Longevity and Lifetime Labor Supply: Evidence and Implications

Conventional wisdom suggests that increased life expectancy had a key role in causing a rise in investment in human capital. I incorporate the retirement decision into a version of Ben‐Porath's (1967) model and find that a necessary condition for this causal relationship to hold is that increased life expectancy will also increase lifetime labor supply. I then show that this condition does not hold for American men born between 1840 and 1970 and for the American population born between 1890 and 1970. The data suggest similar patterns in Western Europe. I end by discussing the implications of my findings for the debate on the fundamental causes of long‐run growth.     

THE QUANTITATIVE ROLE OF CHILD CARE FOR FEMALE LABOR FORCE PARTICIPATION AND FERTILITY

I document that the labor force participation rate of West German mothers with children aged zero to two exceeds the corresponding child‐care enrollment rate, while the opposite is true for mothers whose children are older than two but below the mandatory schooling age. These facts also hold for a cross‐section of E.U. countries. I develop a life‐cycle model that explicitly accounts for this age‐dependent relationship by including various types of nonpaid and paid child care. I calibrate this model to data for West Germany and use the calibrated model for policy analysis. Increasing the supply of subsidized child care for children aged zero to two generates an increase in the maternal labor force participation rate consistent with empirical evidence from other settings; however, this increase is too small to conclude that the lack of subsidized child care accounts for the low labor force participation rate of mothers with children aged zero to two. The response along the intensive margin suggests that a large fraction of part‐time working mothers would work full‐time if they had greater access to subsidized child care. Finally, making subsidized child care available to more women does not achieve one of the commonly stated goals of such reforms, namely to increase the fertility rate.     

Estimating the Return to Schooling: Progress on Some Persistent Econometric Problems

This paper reviews a set of recent studies that have attempted to measure the causal effect of education on labor market earnings by using institutional features of the supply side of the education system as exogenous determinants of schooling outcomes. A simple theoretical model that highlights the role of comparative advantage in the optimal schooling decision is presented and used to motivate an extended discussion of econometric issues, including the properties of ordinary least squares and instrumental variables estimators. A review of studies that have used compulsory schooling laws, differences in the accessibility of schools, and similar features as instrumental variables for completed education, reveals that the resulting estimates of the return to schooling are typically as big or bigger than the corresponding ordinary least squares estimates. One interpretation of this finding is that marginal returns to education among the low‐education subgroups typically affected by supply‐side innovations tend to be relatively high, reflecting their high marginal costs of schooling, rather than low ability that limits their return to education.     

Lifetime Buy Decisions with Multiple Obsolete Parts

Life‐cycle mismatch occurs when the life cycles of parts end before the life cycles of the products in which those parts are used. Lifetime buys are one tactic for mitigating the effect of part obsolescence, where a quantity of parts is purchased for the remaining life of a product. We extend prior work that determines optimal lifetime buy quantities for one product with one obsolete part by providing an analytic solution and two simple heuristic policies for the optimal lifetime buy quantities when many parts become obsolete over a product's life cycle. We determine which of our two heuristics is most accurate for different product life cycles, which yields a metaheuristic with increased accuracy. That analysis also reveals critical perspectives in making lifetime buy decisions with nonstationary life‐cycle demand patterns.     

Car Occupant Life Expectancy: Car Mass and Seat Belt Effects

Average human life expectancies for the U.S. resident population are calculated using tabulated population and survival rate data. These life expectancies are recalculated assuming elimination of various types of motor vehicle fatalities using Fatal Accident Reporting System (FARS) data. The differences between the original and recalculated values provide estimates of life expectancy reductions due to the motor vehicle fatalities. These estimates are combined with prior work relating the likelihood of an occupant fatality to car mass, so that reductions in life expectancy are determined as a function of car mass. The estimates of life expectancy reductions are also used to determine the effect of seat belt use on life expectancy. The estimates, which are based on data for 1978, assume that survival rates remain unchanged. Estimates of the changes in life expectancy associated with switching from a large (1800 kg) car to a small (900 kg) car, and switching from not using to using a seat belt are presented as functions of the age at which an individual makes the switch.     

Educational Inequality

Abstract. This paper develops a theoretical model of the inequality in wages and salaries associated with differences in years of schooling (educational inequality, for short). Our model assumes that in the long run individual decisions to become more educated equalize the lifetime earnings of more educated workers and comparable less educated workers. Given this assumption, our model implies that innovations that increase the relative demand for more educated labor, and which cause short‐run increases in educational inequality, in the long run induce offsetting increases in the relative supply of more educated labor. But our model also has the novel implication that innovations that increase differences between the wages and salaries received by workers with the same years of education who are more or less able (ability premiums, for short) cause a smaller fraction of workers to choose to become more educated. Consequently, innovations that increase ability premiums in the long run also cause educational inequality to be larger than otherwise. In applying our theory to recent changes in educational inequality in the USA, we suggest that, to the extent that innovations that increase ability premiums are contributing to educational inequality, the increases in educational inequality during the 1980s and 1990s are unlikely to be reversed soon.     

(Un)equal Educational Opportunities and the Labor Market: A Theoretical Analysis

This paper intends to study the effects of public school quality offer on the labor market performance. With this objective in mind, we build a matching model for the labor market in two sectors: schooled and non‐schooled. The skilled segment of the economy is endogenous and composed of a continuum of workers who differ in the quality of the school attended. We show that there is a trade‐off between the quantity and the quality of education and that a reduction in schooling costs increases school enrollment rates. However, it adversely reduces the job creation dynamics in the skilled sector, due to the Composition Effect. We also verify that a first order improvement in school quality distribution may generate an increase in the schooling rate and a greater job vacancy creation in the skilled sector with no negative effects on the unskilled sector.     

Addressing Supply–Demand Imbalance: Designing Efficient Remanufacturing Strategies

The management of remanufacturing inventory system is often challenged by mismatched supply (i.e., returned units, called cores) and demand. Typically, the demand for remanufactured units is high and exceeds the supply early in a product's lifetime, and drops below the supply late in the lifetime. This supply–demand imbalance motivates us to study a switching strategy to facilitate the decision‐making process. This strategy deploys a push mode at the early stage of a product's lifetime, which remanufactures scarce cores to stock to responsively satisfy the high demand, and switches to a pull mode as the product approaches obsolescence to accurately match the low demand with supply. In addition, the strategy further simplifies the decision‐making process by ignoring the impact of leftover cores at the end of each decision period. We show that the optimal policy of the switching strategy possesses a simple, multi‐dimensional base‐stock structure, which aims to remanufacture units from the i best‐quality categories up to the ith state‐independent base‐stock level. An extensive numerical study shows that the switching strategy delivers close‐to‐optimal and robust performance: the strategy only incurs an average profit loss of 1.21% and a maximum of 2.27%, compared with the optimal one. The numerical study also shows when a pure push or pull strategy, a special case of the switching strategy, delivers good performance. The study offers the managerial insight that firms can use simple, easy‐to‐implement strategies to efficiently manage the remanufacturing inventory system.     

THE PRIVATE AND FISCAL RETURNS TO SCHOOLING IN THE EUROPEAN UNION

We present estimates of the private and fiscal returns to schooling in 14 European Union countries. Estimates of the private returns to post‐compulsory formal education take into account the effects of schooling on wages and employment probabilities and allow for academic failure rates, the direct and opportunity costs of education, and the impact of personal taxes, social security contributions, and unemployment and pension benefits on lifetime earnings. Estimates of fiscal returns capture the long‐term effects of a marginal increase in average educational attainment on public finances under conditions that approximate general equilibrium. (JEL: I20, J31, H60).     

Minimum Wage Effects on Labor Market Outcomes under Search,Matching, and Endogenous Contact Rates

Building upon a continuous‐time model of search with Nash bargaining in a stationary environment, we analyze the effect of changes in minimum wages on labor market outcomes and welfare. Although minimum wage increases may or may not lead to increases in unemployment in our model, they can be welfare‐improving to labor market participants on both the supply and demand sides of the labor market. We discuss identification of the model using Current Population Survey data on accepted wages and unemployment durations, and show that by incorporating a limited amount of information from the demand side of the market it is possible to obtain credible and precise estimates of all primitive parameters. We show that the optimal minimum wage in 1996 depends critically on whether or not contact rates can be considered to be exogenous and we note that the limited variation in minimum wages makes testing this assumption problematic.     

Tax and Education Policy in a Heterogeneous‐Agent Economy: What Levels of Redistribution Maximize Growth and Efficiency?

This paper studies the effects of progressive income taxes and education finance in a dynamic heterogeneous‐agent economy. Such redistributive policies entail distortions to labor supply and savings, but also serve as partial substitutes for missing credit and insurance markets. The resulting tradeoffs for growth and efficiency are explored, both theoretically and quantitatively, in a model that yields complete analytical solutions. Progressive education finance always leads to higher income growth than taxes and transfers, but at the cost of lower insurance. Overall efficiency is assessed using a new measure that properly reflects aggregate resources and idiosyncratic risks but, unlike a standard social welfare function, does not reward equality per se. Simulations using empirical parameter estimates show that the efficiency costs and benefits of redistribution are generally of the same order of magnitude, resulting in plausible values for the optimal rates. Aggregate income and aggregate welfare provide only crude lower and upper bounds around the true efficiency tradeoff.     

整合工作、退休与一生收益决策的最优投资组合研究

将工作时间和退休年龄视为内生变量,用一个包含随机死亡概率和不确定劳动收入的标准化模型,探讨个人一生最优投资组合,拓展投资领域,使投资不仅包括购买股票和债券,而且还包括购买年金。研究表明,将劳动力供给看作内生变量不仅能提高老年人股票持有量,而且能极大提高年轻人工作努力程度,显著改善个人一生福利。此外,引入年金也将导致老年人提前退休和更多参与金融活动。最后,如果考虑取决于年龄的闲暇偏好,随着接近退休年龄,个人将减少工作时间和股票持有量。     

To What Extent Are Labor‐Saving Technologies Improving Efficiency in the Use of Human Resources? Evidence from the Banking Industry

With special reference to the banking industry, the objective of this study is to address managerial concerns over the impact of labor‐saving technologies on efficiency in the use of human resources. A bank is viewed as a collection of human, technology, and capital resources. Labor‐saving technologies are represented by two categories of technology resources—information technologies and patented in‐house process innovations. The estimation of a stochastic frontier manpower‐requirement function shows that, whereas information technology resources have a direct impact on efficiency in the use of human resources, in‐house process innovations have an indirect impact through spillovers. The reduction in labor costs resulting from a more efficient use of human resources is more than enough to cover the required increase in information technology expenditures. This cost‐reducing impact is stronger for firms currently employing a lower level of information technologies. The empirical findings also suggest a complementary relationship between information technologies and spillovers of in‐house process innovations. The empirical framework proposed in this study can help decision makers determine the optimal input mix of technology and human resources.     

SOCIAL INTERACTIONS IN LABOR SUPPLY

Our research examines the effect of interdependence on estimation and interpretation of earnings/labor supply equations. We consider the cases of (1) a positive spillover from others' labor supplied and (2) a need for conformity with others' labor supplied. Qualitative and quantitative comparative statics results with a Stone‐Geary utility function demonstrate how spillover effects increase labor supply uniformly. Alternatively, conformity effects move labor supplied toward the mean of the reference group so that, in the limit, labor supply becomes perfectly inelastic at the reference group average. When there are unmodeled exogenous social interactions, conventional wage elasticities are still relatively well estimated, although structural parameters may not be. Omitting endogenous social interactions may seriously misrepresent the labor supply effects of policy, however. (JEL: D11, J22, Z13)     

Segmentation,Mobility and the Spatial Distribution of Activities

Abstract. The paper discusses the relationship between labor economics' segmentation theory and the polarization theories of regional economics. It is argued that labor market segmentation and regional disparities are fundamentally related and that one is both cause and consequence of the other. The argument is developed around the locational requirements of various functions of entreprises on the one hand and worker's schooling and migration decisions on the other. As can be shown, interregional labor mobility that is usually considered to be an important factor in equilibrating regional disparities enforces the interregional differentiation in a model allowing for a segmented labor market. The paper closes with reference of a few fundamental hypotheses that can be derived from the model and cites empirical evidence supporting this view.     

Female Labor Supply,Human Capital,and Welfare Reform

We estimate a dynamic model of employment, human capital accumulation—including education, and savings for women in the United Kingdom, exploiting tax and benefit reforms, and use it to analyze the effects of welfare policy. We find substantial elasticities for labor supply and particularly for lone mothers. Returns to experience, which are important in determining the longer‐term effects of policy, increase with education, but experience mainly accumulates when in full‐time employment. Tax credits are welfare improving in the U.K., increase lone‐mother labor supply and marginally reduce educational attainment, but the employment effects do not extend beyond the period of eligibility. Marginal increases in tax credits improve welfare more than equally costly increases in income support or tax cuts.     

COMPETITIVE MARKETS WITH ENDOGENOUS HEALTH RISKS

We study an economy where agents' productivity and labor endowment depend on their health status, and indivisible occupational choices affect individual health distributions. We show that Pareto efficiency requires cross‐transfers across occupations. Moreover, workers with relatively less safe jobs must get positive transfers whenever labor supply is not very reactive to wages, a condition in line with the findings of a large empirical literature. In these instances, compensating wage differentials equalizing the utilities of ex‐ante identical workers in different jobs undermine ex‐ante efficiency. Moreover, competitive equilibria where only assets with deterministic payoffs are traded are not first‐best. Finally, we show that simple transfer schemes, implemented through linear subsidies to health insurance, enhance efficiency.     

Capital‐skill Complementarity and Inequality: A Macroeconomic Analysis

The supply and price of skilled labor relative to unskilled labor have changed dramatically over the postwar period. The relative quantity of skilled labor has increased substantially, and the skill premium, which is the wage of skilled labor relative to that of unskilled labor, has grown significantly since 1980. Many studies have found that accounting for the increase in the skill premium on the basis of observable variables is difficult and have concluded implicitly that latent skill‐biased technological change must be the main factor responsible. This paper examines that view systematically. We develop a framework that provides a simple, explicit economic mechanism for understanding skill‐biased technological change in terms of observable variables, and we use the framework to evaluate the fraction of variation in the skill premium that can be accounted for by changes in observed factor quantities. We find that with capital‐skill complementarity, changes in observed inputs alone can account for most of the variations in the skill premium over the last 30 years.     

Dynamic Female Labor Supply

The increase in female employment and participation rates is one of the most dramatic changes to have taken place in the economy during the last century. However, while the employment rate of married women more than doubled during the last 50 years, that of unmarried women remained almost constant. To empirically analyze these trends, we estimate a female dynamic labor supply model using an extended version of Eckstein and Wolpin (1989) to compare the various explanations in the literature for the observed trends. This dynamic model provides a much better fit to the life‐cycle employment pattern than a static version of the model and a standard static reduced form model (Heckman (1979)). The main finding using the dynamic model is that the rise in education levels accounts for about 33 percent of the increase in female employment, and the rise in wages and narrowing of the gender wage gap account for another 20 percent, while about 40 percent remains unexplained by observed household characteristics. We show that this unexplained portion can be empirically attributed to cohort‐specific changes in preferences or the costs of child‐rearing and household maintenance. Finally, the decline in fertility and the increase in divorce rates account for only a small share of the increase in female employment rates.     

Approximations for Estimating Change in Life Expectancy Attributable to Air Pollution in Relation to Multiple Causes of Death Using a Cause Modified Life Table

There is considerable debate as to the most appropriate metric for characterizing the mortality impacts of air pollution. Life expectancy has been advocated as an informative measure. Although the life‐table calculus is relatively straightforward, it becomes increasingly cumbersome when repeated over large numbers of geographic areas and for multiple causes of death. Two simplifying assumptions were evaluated: linearity of the relation between excess rate ratio and change in life expectancy, and additivity of cause‐specific life‐table calculations. We employed excess rate ratios linking PM_2.5 and mortality from cerebrovascular disease, chronic obstructive pulmonary disease, ischemic heart disease, and lung cancer derived from a meta‐analysis of worldwide cohort studies. As a sensitivity analysis, we employed an integrated exposure response function based on the observed risk of PM_2.5 over a wide range of concentrations from ambient exposure, indoor exposure, second‐hand smoke, and personal smoking. Impacts were estimated in relation to a change in PM_2.5 from 19.5 μg/m³ estimated for Toronto to an estimated natural background concentration of 1.8 μg/m³. Estimated changes in life expectancy varied linearly with excess rate ratios, but at higher values the relationship was more accurately represented as a nonlinear function. Changes in life expectancy attributed to specific causes of death were additive with maximum error of 10%. Results were sensitive to assumptions about the air pollution concentration below which effects on mortality were not quantified. We have demonstrated valid approximations comprising expression of change in life expectancy as a function of excess mortality and summation across multiple causes of death.