The future of social security

We analyze the effect of the projected demographic transition on the political support for social security, and equilibrium outcomes. Embedding a probabilistic-voting setup of electoral competition in the standard OLG model with capital accumulation, we find that intergenerational transfers arise in the absence of altruism, commitment, or trigger strategies. Closed-form solutions predict population ageing to lead to higher social security tax rates, a rising share of pensions in GDP, but eventually lower social security benefits per retiree. The response of equilibrium tax rates to demographic shocks reduces old-age consumption risk. Calibrated to match features of the U.S. economy, the model suggests that, in response to the projected demographic transition, social security tax rates will gradually increase to 16%. Other policies that distort labor supply will become less important; labor supply therefore will rise, in contrast with frequently voiced fears.     

Taxes and stabilization in contemporary macroeconomic models

The role of proportional and procyclic labor income taxes for automatic stabilization with stochastic productivity is analyzed in a contemporary macroeconomic model based on imperfect competition. The importance of short-run nominal wage rigidity for the effectiveness of progressive taxes on labor income for stabilizing output and raising household welfare is examined in a model that yields complete analytical solutions with stochastic output shocks. Increasing the procyclicity of labor income tax rates raises welfare with and without rigid nominal wages in the model economy. With fully flexible prices and wages, a positive covariance between the distortionary tax rate and productivity reduces the volatility of production and employment. This effect disappears under nominal wage rigidity, although progressive taxation can still raise welfare by reducing the distortion caused by a proportional labor tax. With rigid nominal wages and flexible consumer goods prices, payroll taxes levied at rates that rise with output can serve as automatic stabilizers. JEL Code E62 · H20     

Unemployment insurance and capital accumulation

In this paper, I examine a model economy with production, search, and unemployment insurance. The introduction of capital into the economy of Wang and Williamson (J. Monetary Econom. 49(7)(2001)1337) generates the result that optimal replacement ratios are always zero. The result arises from the decline in aggregate activity caused by unemployment insurance: both capital and labor inputs to production fall when benefits rise. Unlike most of the literature, I compute explicitly the cost of the transition path; agents are made better off by switching to a steady state with no unemployment insurance, but the welfare gain is approximately cut in half. Only the very poor and unemployed suffer welfare losses along the transition path. I then briefly investigate the implications of negative replacement ratios.     

Economic Growth and Inequality: Why It Matters and What's Coming Next

This article makes the case that the recent rise in income inequality in OECD countries reflects profound changes in the economic model that previously resulted in growth, prosperity, and social progress during the second half of the last century. The author begins by citing French economist Thomas Piketty's identification of the key driver of rising income inequality as the recent sharp increase in the share of national income going to capital (defined as interest, dividends and other investment returns) and the accompanying decline in the share going to labor (in the form of wages, salaries, pension, and other work‐related benefits). For most of the last 100 years, a successful balance was struck in a majority of OECD countries between the returns to capital and labor. Within the framework of nationally defined economies, labor could effectively advocate for its share of the productivity gains by capital, and governments had the ability to constrain the free movement of capital, set labor compensation standards, and redistribute income through progressive taxation. The author explores how two developments—globalization and the rise of machine intelligence—are disrupting this social contract and reshaping our economy and society. The combination of these two developments, by accelerating the flow of income to capital and away from labor, is eroding the historical relationship between capital, labor, and governments that has long prevailed in most OECD countries. As this happens, we are seeing rising income inequality and the erosion of the middle class, which had been the driver of economic growth for most of the past century. Indeed, the thesis of Piketty's book, Capital in the Twenty‐First Century, is that such an effect may well be taking us back to the pre‐20th century norm of high income inequality and low economic growth. In his closing arguments, the author suggests that avoiding this scenario will be more complicated than simply raising taxes on capital, as proposed by Piketty. It may well require a fundamental rethinking of the role of employment as the primary mechanism for income distribution in society and how we prepare our workforce for an economy and society in which the concept of work will be radically redefined.     

Capital tax competition and social security

The classic capital tax policy externality is studied in the presence of a social security program where both the benefits and taxes depend on wages in an overlapping generations economy with many countries and mobile capital. We study the response and welfare implications of a coordinated capital tax rate increase across countries competing for the mobile tax base on the initial generations, the transition, and the steady state. The tax increase is initially completely capitalized, but some of the burden is shifted to labor on the transition path and in the steady state. Several new welfare effects are uncovered including an effect involving the parameters of the social security program. Sufficient conditions are provided so that all current and future generations are better off from the reform. However, social security may reduce the gain to capital tax reform.     

How much inflation is necessary to grease the wheels?

Tobin's proposition that inflation “greases” the wheels of the labor market is studied using a simple dynamic stochastic general equilibrium model with asymmetric wage adjustment costs. The simulated method of moments is used to estimate the nonlinear model based on its second-order approximation. Optimal inflation is determined by a benevolent government that maximizes the households’ welfare. Econometric results indicate that nominal wages are downwardly rigid and that the optimal level of grease inflation for the U.S. economy is about 0.35% per year, with a 95% confidence interval ranging from 0.04% to 0.87%.     

The Cost of Nominal Rigidity in NNS Models

We present a model with Calvo wage and price setting, capital formation, and estimated rules for government spending and monetary policy. Our model captures many aspects of U.S. data, including the volatility that has been observed in various efficiency gaps. We estimate the cost of nominal rigidity—welfare under flexible wages and prices minus welfare with nominal rigidities—to be as much as 3% of consumption each period. Since there are interest rate rules that virtually eliminate this cost, our model suggests that—contrary to Lucas's (2003) assertion—there is considerable room for improvement in demand management policy.     

Altruism, incomplete markets, and tax reform

We compute the welfare effects of different revenue-neutral tax reforms that eliminate capital income taxation in two general equilibrium models calibrated to the U.S. economy. In our dynastic model, the reform with the largest welfare gain is the one that eliminates all income taxation and increases the consumption tax to 35%; 75% of the population alive at the time of the reform benefit from it. Individuals use intervivos transfers and bequests to redistribute the long-run benefits. In a pure life-cycle economy that lacks this redistribution technology, we find that the same reform would benefit only 9% of the population.     

中国资本产出、资本回报与资本流向之谜--基于劳动力价格扭曲视角北大核心

本文通过建立生产部门的要素买方垄断市场均衡模型,利用1996-2016年中国省级面板数据测算中国劳动力价格扭曲程度,并使用固定效应模型(FE)及面板固定效应的工具变量(IV)估计方法加以分析,从劳动力价格扭曲视角解答了中国资本产出、资本回报与资本流向之谜,即中国经济如何在赶超阶段面临资本深化不断加剧和TFP增长乏力的情况下,依靠劳动力价格扭曲实现低资本产出与高资本回报水平共存,从而维持长期高速资本积累以及优质的资本流向结构。实证研究表明:劳动力价格扭曲降低了资本产出效率,但这并不能掩盖由劳动力向资本方转移的垄断利润对资本回报的直接补贴,因此劳动力价格扭曲对中国维持高资本回报水平起到了重要的支撑作用,并通过高资本回报水平实现了地区资本快速积累,劳动力价格扭曲对资本流向的积极作用还体现在抑制资本"脱实向虚"及吸引外资流入。因此,应正视劳动力价格扭曲在赶超阶段的特殊作用,在矫正扭曲的过程中循序渐进,更积极采取措施规避其对资本回报和资本流向可能产生的不利影响。     

On the optimal progressivity of the income tax code

This paper computes the optimal progressivity of the income tax code in a dynamic general equilibrium model with household heterogeneity in which uninsurable labor productivity risk gives rise to a nontrivial income and wealth distribution. A progressive tax system serves as a partial substitute for missing insurance markets and enhances an equal distribution of economic welfare. These beneficial effects of a progressive tax system have to be traded off against the efficiency loss arising from distorting endogenous labor supply and capital accumulation decisions.Using a utilitarian steady state social welfare criterion we find that the optimal US income tax is well approximated by a flat tax rate of 17.2% and a fixed deduction of about $9,400. The steady state welfare gains from a fundamental tax reform towards this tax system are equivalent to 1.7% higher consumption in each state of the world. An explicit computation of the transition path induced by a reform of the current towards the optimal tax system indicates that a majority of the population currently alive (roughly 62%) would experience welfare gains, suggesting that such fundamental income tax reform is not only desirable, but may also be politically feasible.     

Downward wage rigidity and business cycle asymmetries

The growth rates of wages, unemployment and output of a number of OECD countries have a strongly skewed distribution. In this paper we analyze to what extent downward wage rigidities can explain these empirical business cycle asymmetries. To this aim, we introduce asymmetric wage adjustment costs in a New-Keynesian DSGE model with search and matching frictions in the labor market. Increasing wages is less costly than cutting them. It follows that wages increase relatively fast and thus limit vacancy posting and employment creation, but they decline more slowly, leading to a strong reduction in vacancies and employment. The presence of downward wage rigidities strongly improves the fit of the model to the observed skewness of labor market variables and the relative length of expansions and contractions in the output and the employment cycles. The asymmetry also explains the differing transmission of positive and negative monetary policy shocks from wages to inflation.     

Wage rigidities and jobless recoveries

Real wage rigidities cause jobless recoveries. Suppose that a one-time shock reduces the capital stock below trend. If wages are flexible, they decline and employment increases at the moment of the shock, before both revert back to normal levels as the economy grows back to trend. If wages are completely rigid and the labor market is otherwise frictionless, the shock causes a proportional and permanent decline in employment, capital, output, consumption, and investment relative to trend. In a search model with rigid wages, the shock causes a persistent but not permanent decline in these economic outcomes, a jobless recovery.     

The anticipated real interest rate,capital utilization and the cyclical pattern of real wages

This paper develops a channel through which increases in anticipated real interest rates can be ‘expansionary’ for current aggregate labor demand and current output supply. The key feature of the model is the introduction of a user cost of capital utilization which confronts the firm with the intertemporal problem of the optimal choices of capital utilization and depreciation. The resulting variation in capital utilization and capital services in response to fluctuations in the real rate of interest shifts the marginal product of labor and, thus, the demand for labor at the same time and in the same direction that Lucas-Rapping real interest rate effects operate on labor supply. The complete model places no a priori restrictions on the cyclical pattern of real wages, thus avoiding the countercyclical real wage prediction made by Keynes and various classical writers that is rejected by the data. Estimates of a labor demand schedule for the annual U.S. data reveal a significantly positive real interest rate effect.     

Politico-economic consequences of rising wage inequality

This paper uses a dynamic political economy model to evaluate whether the observed rise in wage inequality and decrease in median to mean wages can explain some portion of the relative increase in transfers to low earnings quintiles and relative increase in effective tax rates for high earnings quintiles in the U.S. over the past several decades. Specifically, we assume that households have uninsurable idiosyncratic labor efficiency shocks and consider policy choices by a median voter which are required to be consistent with a sequential equilibrium. We choose the transition matrix to match observed mobility in wages between 1978 and 1979 in the panel study of income dynamics (PSID) data set and then evaluate the response of social insurance policies to a new transition matrix that matches the observed mobility in wages between 1995 and 1996 and is consistent with the rise in wage inequality and the decrease in median to mean wages between 1979 and 1996. We deal with the problem that policy outcomes affect the evolution of the wealth distribution (and hence prices) by approximating the distribution by a small set of moments. We contrast these numbers with those from a sequential utilitarian mechanism, as well as mechanisms with commitment.     

美国货币政策溢出效应、中国资产价格波动与资本账户管理

本文以2016年美国加息事件为背景,研究美国货币政策对中国资本流动、资产价格和宏观经济的影响。基于小国开放动态随机一般均衡模型,本文梳理了美国货币政策溢出效应的具体传导渠道,发现国外利率升高后,资本流动具有外部性,导致国内资产价格下跌,其通过金融加速器进一步使国内投资下降、资产价格进一步下跌,从而使得国内资产预期回报进一步下降,加剧资本外流。基于政策和福利分析,本文发现资本账户管理可以有效缓解国外利率冲击对经济波动的影响,同时会提高货币政策的独立性,但也会影响国民财富的最优配置。因此,最优的资本账户管理应同时兼顾宏观审慎和效率两个方面。     

Optimal taxation with home production

Optimal taxes for Europe and the U.S. are derived in a realistically calibrated model in which agents buy consumption goods and services and use home capital and labor to produce household services. The optimal tax rate on services is substantially lower than the tax rate on goods. Specifically, the planner cannot tax home production directly and instead lowers the tax rate on market services to increase the relative price of home production. The optimal tax rate on the return to home capital is strictly positive and the welfare gains from switching to optimal taxes are large.     

A quantitative assessment of the decline in the U.S. current account

Low frequency changes in the U.S. current account can be understood in terms of the influence of differences in productivity growth rates across time and across countries using standard growth theory. In particular, the secular decline is primarily driven by the increase in the U.S. TFP growth rate relative to its trading partners. Differences in population growth rates or fiscal policy have no significant effects on the low frequency changes in the U.S. current account.     

Quantifying the risk-sharing welfare gains of social security

The welfare effects of intergenerational risk sharing through a pay-as-you-go social security system that is efficiently indexed to wages or interest rates are quantified. Comparing steady states, there are large welfare gains of being born into an economy with efficient risk sharing as compared to the current U.S. system. Efficient policy involves an increasingly risky net of tax income over the life cycle. When adjustment to steady state is taken into account, the welfare gains largely turn negative. The results are also compared and contrasted to the first best allocation.     

Productivity,restructuring, and the gains from takeovers

This paper investigates how takeovers create value. Using plant-level data, I show that acquirers increase targets' productivity through more efficient use of capital and labor. Acquirers reduce capital expenditures, wages, and employment in target plants, though output is unchanged. Acquirers improve targets' investment efficiency through reallocating capital to industries with better investment opportunities. Moreover, changes in productivity help explain the merging firms' announcement returns. The combined announcement returns are driven by improvements in target's productivity. Targets with greater productivity improvements receive higher premiums. These results provide some first empirical evidence on the relation between productivity and stock returns in takeovers.     

Markups and the Welfare Cost of Business Cycles: A Reappraisal

Gali, Gertler, and Lopez‐Salido (2007) recently show quantitatively that fluctuations in the efficiency of resource allocation do not generate sizable welfare costs. In their economy, which is distorted by monopolistic competition in the steady state, we show that they underestimate the welfare cost of these fluctuations by ignoring the negative effect of aggregate volatility on average consumption and leisure. As monopolistic suppliers, both firms and workers aim to preserve their expected markups; the interaction between aggregate fluctuations and price‐setting behavior results in average consumption and employment levels that are lower than their counterparts in the flexible‐price economy. This level effect increases the efficiency cost of business cycles. It is all the more sizable with the degree of inefficiency in the steady state, lower labor–supply elasticities, and when prices instead of wages are rigid.