonzero capital taxation --- specifically, for capital subsidies. Optimal capital subsidies arise in versions of our model where monetary trades lead to capital holdup problems --- in which case the prescription to subsidize capital follows readily --- as well as versions of our model where holdup problems are absent. The latter result especially highlights the unique connection between fiscal and monetary policy our model articulates because the underlying purely real economy in our model features zero capital taxation. Connecting our results with some other recent advances in optimal capital taxation, we prove that for some versions of our environment, capital-income subsidies are consistent with zero intertemporal distortions. Our main conclusion is that capital-tax policy can fundamentally be driven by monetary issues. PDF file August 2008 version
Competitive Search Equilibrium in a DSGE Model (with David M. Arseneau)
We show how to implement the concept of competitive search equilibrium in a fully-specified DSGE environment. Competitive search equilibrium, an equilibrium concept well-understood in labor market theory, offers an alternative to the commonly-used Nash bargaining in search-based macro models. Our simulation-based results show that business cycle fluctuations under competitive search equilibrium are virtually identical to those under Nash bargaining for a broad range of calibrations of Nash bargaining power. We also prove that business cycle fluctuations under competitive search equilibrium are identical to those under Nash bargaining restricted to the popularly-used Hosios condition for search efficiency. This latter result extends the efficiency properties of competitive search equilibrium to a DSGE environment. Our results thus provide a foundation for researchers interested in studying business cycle fluctuations using search-based environments to claim that the sometimes-awkward assumption of bargaining per se does not obscure interpretation of results.
Bargaining, Fairness, and Price Rigidity in a DSGE Environment (with David M. Arseneau)
A growing body of evidence suggests that an important reason why firms do not change prices nearly as much as standard theory predicts is out of concern for disrupting ongoing customer relationships because price changes may be viewed as "unfair." Existing models that try to capture this concern regarding price-setting are all based on goods markets that are fundamentally Walrasian. In Walrasian goods markets, transactions are spot, making the idea of ongoing customer relationships somewhat difficult to understand. We develop a simple dynamic general equilibrium model of a search-based goods market to make precise the notion of a customer as a repeat buyer at a particular location. In this environment, the transactions price plays a distributive role as well as an allocative role. We exploit this distributive role of prices to explore how concerns for fairness influence price dynamics. Using pricing schemes with bargaining-theoretic foundations, we show that the particular way in which a "fair" outcome is determined matters for price dynamics. The most stark result we find is that complete price stability can arise endogenously. These are issues about which models based on standard Walrasian goods markets are silent.
Ramsey Meets Hosios: The Optimal Capital Tax and Labor Market Efficiency (with David M. Arseneau)
This paper studies optimal capital income taxation in an economy where labor markets are subject to search and matching frictions. We prove that, provided the government is constrained to capital and labor income taxation, inefficienc labor force participation leads to a non-zero optimal capital tax in the long run. In a calibration version of the model, the optimal capital income tax is very sensitive to how far above or below the participation rate is from its efficient level. Thus, even seemingly small inefficiencies in participation may call for large capital income taxes (or subsidies).