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on Labour Economics |
| By: | Jörg Lingens; Klaus Wälde |
| Abstract: | We investigate how continental European unemployment can be reduced without reducing unemployment benefits and without reducing the net income of low-wage earners. Lower unemployment replacement rates reduce unemployment, the net wage and unemployment benefits. A lower tax on labour increases net wages and - for certain benefit-systems - unemployment benefits as well. Combining these two policies allows to reduce unemployment in countries with “net-Bismarck” and Beveridge systems without reducing net income of workers or of the unemployed. Such a policy becomes self-financing under realistic parameter constellations when taxes are reduced only for low-income workers. |
| Keywords: | inequality, unemployment, taxation, policy reform |
| JEL: | E60 H23 J38 J51 |
| Date: | 2006 |
| URL: | http://d.repec.org/n?u=RePEc:ces:ceswps:_1807&r=lab |
| By: | Giovanni L. Violante; Per Krusell; Andreas Hornstein |
| Abstract: | Standard search and matching models of equilibrium unemployment, once properly calibrated, can generate only a small amount of frictional wage dispersion, i.e., wage differerentials among ex-ante similar workers induced purely by search frictions. We derive this result for a specific measure of wage dispersion - the ratio between the average wage and the lowest (reservation) wage paid. We show that in a large class of search and matching models this statistic (the "mean-min ratio") can be obtained in closed form as a function of observable variables (i.e., interest rate, value of leisure, and statistics of labor market turnover). Looking at various independent data sources suggests that, empirically, residual wage dispersion (i.e., inequality among observationally similar workers) exceeds the model's prediction by a factor of 20. We discuss three extensions of the model (risk aversion, volatile wages during employment, and on-the-job search) and find that, in their simplest version, they can improve its performance, but only modestly. We conclude that either frictions account for a tiny fraction of residual wage dispersion, or the standard model needs to be augmented to confront the data. |
| Date: | 2006 |
| URL: | http://d.repec.org/n?u=RePEc:fip:fedrwp:06-07&r=lab |
| By: | Budria, Santiago; Telhado-Pereira, Pedro |
| Abstract: | This paper explores the connection between education and wage inequality in nine European countries. We exploit the quantile regression technique to calculate returns to lower secondary, upper secondary and tertiary education at different points of the wage distribution. We find that in most countries returns to tertiary education are highly increasing when moving from the lower to the upper quantiles. This finding suggests that an educational expansion towards tertiary education is expected to increase overall within-groups inequality in Europe. In turn, returns to secondary education are quite homogeneous across quantiles, suggesting that an educational expansion towards secondary education is expected to have only a limited impact on within-groups dispersion. Using data from the last decades, we describe changes in the conditional wage distribution of the surveyed countries. A common feature in Europe is that over the last years wage dispersion increased within the high educated. |
| Keywords: | Returns to education; Quantile regression; Wage inequality |
| JEL: | C29 D31 |
| Date: | 2005 |
| URL: | http://d.repec.org/n?u=RePEc:pra:mprapa:91&r=lab |
| By: | Giovanni L. Violante; Per Krusell; Andreas Hornstein |
| Abstract: | In this Technical Appendix to Hornstein, Krusell, and Violante (2006) (HKV, 2006, hereafter) we provide a detailed characterization of the search model with (1) wage shocks during employment and (2) on-the-job search outlined in Sections 6 and 7 of that paper, and we derive all of the results that are only stated in HKV (2006). In particular, we derive the expressions for our preferred measure of frictional wage inequality: the ratio of average wages to the reservation wage, or, the 'mean-min' wage ratio. |
| Date: | 2006 |
| URL: | http://d.repec.org/n?u=RePEc:fip:fedrwp:06-08&r=lab |
| By: | Budria, Santiago |
| Abstract: | International research has shown that schooling enhances within-groups wage dispersion. This assessment is typically based on private sector data and, up to date, the inequality implications of schooling have not been documented for the public sector. This paper uses recent data from eight European countries to explicitly take into account differences between the private and public sectors. Using quantile regression, the paper describes the effects of schooling on the location and shape of the conditional wage distribution in each sector. While the average impact of schooling on wages is similar across sectors, the impact of schooling on within-groups dispersion is found to be substantially larger in the private sector than in the public sector. This finding warns that the effects of the European educational expansion on overall within-groups dispersion may be lower than previously thought. |
| Keywords: | Returns to schooling; Quantile regression; Within-groups wage inequality |
| JEL: | I21 D31 |
| Date: | 2006–09 |
| URL: | http://d.repec.org/n?u=RePEc:pra:mprapa:90&r=lab |
| By: | Antonio Dias da Silva (Vrije Universiteit Amsterdam); Bas van der Klaauw (Vrije Universiteit Amsterdam) |
| Abstract: | We focus on the dynamic relation between wage increases, promotions and job changes. We relate our empirical analyses to the theoretical model of Gibbons and Waldman (1999). In the empirical analyses we use the Portuguese matched employer-employee data Quadros de Pessoal. We conclude from finding significant serial correlation in wage increases and promotion rates that employer learning about the worker's ability might be important. Furthermore, we find that the Portuguese labor market is not competitive. Finally, we argue that employer-reported promotion relate to a large extent to wage increases rather than changes in job tasks and complexity. |
| Keywords: | learning; competition; dynamic panel data models; matched employer-employee data |
| JEL: | M5 J6 L2 |
| URL: | http://d.repec.org/n?u=RePEc:dgr:uvatin:20060084&r=lab |
| By: | Andy Snell; Jonathan Thomas |
| Abstract: | This paper analyses a model in which firms cannot pay discriminate based on year of entry to a firm, and develops an equilibrium model of wage dynamics and unemployment. The model is developed under the assumption of worker mobility, so that workers can costlessly quit jobs at any time. Firms on the other hand are committed to contracts. Thus the model is related to Beaudry and DiNardo (1991). We solve for the dynamics of wages and unemployment, and show that real wages do not necessarily clear the labor market. Using sectoral productivity data from the post-war US economy, we assess the ability of the model to match actual unemployment and wage series. We also show that equal treatment follows in our model from the assumption of at-will employment contracting. |
| JEL: | E32 J41 |
| Date: | 2006–09 |
| URL: | http://d.repec.org/n?u=RePEc:san:cdmacp:0603&r=lab |
| By: | Juanna Schrøter Joensen; Helena Skyt Nielsen (School of Economics and Management, University of Aarhus, Denmark) |
| Abstract: | Outsourcing of jobs to low-wage countries has increased the focus on the accumulation of skills - such as Math skills - in high-wage countries. In this paper, we exploit a high school pilot scheme to identify the causal effect of advanced high school Math on labor market outcomes. The pilot scheme reduced the costs of choosing advanced Math because it allowed for at more flexible combination of Math with other courses. We find clear evidence of a causal relationship between Math and earnings for the students who are induced to choose Math after being exposed to the pilot scheme. The effect partly stems from the fact that these students end up with higher education. |
| Keywords: | Math, High School Curriculum, Instrumental Variable, Local Average Treatment Effect. |
| JEL: | I20 J24 |
| Date: | 2006–10–03 |
| URL: | http://d.repec.org/n?u=RePEc:aah:aarhec:2006-11&r=lab |
| By: | Richard B. Freeman |
| Abstract: | This paper assesses the claim the the US faces an impending labor shortage due to the impending retirement of baby boomers and slow growth of the US work force, and that the country should orient labor market and educational policies to alleviate this prospective shortage. I find that this analysis is flawed, by making growth of GDP the target of economic policy and by paying inadequate attention to the huge supply of qualified low wage workers in the global economy. My analysis shows that the projections of future demands for skills lack the reliability to guide policies on skill development, and that contrary to the assumption implicit in the shortage analyses, demographic changes have not historically been consistently associated with changes in labor market conditions. I argue that if there is to be a shortage, the country should allow the competitive market to raise labor compensation rather than to adopt policies to keep labor costs low. |
| Date: | 2006–09 |
| URL: | http://d.repec.org/n?u=RePEc:nbr:nberwo:12541&r=lab |
| By: | Woodcock, Simon |
| Abstract: | We present an empirical model of earnings that controls for observable and unobservable characteristics of workers (person effects), unmeasured characteristics of their employers (firm effects), and unmeasured characteristics of worker-firm matches (match effects). We interpret these as the returns to general human capital, firm-specific human capital, and match-specific human capital, respectively. We stress the importance of match effects because the returns to match-specific human capital will be incorrectly attributed to general and/or firm-specific human capital when match effects are omitted, and because general and specific human capital have very different implications for the economic cost of job destruction. We find that slightly more than half of observed variation in log earnings is attributable to general human capital, 22 percent is attributable to firm-specific human capital, and 16 percent to match-specific human capital. Specifications that omit match effects over-estimate the returns to experience by as much as 50 percent, over-estimate the returns to a college education by as much as 8 percent, attribute too much variation to person effects, and too little to firm effects. Our results suggest that considerable earnings variation previously attributed to general human capital -- both observed and unobserved -- is in fact attributable to workers sorting into higher-paying firms and better worker-firm matches. |
| Keywords: | human capital; fixed effects; mixed effects; person and firm effects; linked employer-employee data |
| JEL: | C23 J24 |
| Date: | 2006–09 |
| URL: | http://d.repec.org/n?u=RePEc:pra:mprapa:154&r=lab |
| By: | Courtney C. Coile; Phillip B. Levine |
| Abstract: | This paper examines how unemployment affects retirement and whether the Unemployment Insurance (UI) system and Social Security (SS) system affect how older workers respond to labor market shocks. To do so, we use pooled cross-sectional data from the March Current Population Survey (CPS) as well as March CPS files matched between one year and the next and longitudinal data from the Health and Retirement Survey (HRS). We find that downturns in the labor market increase retirement transitions. The magnitude of this effect is comparable to that associated with moderate changes in financial incentives to retire and to the threat of a health shock to which older workers are exposed. Interestingly, retirements only increase in response to an economic downturn once workers become SS-eligible, suggesting that retirement benefits may help alleviate the income loss associated with a weak labor market. We also estimate the impact of UI generosity on retirement and find little consistent evidence of an effect. This suggests that in some ways SS may serve as a more effective form of unemployment insurance for older workers than UI. |
| JEL: | H55 J26 J64 J65 |
| Date: | 2006–10 |
| URL: | http://d.repec.org/n?u=RePEc:nbr:nberwo:12559&r=lab |
| By: | Kevin E. Cahill (Analysis Group, Inc.); Michael D. Giandrea (U.S. Bureau of Labor Statistics); Joseph F. Quinn (Boston College) |
| Abstract: | Aggregate data reveal a sizable increase in labor force participation rates since 2000 among workers on the cusp of retirement, reverting back to levels for older men not seen since the 1970s. These aggregate numbers are useful in that they document overall trends, but they lack the ability to identify the reasons behind workers’ decisions. The Health and Retirement Study (HRS) spans the last dozen years from 1992 to 2004, includes two cohorts of retirees, and provides micro-level data regarding these recent trends. Moreover, the HRS contains information on older Americans and the types of jobs they are taking (full-time versus part-time, self-employed versus wage-and-salary, low-paying versus high-paying, blue collar versus white collar, etc.). This study capitalizes on the richness of the HRS data and explores labor force determinants and outcomes of older Americans, with an emphasis on retirees' choices in recent years. We present a cross-sectional and longitudinal description of the financial, health, and employment situation of older Americans. We then explore retirement determinants using a multinomial approach to model gradual retirement and a two-step approach to model the work-leisure and hours intensity decisions of older workers. Evidence suggests that the majority of older Americans retire gradually, in stages, and that younger retirees continue to respond to financial incentives just as their predecessors did. In addition, recent macro-level changes appear to have blurred the distinction between younger and middle-aged retirees. |
| Keywords: | Economics of Aging, Partial Retirement, Gradual Retirement |
| JEL: | J26 J14 J32 H55 |
| Date: | 2006–10 |
| URL: | http://d.repec.org/n?u=RePEc:bls:wpaper:ec060120&r=lab |
| By: | Antonis Adam; Thomas Moutos |
| Abstract: | In this paper we construct a political economy model in which minimum wages are determined according to the wishes of the median voter. Using the minimum wage scheme as the status quo, we show that the replacement of minimum wages by wage subsidies guaranteeing the same (pre-tax) level of income (achieved by the government supplementing the wage income of workers by a subsidy equal to the difference between the competitive wage rate and the minimum wage rate), is not likely to receive political support unless it is supplemented by increased taxation of profits (after-tax profits are also likely to increase). Moreover, we show that the likelihood of implementation of wage subsidies is undermined by the existence of a heterogeneous labour force. |
| Keywords: | minimum wages, wage subsidies, median voter, political economy |
| JEL: | D72 E24 E62 |
| Date: | 2006 |
| URL: | http://d.repec.org/n?u=RePEc:ces:ceswps:_1810&r=lab |
| By: | Shigeru Fujita; Garey Ramey |
| Abstract: | In this paper the authors study the cyclical behavior of job loss and hiring using CPS worker flow data, adjusted for margin error and time aggregation error. The band pass filter is used to isolate cyclical components. They consider both total worker flows and transition hazard rates within a unified framework. Our results provide overwhelming support for a "separation-driven" view of employment adjustment, whereby total job loss and hiring rise sharply during economic downturns, initiated by increases in the job loss hazard rate. Worker flows and transition hazard rates are highly volatile at business cycle frequencies. These patterns are especially strong among prime-age workers. For young workers, job loss and hiring adjust procyclically due to movements into and out of the labor force. |
| Keywords: | Employment |
| Date: | 2006 |
| URL: | http://d.repec.org/n?u=RePEc:fip:fedpwp:06-17&r=lab |
| By: | Paul Beaudry; Mark Doms; Ethan Lewis |
| Abstract: | This paper focuses on the bi-directional interaction between technology adoption and labor market conditions. We examine cross-city differences in PC adoption, relative wages, and changes in relative wages over the period 1980-2000 to evaluate whether the patterns conform to the predictions of a neoclassical model of endogenous technology adoption. Our approach melds the literature on the effect of the relative supply of skilled labor on technology adoption to the often distinct literature on how technological change influences the relative demand for skilled labor. Our results support the idea that differences in technology use across cities and its effects on wages reflect an equilibrium response to local factor supply conditions. The model and data suggest that cities initially endowed with relatively abundant and cheap skilled labor adopted PCs more aggressively than cities with relatively expensive skilled labor, causing returns to skill to increase most in cities that adopted PCs most intensively. Our findings indicate that neoclassical models of endogenous technology adoption can be very useful for understanding where technological change arises and how it affects markets. |
| Keywords: | Technological innovations ; Labor market |
| Date: | 2006 |
| URL: | http://d.repec.org/n?u=RePEc:fip:fedfwp:2006-24&r=lab |
| By: | Parantap Basu |
| Abstract: | Labour market friction is viewed as the Tobin’s Q of an employed worker as opposed to the position of the Beveridge curve. This Tobin’s Q is inversely proportional to the average quality of the match between employers and workers. Based on this measure, I find that the labour market friction behaves procyclically in the US, which is indicative of the fact that firms compromise on the quality of the skill match during an expansion. |
| Date: | 2006–09 |
| URL: | http://d.repec.org/n?u=RePEc:san:cdmacp:0601&r=lab |
| By: | Jim Malley; Hassan Molana |
| Abstract: | We construct a stylised model of the supply side with goods and labour market imperfections to show that an economy can rationally operate at an inefficient, or ‘low-effort’, state in which the relationship between output and unemployment is positive. We examine data from the G7 countries over 1960-2001 and find that only German data strongly favour a persistent negative relationship between the level of output and rate of unemployment. The consequence of this is that circumstances exist in which market imperfections could pose serious obstacles to the smooth working of expansionary and/or stabilization policies and a positive demand shock might have adverse effects on employment. |
| Keywords: | Efficiency wages, effort supply, Kalman filter, monopolistic competition, Okun’s law. |
| JEL: | E62 J41 H3 |
| Date: | 2006–09 |
| URL: | http://d.repec.org/n?u=RePEc:san:cdmacp:0607&r=lab |
| By: | Bargain O; Orsini K |
| Abstract: | Social assistance and inactivity traps have long been considered as one of the main causes of the poor employment performance of EU countries. The success of New Labour in the UK has triggered a growing interests in instruments capable of combining the promotion of responsibility and self-sufficiency with solidarity with less skilled workers. Making-work-pay (MWP) policies, consisting of transfers to households with low earning capacity, have quickly emerged as the most politically acceptable instruments in tax-benefit reforms of many Anglo Saxon countries. This paper explores the impact of introducing the British Working Families' Tax Credit in three EU countries with rather different labor market and welfare institutions: Finland, France and Germany. Simulating the reform reveals that, while first round effects on income distribution is considerable, the interaction of the new instrument with the structural characteristics of the economy and the population may lead to counterproductive second round effects (i.e. changes in economic behavior). The implementation of the reform, in this case, could only be justified if the social inclusion (i.e. transition into activity) of some specific household types (singles and single mothers) is valued more than a rise in the employment per se. |
| Keywords: | tax-benefit systems, in-work benefits, microsimulation, poverty |
| JEL: | H31 H53 I32 I38 |
| Date: | 2006–04 |
| URL: | http://d.repec.org/n?u=RePEc:ese:emodwp:em2/06&r=lab |
| By: | Marla Ripoll; Juan Carlos Cordoba |
| Date: | 2005–01 |
| URL: | http://d.repec.org/n?u=RePEc:pit:wpaper:246&r=lab |
| By: | Magdalena Muszynska (Max Planck Institute for Demographic Research, Rostock, Germany); Hill Kulu (Max Planck Institute for Demographic Research, Rostock, Germany) |
| Abstract: | A growing body of literature looks at the consequences of family migration from a gender perspective. The studies show that women’s economic well-being and employment suffer from family migration, which is usually stimulated by the career of the male earner in the family. This study extends current research on the subject by examining the effect of family migration on union dissolution. We use the event-history data of two retrospective surveys from Russia and apply hazard regression. The analysis shows that couples who move frequently over long distances have a significantly higher risk of union dissolution than couples who do not move or move only once. Our further analysis reveals that the risk of disruption for frequent movers is high when the migrant woman has a job. Frequent migrants had a high risk of union dissolution in the Soviet period but not so during the post-Soviet socio-economic transition. We argue that frequent moving increases union instability through a variety of mechanisms, the effect of which may vary across socio-economic contexts, however. |
| Keywords: | Russia, divorce, event history analysis, internal migration |
| JEL: | J1 Z0 |
| Date: | 2006–09 |
| URL: | http://d.repec.org/n?u=RePEc:dem:wpaper:wp-2006-032&r=lab |
| By: | Dani Rodrik |
| Abstract: | South Africa has undergone a remarkable transformation since its democratic transition in 1994, but economic growth and employment generation have been disappointing. Most worryingly, unemployment is currently among the highest in the world. While the proximate cause of high unemployment is that prevailing wages levels are too high, the deeper cause lies elsewhere, and is intimately connected to the inability of the South African to generate much growth momentum in the past decade. High unemployment and low growth are both ultimately the result of the shrinkage of the non-mineral tradable sector since the early 1990s. The weakness in particular of export-oriented manufacturing has deprived South Africa from growth opportunities as well as from job creation at the relatively low end of the skill distribution. Econometric analysis identifies the decline in the relative profitability of manufacturing in the 1990s as the most important contributor to the lack of vitality in that sector. |
| JEL: | O11 O14 |
| Date: | 2006–10 |
| URL: | http://d.repec.org/n?u=RePEc:nbr:nberwo:12565&r=lab |
| By: | Lokshin, Michael; Beegle, Kathleen |
| Abstract: | The authors estimate the economic losses related to the negative effect of smoking on wages in a context of a developing country. Using data from the 2005 Albania Living Standards Monitoring Survey, they jointly estimate a system of three equations: the smoking decision and two separate wage equations for smokers and nonsmokers. The results show that, after controlling for observed characteristics and taking into account unobserved heterogeneity in personal characteristics, smoking has a substantial negative impact on wages. On average smokers ' wages are 20 percent lower than the wages of similar nonsmokers, providing strong evidence for the potential policy relevance of tobacco control initiatives for developing countries. |
| Keywords: | Health Monitoring & Evaluation,Tobacco Use and Control,Alcohol and Substance Abuse,Adolescent Health,Disease Control & Prevention |
| Date: | 2006–10–01 |
| URL: | http://d.repec.org/n?u=RePEc:wbk:wbrwps:4018&r=lab |
| By: | James Giesecke; G.A.Meagher |
| Abstract: | The paper uses MONASH, a dynamic computable general equilibrium model, to investigate the impact on the Australian economy of a 50 per cent increase in the skilled migrant intake over the period 2005-2025. The primary purpose of the modelling it to identify how the labour market might absorb an increase in the number of skilled visa entrants. To that end, the modelling recognises labour supply by 67 types of skill (defined as an education field classified by an education level) and 81 occupations. We find that, even with the increase in immigration heavily weighted towards skilled visa entrants, the main effect of the policy is to increase the scale of the economy. The main compositional effects are to shift economic activity towards the construction sector and sectors supplying material inputs to construction activity, raise the relative wages of workers that supply labour used intensively in construction and related sectors, reduce the relative wages of skilled labour, and increase returns to capital relative to labour. |
| Keywords: | CGE modelling, skilled immigration |
| JEL: | C68 J31 J61 |
| Date: | 2006–05 |
| URL: | http://d.repec.org/n?u=RePEc:cop:wpaper:g-157&r=lab |
| By: | Dennis Dittrich; Martin Kocher |
| Abstract: | We present an experimental test of a shirking model where monitoring intensity is endogenous and effort a continuous variable. Wage level, monitoring intensity and consequently the desired enforceable effort level are jointly determined by the maximization problem of the firm. As a result, monitoring and pay should be complements. In our experiment, between and within treatment variation is qualitatively in line with the normative predictions of the model under selfishness assumptions. Yet, we also find evidence for reciprocal behavior. The data analysis shows, however, that it does not pay for the employer to rely on the reciprocity of employees. |
| Keywords: | incentive contracts, supervision, efficiency wages, experiment, incomplete contracts, reciprocity |
| JEL: | C91 J31 J41 |
| Date: | 2006–10 |
| URL: | http://d.repec.org/n?u=RePEc:esi:discus:2006-23&r=lab |
| By: | McKenzie, David J. |
| Abstract: | The paper uses individual level census and household survey data to present a rich profile of the young developing migrants around the world. Youth are found to comprise a large share of all migrants, particularly in migration to other developing countries, with the probability of migration peaking in the late teens or early twenties. The paper examines in detail the age and gender composition of migrants, whether young migrants move alone or with a parent or spouse, their participation in schooling and work in the destination country, the types of jobs they do, and the age of return migration. The results suggest a high degree of commonality in the youth migrant experience across a number of destination countries. In particular, developing country youth tend to work in similar occupations all around the world, and are more concentrated in these occupations than older migrants or native youth. Nevertheless, there is also considerable heterogeneity among youth migrants: 29 percent of 18 to 24 year olds are attending school in their destination country, but another 29 percent are not working or in school. This illustrates both the potential of migration for building human capital, and the fear that lack of integration prevents it from being used. |
| Keywords: | Population Policies,Youth and Governance,Adolescent Health,Gender and Development,Population & Development |
| Date: | 2006–10–01 |
| URL: | http://d.repec.org/n?u=RePEc:wbk:wbrwps:4021&r=lab |
| By: | Michal Myck; Howard Reed |
| Abstract: | We present a method for taking advantage of labour market transitions to identify effects of financial incentives on employment decisions. The framework we use is very flexible and by imposing few theoretical assumptions allows extending the modelled sample relative to struc-tural models. We take advantage of this flexibility to include disabled people in the model and to analyse behaviour of disabled and non-disabled people jointly. A great deal of attention is paid to appropriate modelling of financial incentives on the labour market. This in the case of disabled people turns out to be an extremely complex process but one which in the end turns out well worth the effort. The model is used to compare reactions on the labour market to marginal changes in financial incentives and also to model one of the most important reforms of the UK Labour government, the introduction of the Working Families' Tax Credit. The methodology relies on matching transitions and incomes data between cross-sectional and panel surveys, and could be used in other countries where detailed reliable income data are not collected in a panel format. |
| Date: | 2006 |
| URL: | http://d.repec.org/n?u=RePEc:diw:diwwpp:dp625&r=lab |
| By: | Michael Lechner; Conny Wunsch |
| Abstract: | We estimate short, medium, and long-run individual labor market effects of training programs for unemployed by following program participation on a monthly basis over a tenyear period. Since analyzing the effectiveness of training over such a long period is impossible with experimental data, we use an administrative database compiled for evaluating German training programs. Based on matching estimation adapted to the various issues that arise in this particular context, we find a clear positive relation between the effectiveness of the programs and the unemployment rate over time. |
| Keywords: | Active labor market policy, long-run effects, matching estimation, causal effects, program evaluation, panel data |
| JEL: | J |
| Date: | 2006–10 |
| URL: | http://d.repec.org/n?u=RePEc:usg:dp2006:2006-23&r=lab |