geographic mobility race and wage differentials abstract this paper analyzes the relationship between geographic mobility and earnings we present an equilibrium search model that yields differences between the reservation wages of mobile and immobile workers the expected wages of mobile workers exceed those of immobile workers due to partial sorting across high and low paying firms an extension to visibly distinct groups with different immobile proportions yields statistical discrimination against immobile group members using combined displaced workers files we find that mobility positively affects earnings and partially explains racial and ethnic earnings differentials to test for statistical discrimination we estimate separate earnings functions for union and nonunion workers

the impact of economic growth on co2 emissions in azerbaijan abstract this paper investigates the relationship between the economic growth and co2 emissions in azerbaijan a cointegration analysis is conducted over the period 1992 2013 for getting more robust results johansen ardlbt dols fmols and ccr methods are employed to explore cointegration and estimate long run coefficients we use cubic quadratic and linear specifications and conclude that the last one is an adequate representation for the impact of the economic growth on co2 emissions in azerbaijan the results from the different cointegration methods are consistent with each other and show that the economic growth has a positive and statistically significant impact on the emissions in the long run implying that the ekc hypothesis does not hold for azerbaijan the income elasticity of co2 emissions using different methods is found to be between 0 7 and 0 8 moreover we find that any short run imbalance can be adjusted towards the long run equilibrium path within less than one year the paper concludes that measures to increase energy efficiency carbon pricing instruments in production and international domestic trade activities and nationwide social awareness programs to instruct about the negative consequences of pollution can be considered as relevant environmental policies aimed at reducing carbon emissions

nonunion wage rates and the threat of unionization i investigate how the threat of union organization affects the wage paid to nonunion workers i start by outlining the standard model of wage determination by a nonunion employer when faced with the threat of union organization the model suggests that the nonunion wage will be directly related and the union wage gap will be inversely related to the threat i use repeated cross section data from the cps from 1977 2002 to develop a measure of the threat as the predicted probability of union membership i use this measure to estimate earnings functions that use several sources of variation in the likelihood of union membership to identify the threat effect in a manner that reduces the likelihood of omitted variable bias finally i investigate two cases where there has arguably been a change in the likelihood of union organization that is not correlated with changes in the demand for labor these include the wage changes surrounding the introduction of rightto work rtw laws in two states during the period studied and wage changes surrounding deregulation of key industries in the late 1970s and early 1980s the results are mixed the preferred estimates from the analysis using predicted probability of unionization as the threat measure imply very little relationship between either nonunion wages or the union wage gap and the threat the estimates that rely on the introduction of rtw laws show a significant relationship between nonunion wages and the introduction of rtw laws in one of the two states stronger evidence of threat effects is found in the experience of deregulated industries where regulation was a central factor in union strength

portfolio choice with non expected utility in continuous time non expected utility preferences which can distinguish intertemporal substitution from attitudes towards risk are extended to continuous time the consumption savings and portfolio problem is solved for constant intertemporal elasticity of substitution and constant relative risk aversion

the soft underbelly of development demographic transition in conditions of limited economic change population policy is driven by two sets of theories which are examined here the first demographic transition theory proclaims the inevitability of a global transition from high to low birth and death rates as a world society and economy develop experience to date supports this generalization but researchers have had little success in identifying threshold socioeconomic or demographic indexes that would predict the onset of fertility decline the second demographic economic theory predicts that slower population growth rates will lead to faster rises in per capita income the historical evidence does not confirm these predictions however this paper examines the case of sub saharan africa where mortality has been falling consistently although often driven more by educational and other social changes than by rising incomes or enhanced medical care and halted only by war and civil disorder however declining fertility in sub saharan africa is not a certainty despite population projections by international organizations that assume that widespread decline is imminent evidence indicates that african fertility is peculiarly sensitive to infant and child mortality levels and therefore amenable to decline through service intensive combined health and family planning programs but it is not clear that governments can implement such programs on a national scale on the demographic economic nexus some evidence suggests that in sub saharan africa high levels of natural population increase do slow growth in per capita income family planning programs might also catalyze changes in family social and economic structures that would contribute to faster economic growth finally as the full scale of the african aids epidemic becomes clearer it will come to dominate all other population related concerns creating a compelling case for huge expenditures on comprehensive health family planning and social services aimed at reducing mortality curing sexually transmitted diseases detecting hiv infection and providing follow up services

economic models for the environmental kuznets curve a survey abstract the environmental kuznets curve ekc refers to an inverted u shaped relationship between some pollutant level and per capita income i e the environmental quality deteriorates at early stages of economic growth and subsequently improves at a later stage since the early 1990s a considerable number of empirical studies have been conducted on the ekc and although there is no conclusive proof it has been recognized that the ekc emerges as an empirical regularity however some recent studies cast doubt on the concept and methodology of empirical results and evidence of the existence of the ekc has been questioned in fact how economic growth affects the environmental quality i e the shape of the ekc is still controversial in order to identify the actual relationship between the environmental quality and economic growth it is essential to develop economic models from various points of view this paper overviews the current stage of theoretical models that explain such relationship

estimating the effects of unions on wage inequality in a panel data model with comparative advantage and nonrandom selection this article considers the estimation of the structure of wages in union and nonunion sectors it proposes an estimator that extends standard panel data techniques to the case in which the return to the permanent component of the error term is differently rewarded in the two sectors the econometric model is used to estimate the effect of unions on both the level and the variance of wages in canada the findings indicate that unions increase the average wage of workers and compress the returns to observable measures of skill and to a time invariant unobservable measure of skill

sustainable growth and the environmental kuznets curve abstract this paper develops an endogenous growth model with pollution and both human and physical capital human capital is produced cleanly and physical capital can be used for pollution control economic growth is sustainable in the long run it is optimal for human capital to grow more rapidly than physical capital output and consumption while pollution declines for realistic parameter values our results differ sharply from stokey s result for an ak technology that sustained economic growth is not optimal the model can generate an environmental kuznets curve a pollution tax or a voucher system can implement the pareto efficiency solution

technical progress structural change and the environmental kuznets curve abstract the paper shows that under reasonable assumptions about technical progress a positive sustainable growth rate fails to exist the argument is that a growing part of income has to be spent for continuing technical progress in order to compensate the pollution effects of growth hence in the long run either the sustainability condition will be violated or the growth rate must decline to zero furthermore in finite time the level of wealth will decrease despite growing income and a constant pollution level thus further growth is no longer reasonable similar arguments also hold for the environmental effects of structural change favoring less pollution intensive economic activities an evolutionary change of goods and production technology may shift the limits of growth and is hence a prerequisite for a long run ekc

models as usual for unusual risks on the value of catastrophic climate change we study the role of alternative intertemporal preference representations in a model of economic growth stock pollutant and endogenous risk of catastrophic collapse we contrast the traditional discounted utility model which assumes risk neutrality with respect to intertemporal utility with a multiplicative choice model that displays risk aversion in that dimension first we show that both representations of preferences can rationalize the same business as usual economy for a given interest rate and no pollution externality second once we introduce a collapse risk whose hazard rate is a function of the pollution stock multiplicative preferences recommend a much more stringent policy response an illustration in the context of climate change indicates that switching to the multiplicative preference representation has a similar effect in terms of policy recommendations as scaling up the schedule of the hazard rate by a factor of 100

a new econometric model of union threat effects the union threat effect is the propensity of non union employers to resist union organization by raising wages this study introduces an empirical model of the non union employer s optimal wage in the presence of threat effects estimates of an equation of a firm s unionization probability provide key variables unlike previous models this specification dervies directly from a theoritical model separstes threat effects from the influence of other union non union spillovers and efficiency wages and includes many factors affecting the probability of unionization wage equation estimates reveal that the predicted threat of unionization did not significantly raise non union wages in the united states in 1980

the effect of unions on the employment of blacks hispanics and women to investigate whether unions have helped or hindered the employment prospects of minorities and women the author analyzes data on 1 273 california manufacturing plants for the period 1974 80 the

procreation fishing and hunting renewable resources and dynamic planar systems many problems in the economics of renewable resources can be put in the form of a dynamic planar system this paper provides analytic and graphical methods for the study of the global dynamics existence of stationary points and local stability properties of such systems and applies these methods to problems of 1 population and environmental quality 2 exploitation of a stock of fish and 3 the economics of the pleistocene extinctions and the origins of agriculture

a bivariate probit approach to the determination of employment a study of teen employment differentials in los angeles county following a bivariate probit approach and using the 1990 public use microdata samples pums for los angeles county this study shows that the employment of teenage workers depends on both the worker s participation decision as well as the employer s hiring decision omission of the role of participation decision from the estimation of employment probability yields misleading evidence of hiring discrimination against blacks this evidence however disappears when the participation and hiring equations are estimated jointly in a bivariate framework the study finds no evidence of discrimination against females and latinos in addition the study shows that family household and neighbourhood characteristics play significant roles in the determination of teen employment

economic growth and the diffusion of clean technologies explaining environmental kuznets curves the paper provides a theoretical explanation for the inverted u shaped relation between pollution and income often found in empirical research environmental kuznets curve we model the transition in the pollution pattern as a change in general purpose technologies and investigate how it interferes with economic growth driven by quality improvements we provide an analytical foundation for the claim that the rise and decline of pollution can be explained by endogenous innovations policy induced technology shifts and intrasectoral changes once environmental degradation becomes too severe regulation is introduced by which society forces the economy to make a transition to cleaner production

handbook of natural resource and energy economics allan v kneese and james l sweeney eds vol ii north holland amsterdam 1985 d fl 215 00

wages experience and seniority in this paper we study the sources of wage growth we identify the contribution to such growth of general sector specific and firm specific human capital our results are interpretable within the context of a model where the returns to human capital may be heterogeneous and where firms may offer different combinations of entry level wages and firm specific human capital development we allow for the possibility that wages are match specific and that workers move jobs as a result of identifying a better match to estimate the average returns to experience sector tenure and firm specific tenure within this context we develop an identification strategy which relies on the use of firm closures our data source is a new and unique administrative data set for germany that includes complete work histories as well as individual characteristics we find positive returns to experience and firm tenure for skilled workers the returns to experience for unskilled workers are small and insignificant after 2 years of experience their returns to sector tenure are also zero however their returns to firm tenure are substantial in this paper we study the growth of wages of young workers in germany knowing the extent and reasons for individual wage growth over the life cycle is important for a number of areas in economics just to mention two examples first it is a key element to understanding and designing active labour market programmes many such programmes offer temporary and often subsidized work opportunities examples are the new deal in the u k and the swedish programmes as well as a number of programmes in germany these programmes are based on the assumption that general skills are sufficiently enhanced while working so as to render the workers employable without a wage subsidy thus the success of these programmes depends on how skills improve on the job for the target population and whether this skill enhancement is transferable across jobs second it is a key to understanding the benefits and costs of job mobility this in turn matters for a number of policy issues including the design of pension policies relating for example to final salary schemes as a result of this widespread interest a large body of empirical research has focused on obtaining estimates for the returns of experience and seniority 1 our study uses a new and unique administrative data set with a number of features that are important for our analysis and allow us to avoid many problems encountered in earlier work in this field in our model wages grow due to learning by doing which may be heterogeneous across individuals moreover since firms offer different career profiles and because we allow for match specific effects on wages investments take the form of searching for the firm with the most desirable learning by doing characteristics career structure 2

union wage hours and earnings differentials in the construction industry full information maximum likelihood is used to estimate union wage hours and earnings markups construction union wage markups are positive 58 2 at the sample means since union hours markups are negative 4 0 for most demographic groups union earnings markups 51 1 are smaller than the wage markups all exogenous variables are allowed to interact with the endogenous union dummy variable which allows us to test whether markups vary across demographic groups whether increased local unionization has a positive spillover effect in the nonunion sector and whether increased local unemployment equally affects wages and hours in increased local unemployment equally affects wages and hours in the two sectors

the environmental kuznets curve and flow versus stock pollution the neglect of future damages in this paper we offer a possible explanation for the empirical finding that the pollution income relationship pir for flow pollutants is an environmental kuznets curve ekc i e inverted u shaped but that the pir for stock pollutants is monotonically rising we analyse an overlapping generations model with two pollutants the flow pollutant causes immediate damages but the stock pollutant harms the environment only in the future hence a succession of myopic governments lets stock pollution grow with income in contrast the flow pollutant follows an ekc whose downturn might be caused by the neglect of future damages and by ever rising stock pollution without the stock pollutant the pir for the flow pollutant can increase monotonically we also show that the turning point of the ekc for the flow pollutant lies at lower levels of income and of flow pollution if stock pollution is high and harmful this casts doubts on most empirical ekc studies because they assume that the turning point occurs at the same income level in all countries however it is consistent with recent empirical findings that the income level at the turning point of the ekc varies across countries

union wages and union decline evidence from the construction industry two well documented empirical findings are that unionized employees typically receive substantially higher compensation than their non union counterparts and that union representation in the united states has declined over time some observers have hypothesized a causal link between these two phenomena the achievement of a union wage premium they argue hastened union decline both by reducing union firms economic competitiveness and by inducing employers to adopt various union avoidance strategies using data from the current population survey and the census bureau s census of construction the authors test this hypothesis for the construction industry even in estimations that allow for a lagged response and incorporate a variety of controls they find no evidence that high union nonunion wage ratios in construction in the 1970s or 1980s resulted in lower union membership in 2000

the rising skill premium and deunionization abstract during the past 50 years the us economy has seen a rapid decline in labor union membership and a substantial rise in wage inequality since labor unions compress wages between skilled and unskilled workers a rising skill premium encourages skilled workers to withdraw from the union if this withdrawal is accompanied by a fall in the productivity of unskilled workers firms become reluctant to hire the relatively expensive union workers reinforcing the decline in the unionization rate evaluating this hypothesis we find that the rise in the skill premium explains about 40 of the decline in the unionization rate

is trade good or bad for the environment sorting out the causality we seek to contribute to the debate over globalization and the environment by asking what is the effect of trade on a country s environment for a given level of gdp we take specific account of the endogeneity of trade using exogenous geographic determinants of trade as instrumental variables we find that trade tends to reduce three measures of air pollution statistical significance is high for concentrations of so2 moderate for no2 and lacking for particulate matter although results for other environmental measures are not as encouraging there is little evidence that trade has a detrimental effect on the environment

the determinants of workers union status evidence from the national longitudinal surveys using data from the 1980 wave of the young men nls sample this paper provides estimates of the queue model developed by farber to explain the process of union status determination the use of nls data largely avoids the censoring problem encountered by farber in estimating his model and permits direct estimation of crucial probabilities associated with the model despite important differences between econometric methodologies and the data sets analyzed the nls results support farber s conclusion that queueing for vacancies in existing union jobs is an important labor market phenomenon in particular supply constraints on the availability of union jobs are found to dominate worker preferences in explaining differences in extent of unionization by occupation and region but not race

union status of young men in britain a decade of change previous empirical studies of individual union status in britain have been cross sectional in contrast we use longitudinal data from the national child development study to estimate the determinants of male trade union membership over the period 1981 1991 as suggested by union theories we find that it is important to control for unobserved individual heterogeneity and our preferred model allows for correlation of individual heterogeneity with observable variables our estimates reveal that the observed decline in very large workplaces and the contraction of the public sector explain about one third of the predicted decline in union membership over the period

reexamining the empirical evidence for an environmental kuznets curve this paper uses an updated and revised panel data set on ambient air pollution in cities worldwide to examine the robustness of the evidence for the existence of an inverted u shaped relationship between national income and pollution we test the sensitivity of the pollution income relationship to functional forms to additional covariates and to changes in the nations cities and years sampled we find that the results are highly sensitive to these changes and conclude that there is little empirical support for an inverted u shaped relationship between several important air pollutants and national income in these data

inequality and attainment in a dual labor market models of wage determination and sector attainment are estimated for a cohort of young men in a dual labor market neoclassical economic vs dual labor market views on market equilibrium are contrasted although schooling is rewarded similarly in the primary and secondary sectors other results support the dual labor market view that employment in the primary sector is rationed via a queuing mechanism

are there increasing returns to pollution abatement empirical analytics of the environmental kuznets curve in pesticides abstract according to the environmental kuznets curve ekc hypothesis economic growth and the reduction of environmental degradation are compatible goals an inverted u shaped relationship between economic performance and environmental pollution suggests that empirically an economy is associated with smaller levels of pollution after some threshold income point one potential explanation for the empirical evidence of an ekc is increasing returns to pollution abatement where the abatement efficiency rises with an increase in the scale of abatement doubling the clean up efforts more than doubles the abatement of pollution as this efficiency gain makes abatement less expensive pollution might fall as more abatement is undertaken this study tests the hypothesis that there are increasing returns to abating pollution empirical evidence on environmental risks in the us agricultural sector since 1970 support the existence of increasing returns in addition i estimate the productivity of pollution abatement using refined empirical productivity measurement methods and explicitly control the level of technology the results show the importance of including an environmental productivity variable in the ekc framework

are low skill public sector workers really overpaid a quasi differenced panel data analysis public private sectoral wage differentials have been studied extensively using quantile regression techniques these typically find large public sector premiums at the bottom of the wage distribution this may imply that low skill workers are overpaid prompting concerns over efficiency we note several other potential explanations for this result and explicitly test whether the premium varies with skill using australian data we use a quasi differenced generalized method of moments gmm panel data model which has not been previously applied to this topic internationally unlike other available methods this technique identifies sectoral differences in returns to unobserved skill it also facilitates a decomposition of the wage gap into components explained by differences in returns to all observed and unobserved skills and by differences in their stock we find no evidence to suggest that the premium varies with skill one interpretation is that the compressed wage profile of the public sector ind

a selectivity model of employer size wage differentials this article investigates wage differentials for employees of different size firms utilizing an econometric methodology that allows the size of employer to be treated as endogenous in the context of discrete ordered employer size data as a result we are able to estimate i employer size wage gaps which are corrected for selectivity bias and ii the magnitude and direction of the selection bias decompositions of the resulting wage differentials are computed with comparisons of the conditional on sorting across employer size and unconditional wage gaps

reproductive externalities and fertility behaviour abstract this article studies reproductive externalities within rural communities in poor countries it is shown that such externalities create a link between household poverty household size and the local natural resource base each of which is viewed as being endogenous the models presented here offer an explanation for the fact that in recent decades large groups of people in various parts of the world have been unable to lift themselves out of acute poverty even while their national economies have on average enjoyed economic growth implications for policy and institutional changes are drawn

the effect of unionism on fringe benefits this study analyzes the impact of unionism on fringes paid to production workers using data on individual establishments it compares fringe expenditures in establishments having the same level of compensation per hour and finds that unionism raises the share of compensation allotted to fringes particularly to pensions vacation pay and life accident and health insurance in addition since unionism also raises the straight time wage rate itself a prime determinant of expenditures on fringes unionism has a very sizeable impact on total fringe expenditures as well as on the fringe share of compensation the union fringe effect exceeds in percentage terms the union wage effect and is sufficiently large to suggest that standard union wage studies understate the union effect on total compensation the study also compares the fringe expenditures of production and non production workers within the same establishment controlling for within establishment pay policies the findings suggest that the pres

rare disasters asset prices and welfare costs a representative consumer model with epstein zin weil preferences and i i d shocks including rare disasters accords with observed equity premia and risk free rates if the coefficient of relative risk aversion equals 3 4 if the intertemporal elasticity of substitution exceeds one an increase in uncertainty lowers the price dividend ratio for equity and a rise in the expected growth rate raises this ratio calibrations indicate that society would willingly reduce gdp by around 20 percent each year to eliminate rare disasters the welfare cost from usual economic fluctuations is much smaller though still important corresponding to lowering gdp by about 1 5 percent each year

total factor productivity and the environmental kuznets curve abstract empirical studies support the environmental kuznets curve hypothesis ekc for some pollutants as income increases pollution increases reaches a peak and eventually decreases while relying mostly on cross sectional data the interpretations assert that the ekc is a by product of economic growth over time in doing so and in neglecting the role of important country specific characteristics these studies overlook potential econometric problems and introduce policy misconceptions differences in total factor productivity tfps account for much of the variation in income across countries with important implications for environmental quality we develop a theoretical model where different tfps produce a cross sectional ekc even if the dynamic path of environmental quality to its steady state in individual countries suggest otherwise the cross sectional ekc depends on diminishing returns to scale in environmental protection on the curvatures of the utility function with respect to consumption and of the environmental protection function and the elasticities of steady state consumption and environmental expenditures with respect to variation in tfps

climate change and uneven development in this paper using a theoretical model with endogenous capital depreciation we study the effects of climate change and adaptation on long run development we show that climate change affects economic growth depending on climate exposure and adaptation efficiency which are asymmetric between different countries poor countries are likely to be hurt more because of the negative effects of climate change on the rate of depreciation of the assets that represent the engine of growth these asymmetries generally induce growth deficits and unsustainability traps in less developed economies

a tradable permit system in an intertemporal economy it is known that in an intertemporal competitive economy a tradable permit system may not achieve efficiency without setting appropriate permit interest rates i e rewards for holding permits to find the rates however we need to know in advance the path of efficient permit prices which is difficult to obtain this study intends to solve this problem in two ways first we analyze a special case in which the permit interest rates are given by a simple rule for example if the marginal abatement cost of pollution emission is constant then the appropriate rate is to equal the monetary interest rate as is the case for global warming if the damage is caused in the future far beyond the planning period of the environmental program the appropriate rate coincides with the marginal self recovery of environmental stock under certain conditions as a second approach we propose a tradable permit system with a permit bank as a mechanism by which the permit interest rates are generated endogenously without governmental intervention other than the issuance of permits however we also show that this approach raises the problem of indeterminacy of the equilibrium

labor unions and the distribution of wages and employment in south africa few countries have higher wage inequality than south africa where wages of african and white workers differ by a factor of five using survey data collected in 1993 the authors analyze the complex effect of unions on this wage gap among male african workers in the bottom decile of the wage distribution union membership was associated with wages that were 145 higher than those of comparable nonunion workers and among those in the top decile the differential was 19 regression estimates also indicate that returns to observed productive characteristics of workers such as education and experience were larger for nonunion than union workers if the large union relative wage effect were cut in half the authors estimate that employment of african youth age 16 29 would increase by two percentage points and their labor force participation rate would also increase substantially

assessing income population and technology impacts on co2 emissions in canada where s the ekc abstract this study investigates the macroeconomic forces underlying carbon dioxide co2 emissions from fossil fuel use in canada in keeping with the relevant literature on environmental degradation three forces are expected to influence co2 emissions gross domestic product per capita gdp capita population and technological change while previous work has employed reduced form models that allow for non linear relationships between co2 and gdp capita it has been common practice to assume linear relationships between co2 and the latter two variables this study tests a more flexible model using a five region panel data set in canada over the period 1970 2000 findings indicate that gdp capita is unrelated to co2 that an inverted u shaped relationship exists with population and that a u shaped relationship exists with technology thus technological and population changes are supported over the commonly hypothesized environmental kuznets curve an inverted u shaped relationship between gdp capita and environmental degradation for affecting co2 emissions from fossil fuel use in canada

credit market constraints consumption smoothing and the accumulation of durable production assets in low income countries investments in bullocks in india in this paper we formulate and estimate a finite horizon structural dynamic model of agricultural investment behavior that incorporates the major features of low income agricultural environments income uncertainty constraints on borrowing and rental markets and the use of investment assets to generate income and smooth consumption the model is fit to longitudinal indian household data on farm profits bullock stocks and pump sets the estimated structural parameters are used to assess the effects on the life cycle accumulation of bullocks agricultural profits and welfare associated with complete markets and bullock liquidity and with second best policies that provide assured sources of income to farmers and weather insurance

on measuring the quality of life abstract it is widely recognized that per capita income is not an adequate indicator of aggregate well being it has thus become customary to use a range of socioeconomic indices for assessing the quality of life in a society in this article we extend measures of general well being in current use by including ordinal indices of political and civil liberties and we provide a ranking of the world s poorest countries on the basis of the borda rule we then compare improvements in socioeconomic performance with the availability of political and civil liberties during the decade of the 1970s and observe that improvements in per capita national income life expectancy at birth and infant mortality are positively correlated with the extent of political and civil liberties enjoyed by citizens while improvements in literacy are negatively correlated with these liberties

the role of the desire for union status in the decision to enter local government job queues the us evidence following a two stage bivariate probit approach this study estimates local government and union job queues in a simultaneous equations framework by relaxing the restrictive assumption of independence between the worker s queuing and the employer s hiring decisions it overcomes a major limitation of most of the earlier job queue estimates the results indicate that the worker s queuing decision for local government jobs in the united states is determined partly by the desire for unionized employment the converse however is not true seniority with the current employer emerges as a significant determinant of both workers queuing and employers hiring decisions furthermore local governments act as model employers by being more likely to hire minorities and females from the pool of job applicants

an empirical investigation of rationing constraints in rural credit markets in india abstract the literature on rural credit markets has generally assumed that households are rationed in their access to subsidized formal credit the validity of this assumption depends on the level of effective demand for formal credit in turn a function of the demand for credit and its availability from informal sources this paper estimates the demand and the sector specific costs of credit and hence the extent of formal sector rationing through an analysis of household participation in both the formal and the informal credit sectors the results show that the extent of rationing is considerably less than what is conventionally assumed

sustainability limited substitutability and non constant social discount rates abstract the paper shows how limited substitutability in consumption between different classes of goods affects the magnitude and time development of social discount rates it decomposes the discount rates into an absolute growth and a relative growth or substitutability effect the paper relates between good and intertemporal substitutability to the notions of weak and strong sustainability it analyzes under which circumstances low as opposed to high between good substitutability increases the weights given to long run environmental services

do unionized firms hire better workers i introduction many economists firmly believe that union firms offset higher union wages by hiring better workers the contrasting view that union employers react to higher union wages by hiring poorer quality workers is regarded as impossible 1 yet this contrasting view is highly plausible in the context of standard economic modeling and with what is known about labor markets there is evidence supporting this view the standard story for unionized firms hiring better workers goes like this a union raises wages and the firm foils the union by hiring better quality workers the problem with this myopic story is that it ignores what happens in the future it assumes that unions will sit idly by and let union firms whittle away any union wage differential by hiring better quality workers i would argue that it is more likely that unions would respond to better quality workers by raising wages even more employers anticipating this may respond by hiring lower quality workers this article is the first to consider how unionized firms choose worker quality when they anticipate the future consequences of quality on wages under reasonable conditions these consequences cause employers to hire lower quality workers while i do not contend this always occurs i do argue that there are reasonable grounds for rejecting the better quality proposition in addition there is evidence that unionization often does result in lower quality workers the results presented here suggest that economists should look again at how unions affect wages productivity equality and society this is not the first paper to suggest unions lead to lower quality workers it is however the first to suggest this result is due to employers making profit maximizing decisions when they anticipate the future consequences of their actions there are two other articles that also suggest unions can lead to lower quality workers first robinson 1989 assumes that unionized employers do want higher quality workers but do not hire them because nonunion firms pay them more as the nonunion firms are assumed to have better monitoring technology and a more flexible reward system second bronars and lott 1989 show that unions that seek the maximum dues will want poorer quality workers while these models focus on factors that may prove to be important the model presented here is theoretically more forceful first it is based upon standard economic modeling second using ochkam s razor it assumes the least added factors and finally its central assumption that people anticipate the future has a large body of economic evidence behind it by demonstrating that the better quality proposition is not supported by conventional economic analysis this article shows the better quality proposition should not be given a greater weight in the priors of economists having done this these other models then should and hopefully will be examined more closely ii the case for unions leading to better quality workers in discussing the wage gap between union and nonunion workers h gregg lewis 1986 46 concisely presents the case that union firms select better workers i have strong priors on the direction of the selectivity bias let a union through collective bargaining impose on an employer higher wages for his workers than he otherwise would pay them with worker quality not tightly specified in the collective bargaining agreement the higher wages will lengthen the queue of the applicants for the unionized jobs including some applicants of greater productiveness than otherwise would have applied the employer has an incentive to evade the increase in his labor costs by employing workers of greater quality the evasion will take time and will be impeded by the cost of screening workers imperfect substitution in production among worker quality and employment constraints in the collective bargaining agreements

starting even job mobility and the wage gap between young single males and females standard econometric analysis of male female earnings differentials ignores job mobility despite its vital role in theories of discrimination and its demonstrated importance in explaining the earnings of young men this paper develops a model of male and female earnings and job mobility and estimates it for young single men and women in canada using the 1981 survey of work history the results corrected for sample selection bias arising from job mobility suggest that male and female earnings determination differs considerably by job mobility status returns to mobility are much greater for males than for females the results also show significantly different mobility behaviour for men and women but if anything females are more mobile than males faced with the same earnings opportunities thus differential job mobility behaviour does not appear to account for any portion of the male female earnings gap

global warming discounting is not the issue but substitutability is the cost benefit study of nordhaus 1994 is representative for the neoclassical approach towards global warming nordhaus found that no substantial emission cuts are warranted most of his critics have concentrated on the issue of discounting and demanded that a lower discount rate should be applied these criticisms first miss the point and second lead to ethically dubious inconsistent conclusions and inefficient policy choices they miss the point because the real problem of nordhaus s methodology is his implicit underlying assumption of perfect substitutability between natural and other forms of capital given the validity of this assumption lowering the rate of discount is inconsistent with current savings behaviour is ethically dubious because future generations will be much richer than the current one anyway and is inefficient because scarce financial resources are channelled into emissions abatement that exhibits rates of return far inferior to alternative public investments any call for aggressive emission abatement must therefore directly attack the perfect substitutability assumption of neoclassical economics the real disagreement is about whether consumption growth can compensate for environmental degradation caused by global warming discounting is not the issue but substitutability is

returns to seniority in union and nonunion jobs a new look at the evidence in cross sectional data the positive association between seniority and earnings is typically much stronger for nonunion workers than for union workers a finding that seems inconsistent with the generalization that seniority is more important in the union sector than in the nonunion sector the authors of this paper show that standard estimates of the return to seniority are likely to be biased upward due to unmeasured worker heterogeneity job heterogeneity or both and they argue that this bias is likely to be larger in the nonunion sector than in the union sector when they correct for this problem in analyzing data on male blue collar workers for the years 1968 80 they find a larger return to seniority in the union sector than in the nonunion sector

scarcity growth and r d abstract the limits to economic growth due to resource scarcity can be alleviated only by the development of backstop substitutes this paper combines resource based economic growth with r d to reduce the cost of backstop technologies characterizing the entire dynamics of optimal growth and r d processes we find that an economy s growth prospects depend on its type as determined by its production technology and learning ability and by its knowledge capital endowment a wide variety of growth patterns emerges ranging from cases in which an economy that without r d eventually stagnates converges to a steady state is diverted by r d onto a path of sustained growth to cases in which r d is not warranted resource scarcity is shown to encourage r d due to the increased reliance on the backstop technology

vulnerable seniors unions tenure and wages following permanent job loss in contrast to nonunion workers reemployment wages of workers displaced from unionized jobs decline with tenure on the lost job this finding cannot easily be explained by firm or industry specific human capital accumulation deferred pay policies standard matching models or a correlation between tenure and reentry rates into unionized jobs possible explanations include negative selection of senior union workers and a negative causal effect of unionism on workers alternative skills despite a much flatter predisplacement tenure wage profile displaced union workers wage losses increase with tenure at a rate comparable to or higher than those of nonunion workers

population growth externalities to childbearing and fertility policy in developing countries government financed family planning programs that assist individual couples to attain their desired number of children are easily justified but government policies that coerce or use financial incentives to influence couples to alter their desired number of children require stronger justification such justification may reside in the externalities to childbearing the costs and benefits of children that are passed on by parents to society externalities to childbearing might include public costs of education health and pensions as well as taxes to be paid by children in the future cost sharing for public goods and social infrastructure over an enlarged tax base the dilution of per capita value of various forms of collective wealth and the reduction of wages and per capita incomes in the future the authors estimated these externalities for a number of developing countries although the net total estimated externality was typically negative it dominated measurement error only when public holdings of natural resources were important public expenditures on health education and pensions financed by proportional taxes led to negative externalities in most developing countries there are many sources of positive and negative externalities and each estimate is uncertain so the total externality is itself highly uncertain and often does not provide a clear case for policies going beyond family planning inclusion of environmental effects might alter this conclusion

the effect of unions on wage inequality in the u s labor market this study uses current population survey micro data for 1973 74 and 1993 to evaluate the effect of changing union membership on trends in male and female wage inequality unionization rates of men fell between the two sample periods with bigger declines among lower skill groups these trends account for 15 20 of the rise in male wage inequality union membership rates of low wage women also declined while unionization increased among higher wage women on balance shifting unionization accounts for very little of the rise in female wage inequality economy wide trends in unionization mask a sharp divergence between the private sector where unionism was declining and the public sector where it was rising comparisons across sectors suggest that unionization substantially slowed the growth in wage inequality in the public sector

the economics of poverty in poor countries this paper which examines recently studied links between 1 poverty high fertility and undernourishment and 2 environmental degradation and civic disconnection in developing countries opens by reviewing the limitations of orthodox discussions of economic institutions and property rights and the orthodox dichotomy that has located the cause of poverty in the suppression of markets the introduction also notes that much of the analysis in this paper is based on data from sub saharan africa and india the next section of the paper summarizes evidence on the magnitude and extent of world poverty section 3 exposes the connection between undernourishment and a persons capacity to work as one of the pathways to the poverty trap sections 4 and 5 consider the dependence of impoverished rural populations on common property resources and how the conventional process of economic growth can break down this system and make certain sections of the population especially vulnerable to economic shocks the next two sections explore the possibility that links between poverty high fertility and environmental degradation may constitute another pathway to the poverty trap the eighth section reviews the methodology of using net national product which includes resource depletion and environmental deterioration as an evaluation criterion and argues that mainstream development economists may have neglected environmental and population problems because they have been relying on the wrong economic indices the final section concludes that a number of policies must be used to improve options for people

the decline of unionization in the united states what can be learned from recent experience the dramatic decline in unionization over the last decade is investigated in the context of a supply demand model of union status determination using data from surveys of workers conducted in 1977 and 1984 along with data from the national labor relations board on representation elections it is concluded that the decline in unionization since 1977 is accounted for largely by 1 an increase in employer resistance to unionization probably due to increased product market competitiveness and 2 a decrease in demand for union representation by nonunion workers due to an increase in the satisfaction of nonunion workers with their jobs and a decline in nonunion workers beliefs that unions are able to improve wages and working conditions

intra industry trade in intermediate products pollution and internationally increasing returns this paper examines the relationship between intra industry trade in intermediate products pollution and increasing returns we develop a two country model in which production occurs in two stages final and intermediate good production intermediate goods are produced under monopolistic competition and final good production exhibits increasing returns with respect to the number of varieties of intermediates pollution occurs in the production of the final good when polluting intermediates are used we analyze the effects of international trade in intermediate products on pollution output and welfare under an endogenous tax scenario and with two types of pollution functions the results show that because of increasing returns international trade either leads to lower total pollution in each country or lower pollution per unit of output in at least one country in addition intra industry trade causes countries to import the environmental quality of their trading partners

economic growth and environmental degradation when preferences are non homothetic we study the dynamics of pollution in an economic growth model with non homothetic preferences we characterize the forces that may drive the evolution of the income pollution relationship along the development process in particular we disentangle the standard accumulation mechanism which determines the intertemporal allocation of pollution from a mechanism based on the non homotheticity of preferences which leads the intratemporal allocation of expenditure between consumption and pollution abatement to depend on income as the economy develops and aggregate income grows up the fraction of income devoted to abatement increases if the income elasticity of abatement is larger than unity in this case the pollution may decrease with income even when the elasticity of pollution with respect to abatement is smaller than the elasticity of pollution with respect to emissions we numerically illustrate how this demand based mechanism determines the dynamic relationship between pollution and aggregate income

a tale of two elasticities a general theoretical framework for the environmental kuznets curve analysis abstract we show that a variety of seemingly diverse concepts used to theoretically explaining the ekc have a common origin in two key preference and production elasticities we also prove that they jointly correspond to a unique underlying preference technology theoretical framework

voting for pollution policy the importance of income inequality and openness to trade abstract this paper analyzes how openness and the distribution of factor ownership interact to determine individual and aggregate demand for pollution policy analysis of voter preferences in autarky shows that an increased stake in either the dirty or the clean industry can induce an individual voter to prefer stricter environmental policy similarly the paper shows that poorer voters may be the greener voters within an electorate the model also reveals that the incidence of pollution policy depends upon a country s trade regime with consequences for the direction in which income inequality influences aggregate demand for pollution policy

migration age and earnings the special case of employee transfers the regional relocation of workers within firms is examined this aspect of migration has received little attention in spite of the routine occurance of employee transfers the existence of such transfers suggests that a portion of each worker s human capital is employer specific and readily transferrable across locations thus a different age profile for transfers than that for conventional migrants may be expected specially a model of employee relocation and the consequences of relocation on post transfer earnings is examined

politics vs economics evidence from municipal annexation abstract this paper investigates economic and political factors in suburban annexation decision in large u s cities this paper employs a median voter model which suggests a natural latent variable estimation strategy bivariate logit and normal procedures incorporating information about state laws governing annexation are run on census tract level data estimated parameters are used to evaluate the effects of economic and political variables results show cities desire to expropriate suburban tax base did not motivate annexation although cities were sensitive to other economic factors the desire to offset political and racial effects of urban migration had a consistent and positive effect on annexation

the environment and emerging development issues development economics for the most part has failed to recognize renewable environmental resources as economic goods yet the lives of the poor in developing countries are intimately tied to the fate of their local common property resources soil fuel wood water and so on ignoring the loss of common property renewable resources via degradation centralization or privatization in calculations of net national product can mask the destruction of resources available to a country s poor behind the false appearance of a growing national economy this paper describes the difference between the problem of managing local common property resources in developing countries and the problem of protecting the global commons such as the atmosphere and oceans it outlines the calculations that would include the local commons in the national income accounting of capital assets and argues that the interests of those most dependent on the increasingly scarce local commons will be best served by placing control in their hands while the central government provides infrastructure and educational support to control the pollution of the global commons on the other hand the paper sketches a plan in which most countries would have a high incentive to participate a global allocation of limited tradable permits to discharge defined pollutants

federal and union job queues further evidence from the us labour market recent research on union differentials suggests that although the premium to unionization is higher in the private sector it can hardly be ignored in the federal sector consequently the nature and length of the federal queue may differ between union and non union sectors similarly the union queue may not necessarily be homogeneous between federal and private sectors we estimate separate queues for federal union federal non union and private union jobs from the same sample this avoids the problem of simultaneity between the federal queue and the union queue in addition it explores several important differences that exist between these queues

confronting the environmental kuznets curve t he environmental kuznets curve posits an inverted u relationship between pollution and economic development kuznets s name was apparently attached to the curve by grossman and krueger 1993 who noted its resemblance to kuznets s inverted u relationship between income inequality and development in the first stage of industrialization pollution in the environmental kuznets curve world grows rapidly because people are more interested in jobs and income than clean air and water communities are too poor to pay for abatement and environmental regulation is correspondingly weak the balance shifts as income rises leading industrial sectors become cleaner people value the environment more highly and regulatory institutions become more effective along the curve pollution levels off in the middle income range and then falls toward pre industrial levels in wealthy societies the environmental kuznets curve model has elicited conflicting reactions from researchers and policymakers applied econometricians have generally accepted the basic tenets of the model and focused on measuring its parameters their regressions typically fitted to cross sectional observations across countries or regions suggest that air and water pollution increase with development until per capita income reaches a range of 5000 to 8000 when income rises beyond that level pollution starts to decline as shown in the conventional ekc line in figure 1 in developing countries some policymakers have interpreted such results as conveying a message about priorities grow first then clean up numerous critics have challenged the conventional environmental kuznets curve both as a representation of what actually happens in the development process and as a policy prescription some pessimistic critics argue that crosssectional evidence for the environmental kuznets curve is nothing more than a

neoclassical growth the j curve for abatement and the inverted u curve for pollution abstract this paper reexamines the neoclassical environmental growth model of forster to gain insights into the dynamic relationships among pollution abatement effort and economic development whereas the model has heretofore been used to examine steady state levels of capital consumption and environmental quality it also provides a theoretical basis for recent empirical research on j curves for abatement effort and inverted u curves for pollution

multiple equilibria in a stochastic implementation of dice with abrupt climate change abstract integrated assessment modeling of global climate change has focused primarily on gradually occurring changes in the climate system however atmospheric and earth scientists have become increasingly concerned that the climate system may be subject to abrupt discontinuous changes on short time scales and that anthropogenic greenhouse gas emissions could trigger such shifts incorporating this type of climate dynamics into economic or integrated assessment models can result in model non convexity and multiple equilibria and thus complicate policy analysis relative to models with unique globally optimal policies using a version of the nordhaus dice model amended in previous research by keller et al 2004 keller klaus benjamin m bolker david f bradford 2004 uncertain climate thresholds and optimal economic growth journal of environmental economics and management 48 1 723 741 in conjunction with a stochastic global optimization algorithm we generate level sets of solutions which helps identify multiple equilibria resulting from the potential abrupt cessation of the north atlantic thermohaline circulation we discuss the implications of this model geometry for formulating greenhouse gas abatement policy under uncertainty and suggest that this general approach may be useful for addressing a wide range of model non convexities including those related to endogenous technological change

nonhomothetic growth models for the environmental kuznets curve we show the role of the elasticity of substitution between general consumption and the environment in environmental degradation specifically our numerical experiments demonstrate for a wide range of models exponential utility generates the environmental kuznets curve without adding any special assumptions with exponential utility the elasticity of substitution and hence the substitution effect between consumption and the environment are both decreasing in income hence when income is low society the government readily gives up environmental quality in return for more consumption but it does not want to substitute consumption for the environment anymore once it becomes wealthy enough

the population problem theory and evidence this study is concerned with the relationships among population growth poverty and environmental degradation with particular focus on the situation in developing countries the author rejects the concept of a general theory of fertility behavior in favor of an interpretation of these relationships which might be applicable to certain situations in the poorest parts of the indian subcontinent and sub saharan africa such situations include unacceptable risks of maternal death for poor illiterate women and a condemnation to extreme poverty in conditions of the deterioration of local resources and of the environment the author concludes that population growth rates are too high in certain specific areas and that an appropriate policy reaction to such conditions would be to try to change the options that men and women face so that their reasoned choice would be to lower their fertility

output emissions and technology some thoughts abstract the principal goal of this article is to identify the implications of a binding emission constraint on a firm s optimal capital labor ratio and to determine whether it is appropriate to write a firm s production function as an increasing function of its emissions alone i find that even though a firm s supply curve may be written as a positive function of its emissions it is not appropriate to write the production technology as an increasing function of only its emissions except under special circumstances

are there limits to growth a simple theoretical model of pollution is developed that generates an inverted u shape relationship between per capita income and environmental quality this model is then used to study long run growth the same inverted u shape is shown to appear in time series and the prospects for sustained growth are shown to hinge on whether increasingly strict environmental regulation is compatible with a constant rate of return on capital implementation is also studied tax and voucher schemes are shown to have an advantage over direct regulation because they provide the correct incentives for capital accumulation copyright 1998 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

wealth varying intertemporal elasticities of substitution evidence from panel and aggregate data abstract this paper constructs and estimates a model of consumer preferences in which the intertemporal elasticity of substitution ies of consumption expenditure rises with the level of wealth the purpose of this paper is to measure the effect that systematic variation in the ies of poor and rich consumers has on the ies of aggregate consumption expenditure we find economically significant differences in the ies of poor and rich consumers in indian panel data on the consumption of individual households we also find economically significant differences in the ies measured in aggregate time series data for the u s and india

inequality as a determinant of malnutrition and unemployment policy this paper explores the policy implications that are obtained once it is recognized that at low nutrition intakes a person s productivity is an increasing function of intake in the context of a fully general equilibrium model it is shown that if aggregate assets in an economy are neither large nor small certain patterns of lorenz improving asset redistributions or nutrition transfers increase aggregate output and reduce the volume of involuntary unemployment and the incidence of undernourishment copyright 1987 by royal economic society

the impact of unionization on male female earnings differences in canada the impact of unionization on male female earnings differences in canada is analyzed using data spanning 1981 to 1988 a period in which the male female unionization gap narrowed considerably gender differences in union density union wages and nonunion wages are decomposed into characteristics related and discriminatory components we find that the drop in the gender unionization gap prevented an increase of 7 percent in the overall wage differential between men and women also male female earnings differences in the nonunion sector make a substantially larger contribution to the gender earnings gap than do those in the union sector

towards an integrated framework for development and environment policy the dynamics of environmental kuznets curves abstract environmental kuznets curves ekcs have recently received considerable attention in development and environment policy but little is known on how the interaction between ecological and economic factors may result in an ekc or other qualitatively different outcomes we introduce a restricted class of vector valued differential equations for representing the evolution of socioeconomic and environmental variables which influence or are influenced by the process of economic development our model includes not only the complete path of each variable over time but also the highly critical interactions among multiple variables we demonstrate analytically and numerically that among a multiplicity of possible outcomes an inverted u pattern can only be obtained under specific circumstances and requires attention to the multiple factors which form the economic environmental system rather than a single dominant one

the impact of changes in human fertility on poverty household survey data for developing and transitional economies are used to estimate the effect of fertility crude birth rate net of infant deaths on private consumption poverty cross national regressions indicate that higher fertility increases poverty both by retarding economic growth and by skewing distribution against the poor our median country in 1980 had dollar a day poverty incidence of 18 9 per cent had it reduced its fertility by four per 1 000 throughout the 1980s the sample median fall it is estimated that incidence would have been reduced to 13 9 per cent the growth and distribution effects being roughly equally responsible for this reduction

population and the environment a parable of firewood and other tales the author analyzes the relationship between population and the environment with a focus on the role which environmental degradation and natural resources depletion may play in producing the population pressure which lies behind such degradation and depletion especially in developing countries the principal conclusion of this analysis is that the possibilities for a stable equilibrium between human population and its environment are quite limited i show that parental altruism toward their children can only make matters worse if socially unchecked by leading to an increase of the birthrate in every environmental state in comparison with that which would occur in its absence excerpt

a dynamic model of the environmental kuznets curve turning point and public policy we set up a simple dynamic macroeconomic model with i polluting consumption and a preference for a clean environment ii increasing returns in abatement giving rise to an ekc and iii sustained growth resulting from a linear final output technology there are two sorts of market failures caused by external effects associated with consumption and environmental effort the model is employed to investigate the determinants of the turning point and the cost effectiveness of different public policies aimed at a reduction of the environmental burden moreover the model offers a potential explanation of an n shaped pollution income relation it is shown that the model is compatible with most empirical regularities on economic growth and the environment

why do workers join unions the importance of rent seeking union status models ignore the fact that rent seeking prospective members have an incentive to bid up entry costs so that higher union wage gains make union jobs more costly to obtain the standard presumption that higher union wages cause firms to substitute toward higher quality workers is shown to be incorrect under most plausible assumptions the observed positive correlation between wage gains and the propensity to join a union underestimates the size of the true supply response the union nonunion wage differential reveals more about the social cost of unions than the gain to an individual worker from union membership

the environmental kuznets curve does one size fit all abstract this paper uses a new panel data set on state level sulfur dioxide and nitrogen oxide emissions from 1929 1994 to test the appropriateness of the one size fits all reduced form regression approach commonly used in the environmental kuznets curve literature empirical results provide initial evidence that an inverted u shape characterizes the relationship between per capita emissions and per capita incomes at the state level parameter estimates suggest however that previous studies which restrict cross sections to undergo identical experiences over time may be presenting statistically biased results

status concern and the exploitation of common pool renewable resources we examine the impact of social status concern in a common pool renewable resource oligopoly a small number of players share access to a common pool resource and sell their production in a common market where they are oligopolists we depart from the mainstream literature on common pool resource oligopolies by considering that each player cares about her social status we allow for two channels to impact a player s welfare harvest and profits under the first channel a player has a bump in her utility when her harvest is larger than the average harvest of the rest of the players in this case we show that the presence of this channel exacerbates the tragedy of the commons under the second channel a player enjoys a bump in her utility if she manages to earn more profits than the average profits of the other players in this case we show that social status concern may temporarily alleviate the tragedy of the commons it results in a decrease of extraction over an interval of stock sizes

union membership determination and industry characteristics recent literature on the economics of unionism has expanded beyond its customary focus on the wage and nonwage effects of collective bargaining and given increased attention to the determinants of union membership previous union membership studies have been couched primarily within an individual choice framework whereby utility maximizing individuals choose either to join or not to join a union empirical work typically treats membership as a function of some vector of personal characteristics 1 2 10 11 21 it is our contention that such studies can best be interpreted as explaining the determination of the union status of jobs and that several industry and firm characteristics in addition to personal characteristics can be expected to affect significantly union membership in this paper theory and evidence relating to the effects of firm and industry characteristics on union membership are presented industry level data are bridged with a large microdata set containing individual characteristics in order to examine the determinants of unionism among workers in manufacturing utilizing a simultaneous model and controlling for sample selection bias we find that product market concentration capital intensity establishment size and job risk significantly affect the likelihood of union membership

preferences technology and the environment understanding the environmental kuznets curve hypothesis we derive a simple expression for the income pollution path using the standard static model of the environmental kuznets curve ekc this expression makes it straightforward to identify the general characteristics of utility and pollution functions that lead to such a curve we show that suitable preferences can always lead to an ekc while there is no technology that yields an ekc for all types of preferences and we derive a sufficient condition for technology that leads to an ekc for almost all types of preferences our results hold for a model with multiple goods with different pollution intensities and for a production economy with nonconstant relative price of consumption and environmental effort we derive our results without assuming specific functional forms and we encompass several other models as special cases