Risky human capital and deferred capital income taxation

We study the structure of optimal wedges and capital taxes in a dynamic Mirrlees economy with endogenous distribution of skills. Human capital is a private, stochastic state variable that drives the skill process of each individual. Building on the findings of the labor literature, we construct a tractable life-cycle model of human capital evolution with risky investment and stochastic depreciation. In this setting, we demonstrate the optimality of (a) a human capital premium, i.e., an excess return on human capital relative to physical capital, (b) a large intertemporal wedge early in the life-cycle, and (c) a non-zero intratemporal wedge even at the top of the skill distribution at all dates except the last date in the life-cycle. The main implication for the structure of optimal linear capital taxes is the necessity of deferred taxation of physical capital. The average marginal tax rate on physical capital held in every period is zero in present value. However, expected capital tax payments do not equal zero in every period. Necessarily, agents face negative expected capital tax payments early in the life-cycle and positive expected capital tax payments late in the life-cycle.     

The existence, uniqueness, and optimality of the terminal wealth depletion time in life-cycle models of saving under uncertain lifetime and borrowing constraint

In life-cycle models of saving under uncertain lifetime and borrowing constraint, the consumer's wealth must be depleted before the maximum lifetime. This paper investigates the existence, uniqueness, and optimality of the terminal wealth depletion time. It is proved that the optimal terminal wealth depletion time, if such exists, must be unique. If the equation that determines the optimal terminal wealth depletion has multiple solutions, then the location of the optimal solution will depend on the configuration of the solutions. An optimality test is developed to verify whether a candidate solution for the terminal wealth depletion time is indeed optimal. The paper introduces a method new to economics, the Dubovitskii-Milyutin adjoint equation, to analyze the properties of the optimal control problem.     

A comparison of national saving rates in the UK, US and Italy

We develop the approach of Gokhale, Kotlikoff and Sabelhaus [1996. Understanding the postwar decline in US saving: A cohort analysis. Brookings Papers on Economic Activity 0, 315-390], based on the life-cycle model of savings, to decompose the differences in the national saving rates between the UK, US and Italy. Our work suggests that the US saving rate is lower principally because Americans on average retire later. In contrast, the Italian saving rate is higher predominantly because Italians are credit constrained, particularly when young. We also found that demography and the different tax and benefit systems are able to explain little of the cross-sectional differences in saving rates. The study accounts for the possible importance of inter-generational private transfers in determining saving rates.     

Bubble-free policy feedback rules

We consider a broad class of linear dynamic stochastic rational-expectations models made of a finite number N of structural equations for N+1 endogenous variables and to be closed by one policy feedback rule. We design, for any model of this class and any stationary VARMA solution of that model, a “bubble-free” policy feedback rule ensuring that this solution is not only the unique stationary solution of the closed model, but also its unique solution. We apply these results to locally linearisable models of the monetary transmission mechanism and obtain interest-rate rules that not only ensure the local determinacy of the targeted equilibrium in the neighbourhood of the steady state considered, but also prevent the economy from gradually leaving this neighbourhood.     

When old meets young? Germany's population ageing and the current account

In a three-region New Keynesian life-cycle model calibrated to Germany, the Euro area (without Germany) and the rest of the world, we analyze the impact of population ageing on net foreign asset and current account developments. Using unsynchronized demographic trends by taking those of Germany as given and assuming constant population everywhere else, we are able to generate German current account surpluses of up to 15% of GDP during the first half of this century. However, projected demographic trends from 2000 to 2080 in OECD countries (and China in an additional analysis) are much more synchronized. Feeding these into our model suggests that the average annual German current account surplus from 2000 to 2018 that should be attributed to ageing reduces to around 2.83% (1.23%) of GDP, with a maximum at 4.3% (2.7%) in 2006 (when taking into account China), turning negative around 2035.     

An integral equation representation for overlapping generations in continuous time

This paper develops a method for solving for the dynamic general equilibrium of a deterministic continuous time overlapping generations model with a finite-horizon life-cycle. The model has isoelastic preferences and allows for general assumptions about individual endowments and demographics. Solving for an equilibrium reduces to solving a nonlinear integral equation. In the special case of log utility, the integral equation is linear and global approximations to a solution are easily computed with linear algebra.     

A monetary theory with non-degenerate distributions

We construct and analyze a tractable search model of money with a non-degenerate distribution of money holdings. Analytical tractability comes from modeling decentralized exchange as directed search, which makes the monetary steady state block recursive. By adapting lattice-theoretic techniques, we characterize individuals? policy and value functions, and show that these functions satisfy the standard conditions of optimization. We prove that a unique monetary steady state exists and provide conditions under which the steady-state distribution of buyers over money balances is non-degenerate. Moreover, we analyze the properties of this distribution.     

Private money and bank runs

Abstract This paper studies bank runs in a model with private money. We show that allowing claims on demand deposits to circulate as a medium of exchange can help prevent bank runs. In our model, there exists a unique banking equilibrium where no one demands early withdrawals of real goods and agents in need of liquidity use private money to finance consumption. With private money, the unique equilibrium not only eliminates bank runs but also improves banking efficiency. The implications of our model are consistent with the evidence from the banking history of the United States.     

The choice between an annuity and a lump sum: Results from Swiss pension funds

This paper uses unique micro data from Swiss employer-based pension plans to study the annuitization decision at retirement. The administrative nature of our data, though limited with respect to individual background characteristics, allows us to analyze real choices over large retirement balances, rather than subjectively reported intentions to annuitize. We find a strong and robust impact of a utility-based measure of the annuity's value (computed within a life-cycle framework) on individual annuitization rates. Low accumulation of retirement assets is strongly associated with the choice of the lump sum, presumably due to the availability of means-tested social assistance. The sponsor's default option, in most cases the annuity, is also found to be highly influential in the decision to annuitize.     

A note on the life-cycle search and matching model with segmented labor markets

Recently, there has been renewed interest in labor search and matching models that incorporate a life-cycle structure by assuming finite horizons. Existing studies provide detailed analyses on the age dynamics of job creation and destruction, assuming that workers of all ages search for jobs in the same market. This paper examines a related environment that has drawn less attention, where the labor market is exogenously segmented by age. The paper finds sufficient conditions for the model to yield unambiguous predictions on the age profiles of key variables, and compares them with the corresponding conditions in models with a single market. The paper further examines the age profiles of these key variables in the efficient allocation. In particular, with no persistence in idiosyncratic match productivity, the efficient allocation is found to exhibit monotonic age profiles for the job finding and separation rates.     

Optimal versus realized policy rules in a regime-switching framework

In this paper we compare a deterministic model and a Markov switching model to analyze the behavior of the US economy and the Federal Reserve. We examine both optimal and empirical monetary policies for the US Federal Reserve between 1960 and 2008. We compare the optimal monetary policy to the actual interest rates and to the empirical reaction function. We also evaluate the sensitivity of the results to the preferences assigned to each objective. We find that there is no unique optimal solution that fits the Federal Reserve behavior over the entire period. The best fit to the actual interest rates is obtained by an optimal policy with preference switches following the rule: a high-volatility regime coincides with a priority on inflation alone while in a low-volatility regime there is equal policy priority on output stabilization and inflation.     

Expectations and optimal monetary policy: A stability problem revisited

A landmark result in the optimal monetary policy design literature is that fundamental-based interest rate rules invariably lead to rational expectations equilibria (REE) that are not stable under adaptive learning. In this paper, we make a novel information assumption that private agents cannot observe aggregate fundamental shocks, and use simple linear forecasting rules for learning. We find that with fundamental-based rules, there exist limited information equilibria that are stable under learning. Moreover, there are multiple equilibria. Learning can be used as a selection tool to identify a unique equilibrium.     

A life-cycle analysis of social security with housing

This paper incorporates two features of housing in a life-cycle analysis of social security: housing as a durable good and housing market frictions. We find that both housing quantities and homeownership rates respond strongly to eliminating social security. Accordingly, the aggregate impacts of this policy reform are significantly larger in an economy with explicit housing choices than in a standard life-cycle economy. Our analysis shows that the key mechanism behind these results is the substitution effects of a change in interest rates and, thus, the price of housing services on the choice of nondurable consumption versus housing services.     

Social security and unsecured debt

In this paper, we use a calibrated life-cycle model to explore quantitatively ways of reducing the burden of social security in a world populated by both optimizing and rule-of-thumb consumers. Social security contributions force young households with upward-sloping income profiles to save a sizeable portion of their income for retirement, when their optimal consumption plan would likely have them either saving little or borrowing. We first use household data to document that young households have accumulated social security contributions that are large relative to debt holdings. Then, using a calibrated life-cycle model, we show that both allowing households to use social security wealth to pay off their debt and exempting young households from social security contributions (but in both cases requiring higher contributions later) mitigate many of the inefficiencies of social security from the perspective of life-cycle financial planning. Specifically, in our preferred experiment, which exempts households whose heads are under 30 from making social security contributions, we find that certainty-equivalent consumption increases by 3.4% for optimizing households and by 3.3% for rule-of-thumb households.     

Innovation over the industry life-cycle: Evidence from EU manufacturing

Empirical research has revealed some regularities regarding the innovation that takes place over the industry life-cycle. First, innovation is high when an industry is young and low when the industry matures, and second, product innovation decreases with industry maturity, while process innovation increases. The implications of these regularities are profound, but evidence is to date largely case based and it is hard to generalize and draw policy conclusions. We use a flexible measure of maturity and a novel modeling approach to investigate innovation patterns for 21 European manufacturing industries. Our results strongly support both assertions and lend support to life-cycle based R&D-policy.     

Reassessing the effects of environmental taxation when pollution affects health over the life-cycle

We introduce the link between pollution, morbidity and productivity over the life-cycle in a two-period overlapping generations model. As the environmental tax improves the health-profile over the life-cycle, it influences saving, investment in health, labor supply and retirement. As a result, we identify effects of environmental taxation beyond the standard crowding-out and productivity effects captured by the past literature. We show that whether those effects are positive or negative for the economy crucially depends on the degree of substitutability between young and old labor. Our numerical examples suggest that that those new effects alleviate the negative effects of environmental taxation on output and decrease potential positive welfare effects.     

Optimal annuitization, uncertain survival probabilities, and maxmin preferences

We consider a life-cycle model with bequest motives, and assume that the individual does not know his/her survival probability and has maxmin utility preferences; we show that it is optimal not to annuitize but to purchase pure life insurance policies instead.     

How fragile are male labor supply function estimates?

We estimate male wage and nonwage income effects using linear specifications spanning three techniques (ordinary least squares, fixed effects, and random effects), two wage measures (reported hourly wages and average hourly earnings), and sample stratification by pay scheme (salaried versus hourly paid). Our regressions encompass the one-period static and perfect-foresight life-cycle models. The static model implies exogenous random person-specific effects, a negative nonwage income coefficient, and a positive labor supply substitution effect. The life-cycle model implies endogenous individual-specific effects, a positive wage coefficient, and a zero nonwage income coefficient. Neither the one-period static nor the perfect-foresight life-cycle models are implied by the data for salaried workers while the static model is consistent with the data for hourly paid workers if income taxes are ignored.     

Unique monetary equilibria with interest rate rules: An extension

In a recent paper, Adão et al. (2011), using a cash-in-advance framework, derive an interest rate rule that results in a unique monetary equilibrium. The resulting interest rate rule is forward looking and the interest rate responds positively to forecasts of future real activity and to forecasts of the future price level. This paper extends their approach to a transactions cost environment. The resulting interest rate rule has the added feature that, in line with previous studies, the nominal interest rate responds positively to forecasts of future inflation.     

Estimating the household consumption function in Saudi Arabia: an error correction approach

ABSTRACT

We estimate a micro-founded life-cycle consumption model for Saudi Arabia over the period 1970–2017 using error correction model procedures. Dynamic adjustments are significant, and both income and wealth are found to have significant effects, with a long-run marginal propensity to consume out of the income of 0.95 and out of the wealth of 0.06. The sensitivity of consumption to income and wealth, as well as the estimated short-term effects of price and real interest rate, are consistent with the rapidly growing Saudi economy. By capturing the key determinants of the life-cycle model, our approach is useful for the design of macroeconomic policy. We estimate the impact of the recent VAT reform.