on the robustness of robustness checks of the environmental kuznets curve hypothesis since its first inception in the debate on the relationship between environment and growth in 1992 the environmental kuznets curve hypothesis ekc hereafter has been subject of continuous and intense scrutiny the most recent line of investigation criticizes the ekc hypothesis on more fundamental grounds in that it stresses the lack of sufficient statistical testing of the empirical relationship and questions the very existence of the notion of ekc attention is in particular drawn on the stationarity properties of the series involved per capita emissions or concentrations and per capita gdp and in case of presence of unit roots on the cointegration property that must be present for the ekc to be a well defined concept only at that point can the researcher ask whether the long run relationship exhibits an inverted u pattern on the basis of panel integration and cointegration tests for sulfur stern 2004 and perman and stern 1999 2003 have presented evidence and forcefully stated that the ekc hypothesis does not exist in this paper we ask whether similar strong conclusions can be arrived at when carrying out tests of system fractional integration and cointegration as an example we use the controversial case of carbon dioxide emissions the results show that more ekcs come back into life relative to traditional integration cointegration tests however we confirm that the ekc hypothesis remains a fragile concept

micro incentives and municipal behavior political decentralization and fiscal federalism in argentina and mexico summary this article analyzes the mixed results of political and fiscal decentralization in latin america by comparing taxing and spending policies in six cities in argentina and mexico consistent with previous studies we find that decentralization has been frustrated by overconcentration of power at the provincial level and large vertical fiscal imbalances though we characterize these as functional elements in a system of redistributive policy making that benefits a wide array of provincial and municipal actors we seek to add a new dimension to the literature by arguing that micro level incentives conditions and circumstances particular to specific places are more important determinants of municipal behavior than macro level structures those policy and institutional changes intended to make officials more responsive to local conditions federalism local elections intergovernmental transfers and own source revenues we conclude that the theory of decentralization relies on a flawed conception of the causal mechanisms that are hypothesized to create responsiveness in local officials

one size fits all towards a differentiated regional innovation policy approach innovation has moved to the foreground in regional policy in the last decade concrete policies were shaped by best practice models derived from high tech areas and well performing regions these are often applied in a similar way across many types of regions here an attempt is made to show that there is no ideal model for innovation policy as innovation activities differ strongly between central peripheral and old industrial areas in this paper we analyse different types of regions with respect to their preconditions for innovation networking and innovation barriers based on this classification different policy options and strategies are developed

interrupted work careers depreciation and restoration of human capital the quantitative effects and even the existence of a human capital depreciation phenomenon have been a subject of controversy in the recent literature prior work however was largely cross sectional and the longitudinal dimension if any was retrospective using longitudinal panel data on married women in nls we have now established that real wages at reentry are indeed lower than at the point of labor force withdrawal and the decline in wages is greater the longer the interruption another striking finding is a relatively rapid growth in wages after the return to work this rapid growth appears to reflect the restoration or repair of previously eroded human capital the phenomenon of depreciation and restoration is also visible in data for immigrants to the united states however while immigrants eventually catch up with and often surpass natives returnees from the nonmarket do not fully restore their earnings potential

industrial pollution in economic development the environmental kuznets curve revisited abstract using new international data this paper tests the environmental kuznets curve ekc hypothesis for industrial water pollution we measure the effect of income growth on three determinants of pollution the share of industry in national output the share of polluting sectors in industrial output and end of pipe eop pollution intensities per unit of output in the polluting sectors we find that the industry share of national output follows a kuznets type trajectory but the other two determinants do not when combined our results imply rejection of the ekc hypothesis for industrial water pollution it rises rapidly through middle income status and remains roughly constant thereafter

interrelationships between income health and the environment extending the environmental kuznets curve hypothesis abstract this paper examines the link between the health indicators and the environmental variables for a cross section of countries widely dispersed on the economic development spectrum while environment and income are seen to have an inverted u shaped relationship environmental kuznets curve ekc hypothesis it is also well established that environment and health are positively related our study focuses on the implications of this for the relationship between health and income in the early phases of income growth the gains in health and the losses in environmental quality could cancel each other out and this challenges the idea that as incomes increase health would always improve to empirically analyse these issues we estimate a two stage least squares model that focuses on the impact of income and the environment on health status with environment being an endogenous variable our results show that the environmental stress variable has a significant negative effect on health status at the same time gross national product gnp levels are shown to vary positively with health status variables we find that the health gains obtained through improved incomes can be negated to a significant extent if the indirect effect of income acting via the environment is ignored research findings in this regard would be a useful policy instrument towards maximising both the environmental and health gains that come with economic growth and development

the toxic intensity of industrial production global patterns trends and trade policy this paper exploits a newly developed data set to investigate recent changes in the international distribution of industrial pollution in particular the authors examine three issues 1 the relationship between the toxic intensity of industrial production and the level of economic development 2 the impact of oecd environmental regulation on global changes in toxic intensity and 3 the relationship between trade policy and the toxic intensity of industrial production in ldc s 10 refs

assimilation and the earnings of young internal migrants this paper investigates if young internal migrants in the united states experience economic assimilation as they adapt to their new residential location using data from the national longitudinal survey of youth the authors examine how the hourly earnings of interstate migrants are affected by the number of years they have spent in their destination state their study indicates that internal migrants initially earn less than natives but that this wage differential disappears within a few years moreover the initial wage disadvantage of internal migrants depends upon the distance moved and economic conditions in the destination labor market copyright 1992 by mit press

between estimates of the emissions income elasticity abstract recent papers by wagner and vollebergh et al point out some fundamental econometric problems with traditional methods of estimating the environmental kuznets curve ekc and propose alternative approaches that avoid these issues wagner notes that traditional methods do not take into account the presence of powers of unit root variables and cross sectional dependence in the data while vollebergh et al point out that the time effects are not uniquely identified in the ekc model the between estimator is a simple estimator that also addresses the concerns of these authors it makes no a priori assumption about the nature of the time effects and is likely to provide consistent estimates of long run relationships in real world data situations i apply several common panel data estimators including the between estimator to oecd and global carbon and sulfur emissions datasets the between estimates of the sulfur income elasticity are 0 732 in the oecd and 1 067 in the global data set and the estimated carbon income elasticity is 1 612 in the oecd and 1 509 globally

livelihoods and poverty the role of migration a critical review of the migration literature this review of the literature concludes that development studies have paid insufficient attention to labour migration and makes a plea to integrate analyses of migration within those of agricultural and rural development it emphasises that population mobility is much more common than is often assumed and that this has been so throughout human history in fact available material suggests that it is as likely that population mobility has decreased as that it has increased a review of empirical studies shows that it may not be possible to generalise about the characteristics of migrants or about the effects of migration on broader development inequality or poverty the review concludes that given the importance of migration for the rural livelihoods of many people policies should be supportive of population mobility and possibilities should be explored to enhance the positive effects of migration

environmental kuznets curves real progress or passing the buck abstract recent research has examined the hypothesis of an environmental kuznets curve ekc the notion that environmental impact increases in the early stages of development followed by declines in the later stages these studies have focused on the relationship between per capita income and a variety of environmental indicators results imply that ekcs may exist for a number of cases however the measures of environmental impact used generally focus on production processes and reflect environmental impacts that are local in nature and for which abatement is relatively inexpensive in terms of monetary costs and or lifestyle changes significantly more consumption based measures such co2 emissions and municipal waste for which impacts are relatively easy to externalize or costly to control show no tendency to decline with increasing per capita income by considering consumption and trade patterns the author re examines the concept of the ekc and proposes the use of alternative consumption based measures of environmental impact the author speculates that what appear to be improvements in environmental quality may in reality be indicators of increased ability of consumers in wealthy nations to distance themselves from the environmental degradation associated with their consumption

climate policy bucket or drainer abstract worldwide industry is responsible for about 40 of greenhouse gas ghg emissions making it an important target for climate policy energy intensive industries may be particularly vulnerable to higher energy costs caused by climate policy if companies cannot offset rising energy costs and would face increased competition from countries without climate policy they may decide to relocate their industrial production to the countries without climate policy the resulting net effect of climate policy on ghg emissions in foreign countries is typically referred to as carbon leakage carbon leakage may lead to higher global ghg emissions due to the use of less advanced technology in less developed countries based on a literature review of climate policy earlier environmental policy and analyses of historical trends this paper assesses the carbon leakage effects of climate policy for energy intensive industries reviews of past trends in production location of energy intensive industries show an increased global production share of non annex 1 countries however from empirical analyses we conclude that the trend is primarily driven by regional demand growth in contrast climate policy models show a strong carbon leakage even though future climate policy may have a more profound impact than environmental policies in the past the modelling results are doubtful leakage generally seems to be overestimated in current models especially as potential positive spillovers are often not included in the models the ambiguity of the empirical analyses and the modelling results warrants further research in the importance of production factors for relocation

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

postponing maternity in ireland as in many other developed countries ireland has experienced a postponement of maternity whilst a number of authors have commented on this trend suggesting greater female participation in the workforce results in delayed maternity to date little research has tested this proposition we develop a model to consider the main trends related to the phenomenon of maternity postponement considering changes in first and later births separately using retrospective life history data developed from the 1994 living in ireland survey we estimate a hazard model to empirically test the relationship between career planning and the timing of first and subsequent births we incorporate a declining marginal return to experience and thereby provide a human capital career planning explanation for maternity postponement the results of our analysis demonstrate that career planning has an impact on the timing of maternity the findings also establish an income effect that influences the timing of first births copyright the author 2010 published by oxford university press on behalf of the cambridge political economy society all rights reserved oxford university press

interstate migration in mexico variations on the todaro theme abstract this study of migration in mexico is based upon a modified todaro approach and utilizes census data in a simultaneous equations model of 13 variables it is unique in several ways a it introduces proxy variables for employment probability and cost of migration that have not heretofore been found in the literature but for which data are often available b it illustrates that in some important cases census data have advantages not available through surveys and c it finds that in some sense land reform in mexico may have operated perversely finally the study opens a new avenue for the study of informal sector growth

identifying reduced form relations with panel data the case of pollution and income abstract in this paper we propose a solution to the non robustness that plagues the estimation of inverted u shaped relationships using panel data such as the relation between pollution and income when dependent and independent variable like pollution and income are both time related separating the effect of the independent variable from time effects brings about a fundamental identification dilemma the imposition of restrictions on the controls might drive the shape of the relationship between the dependent pollution and independent income variables our solution consists of imposing the very weak constraint that arbitrary cross sectional units have the same relationship we apply our methodology to two widely studied cases namely so 2 and co 2 emissions interestingly our estimates are insensitive to the required subjective choices but also strongly differ from the literature so far we find consistent positive income effects for both cases and time effect estimates with a clear u shaped trend for so 2 emissions but only slightly so for co 2 emissions

the explicit economics of knowledge codification and tacitness this paper attempts a greater precision and clarity of understanding concerning the nature and economic significance of knowledge and its variegated forms by presenting the skeptical economist s guide to tacit knowledge it critically reconsiders the ways in which the concepts of tacitness and codification have come to be employed by economists and develops a more coherent re conceptualization of these aspects of knowledge production and distribution activities it seeks also to show that a proposed alternative framework for the study of knowledge codification activities offers a more useful guide for further research directed to informing public policies for science technological innovation and long run economic growth copyright 2000 by oxford university press

an alternative analysis of apparent ekc type transitions abstract the hypothesis of the environmental kuznets curve ekc depends upon the assumption that countries pass through a similar environmental impact trajectory as they experience income growth implying that income levels determine pollution levels the authors present evidence that this is not representative of the way many individual country s pollution emission trajectories evolve and question the emphasis on income determinism by the ekc the study proposes that nonlinear dynamic systems analysis provides a more complete description of individual country pollution trajectories in the case of co 2 emissions the nonlinear time trajectories show abrupt transitions that occur contemporaneously with historical events and over a broad range of incomes

economic growth and emissions reconsidering the empirical basis of environmental kuznets curves abstract recent empirical research indicates that certain types of emissions follow an inverted u or environmental kuznets curve ekc as income grows this regularity has been interpreted as a possible de linking of economic growth and patterns of certain pollutants for developed economies in this paper the empirical basis of this result is investigated by considering some statistical particularities of the various ekc studies performed it is argued that the inverted u relationship between income and emissions estimated from panel data need not hold for specific individual countries over time based on insights from intensity of use analysis in resource economics an alternative growth model is specified and estimated for three types of emissions co2 nox and so2 in four countries netherlands uk usa and western germany it is found that the time patterns of these emissions correlate positively with economic growth and that emission reductions may have been achieved as a result of structural and technological changes in the economy sustainable growth is defined as the rate of economic growth that does not lead to growth in emissions its rate is calculated for each type of emission and country based on estimated parameter values the resulting indicators reflect a balance between the positive influence of growth and negative influence of structural change and technological progress on emission levels

sectoral patterns of technical change towards a taxonomy and a theory abstract the purpose of the paper is to describe and explain sectoral patterns of technical change as revealed by data on about 2000 significant innovations in britain since 1945 most technological knowledge turns out not to be information that is generally applicable and easily reproducible but specific to firms and applications cumulative in development and varied amongst sectors in source and direction innovating firms principally in electronics and chemicals are relatively big and they develop innovations over a wide range of specific product groups within their principal sector but relatively few outside firms principally in mechanical and instrument engineering are relatively small and specialised and they exist in symbiosis with large firms in scale intensive sectors like metal manufacture and vehicles who make a significant contribution to their own process technology in textile firms on the other hand most process innovations come from suppliers these characteristics and variations can be classified in a three part taxonomy based on firms 1 supplier dominated 2 production intensive 3 science based they can be explained by sources of technology requirements of users and possibilities for appropriation this explanation has implications for our understanding of the sources and directions of technical change firms diversification behaviour the dynamic relationship between technology and industrial structure and the formation of technological skills and advantages at the level of the firm the region and the country

who moves a logit model analysis of inter provincial migration in canada this paper addresses the topic of inter provincial migration in terms of the basic question who moves panel logit models of the probability that an individual changes his or her province of residence from one year to the next over the 1982 1995 period are estimated using tax based longitudinal data it is found that moving is i inversely related to the home province s population size presumably reflecting local economic conditions and labour market scale effects while language also plays an important role ii more common among residents of smaller cities towns and especially rural areas than those in larger cities iii negatively related to age marriage and the presence of children for both men and women iv positively related to the provincial unemployment rate the individuals receipt of unemployment insurance except entry men having no market income except for entry men and entry women and the receipt of social assistance especially for men v slightly positively related

estimation of short run and long run elasticities of energy demand from panel data using shrinkage estimators this article discusses the problem of obtaining short run and long run elasticities of energy demand for each of 49 states in the united states using data for 21 years estimation using the time series data by each state gave several wrong signs for the coefficients estimation using pooled data was not valid because the hypothesis of homogeneity of the coefficients was rejected shrinkage estimators gave more reasonable results the article presents in a unified framework the classical empirical bayes and bayes approaches for deriving these estimators

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

the nexus of electricity consumption economic growth and co2 emissions in the brics countries abstract this study reexamines the causal link between electricity consumption economic growth and co 2 emissions in the brics countries i e brazil russia india china and south africa for the period 1990 2010 using panel causality analysis accounting for dependency and heterogeneity across countries regarding the electricity gdp nexus the empirical results support evidence on the feedback hypothesis for russia and the conservation hypothesis for south africa however a neutrality hypothesis holds for brazil india and china indicating neither electricity consumption nor economic growth is sensitive to each other in these three countries regarding the gdp co 2 emissions nexus a feedback hypothesis for russia a one way granger causality running from gdp to co 2 emissions in south africa and reverse relationship from co 2 emissions to gdp in brazil is found there is no evidence of granger causality between gdp and co 2 emissions in india and china furthermore electricity consumption is found to granger cause co 2 emissions in india while there is no granger causality between electricity consumption and co 2 emissions in brazil russia china and south africa therefore the differing results for the brics countries imply that policies cannot be uniformly implemented as they will have different effects in each of the brics countries under study

what exactly are technological regimes intra industry heterogeneity in the organization of innovation activities this empirical study analyzes the patterns of innovation within and across industries using firm level survey data from finland and denmark the theoretical starting point is evolutionary theory with its premise that firms in different technological regimes pursue different paths to innovation similar modes of behaviour are found in the two datasets and they closely correspond to those found in earlier studies contrary to prevailing assumptions however the results show that industries are not at all uniform in terms of how firms innovate in almost all four or five digit nace industries three or more different modes of innovation can be identified this suggests that firms strategic differentiation or local search activities overcome pressures in the technological environment towards homogenous behaviour at least in the short term

rationality of migration the paradigm of a rational individual acting on the earnings enhancing benefits of migration is subjected to statistical scrutiny using data from turkey results with robust selectivity correction support the rationality hypothesis both migrants and nonmigrants chose the option in which they had comparative advantage however the estimated gain from moving is negative for a substantial portion of migrants whereas a minority realize very high returns this suggests that migration is a lottery individuals are willing to invest in a proposition that has a high probability of yielding negative returns because of the potential for a very large payoff

type of employer and fertility of working women does working in the public sector or in a large private firm matter this work investigates how fertility rates of working women have been influenced by employer characteristics public versus private sector and small versus large firms and features of the employment contracts using a representative sample of italian working women in the last 30 years of the twentieth century in particular we find that women working in the public sector have a higher probability of having a child during a working spell than women working in the private sector furthermore women working in large private sector firms who enjoy stronger employment protection have a higher probability of having a child than those working in smaller firms in turn more stable contracts also increase the likelihood of having a child during a working spell results are robust to controlling for individual unobserved heterogeneity and for the possible endogeneity of working in the public sector copyright oxford university press

convergence of per capita carbon dioxide emissions in the eu legend or reality abstract designing appropriate environmental and energy policies in order to meet the kyoto protocol s carbon dioxide co 2 reduction targets in the european union eu requires a detailed examination and thorough understanding of co 2 emission trends across the eu member states this paper investigates whether co 2 emissions have converged across 22 european countries over the 1971 to 2006 period the bayesian shrinkage estimation method is employed to do this work and the results reveal the following first the hypothesis of absolute convergence in per capita co 2 emissions is supported and a slight upward convergence is observed second the fact that countries differ considerably in both their speed of convergence and volatility in emissions makes it possible to identify different groups of countries third the results with respect to convergence do not vary much once the share of industry in gdp is accounted for in a conditional convergence analysis however a decreasing share of industry in gdp seems to contribute to a decline in per capita emissions these findings may carry important implications for both national and eu environmental policies

economic growth and environmental degradation the environmental kuznets curve and sustainable development abstract in this paper we critically examine the concept of the environmental kuznets curve ekc it proposes that there is an inverted u shape relation between environmental degradation and income per capita so that eventually growth reduces the environmental impact of economic activity the concept is dependent on a model of the economy in which there is no feedback from the quality of the environment to production possibilities and in which trade has a neutral effect on environmental degradation the actual violation of these assumptions gives rise to fundamental problems in estimating the parameters of an ekc the paper identifies other econometric problems with estimates of the ekc and reviews a number of empirical studies the inference from some such ekc estimates that further development will reduce environmental degradation is dependent on the assumption that world per capita income is normally distributed when in fact median income is far below mean income we carry out simulations combining ekc estimates from the literature with world bank forecasts for economic growth for individual countries aggregating over countries to derive the global impact within the horizon of the bank s forecast 2025 global emissions of so 2 continue to increase forest loss stabilizes before the end of the period but tropical deforestation continues at a constant rate throughout the period

the determinants of atmospheric so2 concentrations reconsidering the environmental kuznets curve this analysis explores the effects of income and the spatial intensity of economic activity on the atmospheric concentration of sulfur dioxide the results indicate that there is a u shaped relation between income and atmospheric concentration of so2 and an inverted u shaped relation between the spatial intensity of economic activity and so2 concentrations these results suggest that the spatial intensity of economic activity rather than income provides the impetus for policies and technologies that reduce so2 emissions based on this result the atmospheric concentration of so2 in developing nations may decline faster than indicated by previous analyses the potential for this decline depends on the rate at which income grows relative to population the trade off between the effects of income gains and the spatial intensity of economic activity on the atmospheric concentration of so2 is consistent with the notion that some environmental problems can be ameliorated by slowing population growth and increasing income levels

environmental kuznets curve for co2 in canada abstract according to the environmental kuznets curve hypothesis the relationship between per capita gdp and per capita pollutant emissions has an inverted u shape this implies that past a certain point economic growth may actually be profitable for environmental quality most studies on this subject are based on estimating fully parametric quadratic or cubic regression models while this is not technically wrong such an approach somewhat lacks flexibility since it may fail to detect the true shape of the relationship if it happens not to be of the specified form we use semiparametric and flexible nonlinear parametric modeling methods in an attempt to provide more robust inferences we find little evidence in favour of the environmental kuznets curve hypothesis our main results could be interpreted as indicating that the oil shock of the 1970s has had an important impact on progress towards less polluting technology and production

a nested logit migration model with selectivity in this paper we specify a multiple choice migration model with selectivity we estimate this model using observations on individuals drawn from the 1971 census of venezuela there are two main innovations in this paper we apply a correction for the presence of selectivity in wage equations in the context of a multiple choice migration model and we apply a less restrictive technique for modelling multiple discrete choices than in previous studies we study the choices of individuals among 23 states of venezuela each individual is observed to have chosen one state so one wage is observable per person our hypothesis is that individuals choose where to locate on the basis of an evaluation of costs and benefits associated with choosing each state we measure the benefits associated with choosing a given state by means of the wage a person could earn in this state since we observe only one wage for each person we have to impute the unobserved wages for the states this person did not choose in order to study the role of wages in migration however it is possible that unobserved factors which affect both an individual s choice of location and his wages may result in sample selection bias if we try to estimate state specific wage equations by ols on the basis of the self selected samples we apply an estimator proposed by lee 1983 to estimate state specific wage equations free from sample selection bias the wage equations permit us to investigate whether individuals who choose particular states earn different wages from observationally identical individuals drawn from the population at random in the context of a developing country where internal migration flows are large evidence on the selectivity of migration will enhance our understanding of an important labor market adjustment mechanism evidence that people who choose particular locations earn more in those locations than would observationally identical individuals drawn at random from the population positive selection will suggest that migration decisions are made according to the principle of comparative advantage in modelling the choice of location we test whether subsets of states are more highly similar to each other than to other states unobserved similarities between states may arise because of similar amenities or economic conditions which are not otherwise explicitly controlled for in the model we implement the

internal and international migration in mexico 1995 2000 using micro data from mexico and us 2000 population censuses and following a multi choice variant of roy s 1951 model this article pools into one model the determinants of internal and international migration in mexico while paying explicit attention to the potential problem of self selection the results reveal that ignoring multiple destinations in the migration decision might lead to erroneous inferences about the determinants of migration and the type of selection after controlling for wage differences the results suggest that single adult men with low schooling levels tend to migrate to the us while married women and men with higher levels of schooling tend to migrate within mexico we also found that there are strong differences between domestic and international social networks

migration networks and microenterprises in mexico are migration networks associated with lower capital costs or the alleviation of capital constraints we examine these questions with data measuring access to remittance flows among small scale entrepreneurs in mexico using a survey of more than 6000 self employed workers and small firm owners located in 44 urban areas of mexico we estimate the impact of attachment to migration networks on the level of capital investment the capital output ratio sales and profits of microenterprises the impact is identified from the geographic pattern of migration from mexico driven by the completion of rail lines in the early 1900s for the full sample of firms we find that migration is associated with higher investment levels and higher profits but not higher sales the strongest effects on investment are in the categories of automobiles tools and inventories when the sample is limited to firms in high capital sectors investment sales and profits all increase with attachment to the migration networks suggesting that attachment to the migration network alleviates capital constraints in those sectors

the environmental kuznets curve semi parametrically revisited this paper re examines the existence of an environmental kuznets curve ekc across countries using a semi parametric regression estimator which places no restrictions on the functional form our results using cross country panel data on sulfur and carbon dioxide strongly suggest that the relationship between wealth and environmental degradation is not bell shaped as suggested by an ekc rather that there is a positive link for the very poorest countries and no clear relationship for richer countries

marital status and earnings of young men a model with endogenous selection it is a matter of course in applied labor economics to presume that marital status is a predetermined contributor to earnings among young males we find no evidence to support that proposition we estimate a model of earnings determination that permits endogenous selection of marital status our estimates are based on a sample of young employed males from the michigan panel survey of income dynamics they indicate that marital status viewed in this manner does not significantly shift the mean earnings profile our sensitivity tests indicate that this conclusion is robust with respect to a variety of alternative specifications excerpt

the nexus between carbon emissions energy consumption and economic growth in middle east countries a panel data analysis abstract the environmental kuznets curve ekc hypothesis assumes that there is an inverted u shaped relationship between environmental degradation and income per capita in other words as a country grows it is assumed that its environmental quality improves in this study we aim to test the ekc hypothesis for 12 middle east countries during the period 1990 2008 by employing recently developed panel data methods our results provide evidence contrary to the ekc hypothesis we found evidence favorable to the u shaped ekc for 5 middle east countries whereas an inverted u shaped curve was identified for only 3 middle east countries furthermore there appear to be no causal links between income and co 2 emissions for the other 4 countries regarding the direction of causality there appears to be a unidirectional causality from economic growth to energy consumption in the short run in the long run however the unidirectional causality chain runs from energy consumption and economic growth to co 2 emissions we also suggest some crucial policy implications depending on these results

migration and the urban to rural earnings difference a sample selection approach in particular i conjecture that in many parts of rural africa a self selection mechanism may occur that sorts migratory and nonmigratory workers in a manner consistent with the notion that those workers who are most likely to benefit from migration do so and workers least likely to benefit from migration do not in other words individuals sort themselves into migratory and nonmigratory workers given their characteristics for instance rural workers with relatively more human capital skills are most likely to migrate because the discrepancy is larger between earnings from rural unskilled jobs that underutilize their skills and earnings from skilled jobs in urban areas that more fully realize their potential given their characteristics therefore participation in the migratory labor stream is strongly assumed to be influenced by the workers anticipated earnings as a migrant versus his or her anticipated earnings from working in the rural area as a nonmigrant it is thus conceivable that the urban to rural earnings difference would be positive for workers with relatively greater skills and that their incidence of migration may be higher this study tests this hypothesis excerpt

the heterogeneity of carbon kuznets curves for advanced countries comparing homogeneous heterogeneous and shrinkage bayesian estimators we investigate carbon kuznets curves ckc relationships for advanced countries grouped in policy relevant groups north america and oceania south europe north europe by means of various homogeneous heterogeneous and shrinkage bayesian panel estimators we try to provide an answer to the question how sensitive are the ckc estimates to changes in the level of parameters heterogeneity we do find that in coherence with their policy and economic commitment to carbon reductions and environmental market based instruments implementation bell shapes are present only for northern eu which leads the group of advanced countries the other two lag behind we show for the first time that ckc shapes are present if we net out europe of the southern and less developed countries this is coherent with the kuznets paradigm the negative side of the tale is that they characterize a bunch of few countries other advanced countries lag behind and are far from reaching a ckc dynamics heterogeneous and bayesian

trade the pollution haven hypothesis and the environmental kuznets curve examining the linkages abstract this paper examines the extent to which the ekc inverted u relationship can be explained by trade and specifically the migration or displacement of dirty industries from the developed regions to the developing regions the pollution haven hypothesis phh using detailed data on north south trade flows for pollution intensive products the evidence for the phh is assessed emissions of 10 air and water pollutants are then estimated controlling for trade openness structural change and dirty north south trade flows evidence of pollution haven effects is found although such effects do not appear to be widespread and appear to be relatively small compared to the roles played other explanatory variables

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

a fractional cointegration analysis of purchasing power parity a generalized notion of cointegration called fractional cointegration is introduced to examine the long run purchasing power parity ppp hypothesis by allowing deviations from equilibrium to follow a fractionally integrated process the fractional cointegration analysis can capture a wider range of mean reversion behavior than standard cointegration analyses this gain is flexibility in modeling subtle mean reverting dynamics is found to be important for a proper evaluation of long run ppp empirical results based on historical data for the 1914 1989 period show that ppp reversion exists and can be characterized by a fractionally integrated process in three out of five countries studied the results support ppp as a long run phenomenon though significant short run deviations from ppp can exist

carbon intensity and economic development 1962 1991 a brief exploration of the environmental kuznets curve the relationship between national carbon dioxide emissions intensity co2 emitted per unit of gross domestic product and level of economic development has changed from essentially linear in 1962 to strongly curvilinear in 1991 the inverted u curve reached statistical significance briefly in the early 1970s and increasingly since 1982 this is the result not of groups of countries passing through stages of development but of efficiency improvements in a small number of wealthy countries combined with worse performance in poor and middle income countries the curvilinear relation is deepening and is likely to persist due to constraints on poorer countries in the world economy

economic growth trade and energy implications for the environmental kuznets curve abstract the environmental kuznets curve ekc hypothesis asserts that pollution follows an inverted u path with respect to economic growth the ekc has been explained in terms of structural changes in the composition of economic output and increased environmental regulation at higher income levels while some authors have incorporated the impact of trade policy orientation on the ekc the impact of the actual movement between countries of goods that embody pollution has not been considered this paper attempts to econometrically quantify the effect using pooled cross country and time series data the ekc hypothesis is examined with respect to commercial energy consumption the source of many serious environmental problems it was found that while both industrializing and industrialized countries have added to their energy requirements by exporting manufactured goods the growth has been substantially higher in the former at the same time industrialized countries have been able to reduce their energy requirements by importing manufactured goods exports of manufactured goods by industrialized countries has thus been an important factor in generating the upward sloping portion of the ekc and imports by industrialized countries have contributed to the downward slope

technology systems and technology policy in an evolutionary framework the central purpose of this paper is to outline an evolutionary theory of technology policy and to connect it with the emerging literature on national systems of innovation any understanding of technology policy must be based on a clear understanding of the nature of technology and the important differences between science and technology technology can be treated in terms of knowledge skills and artifacts and in each case there are different variety generating mechanisms different selection processes and different institutional structures for policy purposes the degree of connection between these different dimensions of technology is at the core of technology policy c 1995 academic press inc copyright 1995 by oxford university press

mobility and the return to education testing a roy model with multiple markets self selected migration presents one potential explanation for why observed returns to a college education in local labor markets vary widely even though u s workers are highly mobile to assess the impact of self selection on estimated returns this paper first develops a roy model of mobility and earnings where workers choose in which of the 50 states plus the district of columbia to live and work available estimation methods are either infeasible for a selection model with so many alternatives or place potentially severe restrictions on earnings and the selection process this paper develops an alternative econometric methodology that combines lee s 1983 parametric maximum order statistic approach to reduce the dimensionality of the error terms with more recent work on semiparametric estimation of selection models e g ahn and powell 1993 the resulting semiparametric correction is easy to implement and can be adapted to a variety of other polychotomous choice problems the empirical work which uses 1990 u s census data confirms the role of comparative advantage in mobility decisions the results suggest that self selection of higher educated individuals to states with higher returns to education generally leads to upward biases in ols estimates of the returns to education in state specific labor markets while the estimated returns to a college education are significantly biased correcting for the bias does not narrow the range of returns across states consistent with the finding that the corrected return to a college education differs across the u s the relative state to state migration flows of college versus high school educated individuals respond strongly to differences in the return to education and amenities across states

information access income distribution and the environmental kuznets curve abstract recent empirical studies have tested the hypothesis of an environmental kuznets curve ekc focusing primarily on the relationship between per capita income and certain types of pollutant emissions given the stock nature of many pollution problems emissions only partially account for the environmental impacts moreover almost all of the studies have given consideration to little more than income levels as explanatory variables this paper empirically tests the hypothesis of the ekc existence for a stock sensitive indicator that is the percentage of protected area pa within national territory it does theorize that economic growth is a necessary condition in order to better address environmental issues but it also stresses that other variables income distribution education information accessibility may play a fundamental role in determining environmental quality contrary to other studies that mainly focus on the calculation of the income level corresponding to the transition point this paper is more concerned with the calculation of environmental quality corresponding to that transition point that is the minimum level of environmental quality that a country is willing to accept this paper highlights the idea that if the transition point is determined primarily by income level social policies determine the level of environmental quality corresponding to that point

transitional impacts of environmental policy in an endogenous growth model to explore the link between a tighter environmental policy and economic growth the authors employ an endogenous growth model with endogenous technological progress in abatement technologies the environment which is modelled as a renewable resource acts both as a public consumption good and as a public input into production the entire transition towards a new balanced growth path after a tightening of environmental policy is computed analytically the authors find sharp contrasts between short run and long run effects whereas the level and the growth rate of output may decline in the short run income growth may improve in the long run copyright 1996 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

estimating country specific environmental kuznets curves from panel data a bayesian shrinkage approach designing an efficient global climate policy turns out to be a difficult yet crucial task since there are noteworthy cross country differences in energy and carbon intensities in this article the environmental kuznets curve ekc hypothesis is tested for carbon dioxide co2 emissions and as a modelling technique the iterative bayesian shrinkage procedure is employed to handle the cross country differences the results suggest that first the ekc hypothesis is rejected for 47 out of the 51 countries considered when the heterogeneity in countries energy efficiencies and cross country differences in the co2 emissions trajectories are accounted for second a classification of the results with respect to the development levels of the countries concerned reveals that the emergence of an overall inverted u shaped curve is due to the fact that in high income countries increase in gross domestic product gdp decreases emissions while in low income countries emissions and gdp are positively correlated

complementarities between obstacles to innovation evidence from france abstract this paper investigates obstacles to innovation faced by french manufacturing firms using cis2 data we distinguish between obstacles in postponed projects and obstacles in abandoned projects first we highlight the most important barriers to innovation faced by firms and find that lack of skilled personnel is one of these second based on descriptive analysis correspondence analysis and multivariate probit models we explore factors explaining the perception of obstacles and study complementarities between those obstacles we show that while adopting a package of policies increases the pace of innovation a more targeted choice among policies is needed to encourage firms to persevere in their innovative efforts

measuring systemic problems in national innovation systems an application to thailand the paper contributes to research on innovation systems in general and in particular to the current debate on rationales for innovation policy by providing a framework to identify systemic problems in a given system of innovation and test the framework empirically the data were drawn from the thai community innovation survey in the period after which a major change in the country s innovation system policy had been initiated by hierarchical factor analysis systemic problems are identified and grouped into four components institution network science and technology infrastructure and other support services the analysis allows researchers to investigate the mismatch between policies and problems and identify policy gaps c 2012 elsevier b v all rights reserved less

internal migration and urban employment reply despite the diversity and intensity of michael todaro s comment 1986 the essence of controversy reduces to differences in the respective views of the urban subsistence sector each view in turn depends upon a distinctive viewpoint observing from the viewpoint of the bureaucrat and other elite to whom he defers in his comment todaro sees the large cityward flow of third world humanity as a menace destroying urban amenities todaro s focus being the modern sector his model only incorporates an urban subsistence sector indirectly and then only as a way station on the route to modern sector employment his assumption is that every potential migrant has modern sector employment as an explicit goal conceptually he leaves no room for the uneducated rural persons whose aspirations are keyed to the modest employments of the urban subsistence sector we on the other hand look from below from the subsistence sector from there we see both rural and urban welfare gains from observed spatial movement of labor we grant that unpleasant externalities may be involved especially from the point of view of a discomfitted elite however those possible externalities should be studied in their own right and have no place in a debate between competing explanations of migration 2 the present debate therefore comes down to a straightforward empirical question if in fact there are persons who move to the city with the intent of taking up permanent employment in the urban subsistence sector then their decisions cannot be explained by todaro if they are few in number the theorist may assume them away if their numbers are significant however migration flows must be viewed as dual in nature and an alternative explanation for the subsistence portion is required todaro s crucial point is that the colesanders theory requires them to make an artificial separation of migration flows into those who go to the modern sector and those who go to and remain in the subsistence sector this argument is effectively countered we believe by our crucial point that todaro s view of an undifferentiated flow carries with it the inappropriate assumption that all migrants deem themselves able to enter into modern sector employment 3

self selection and the earnings of immigrants this paper analyzes the way in which the earnings of the immigrant population may be expected to differ from the earnings of the native population because of the endogeneity of the decision to migrate the empirical study shows that differences in the u s earnings of immigrants with the same measured skills but from different home countries are attributable to variations in political and economic conditions in the countries of origin at the time of migration excerpt

migration self selection and earnings in philippine rural communities abstract estimated returns to schooling investments can be misleading if migration causes significant shifts in population distribution across time data gathered in rural philippine communities show that the more educated and experienced individuals are more likely to outmigrate causing a sample selection bias in the estimation of wage equations the observed wages were then lower than the conditional population mean of an entire cohort residing originally in the area controlling for self selection the wage returns to schooling and experience were higher finally the sample selectivity variable accounts substantially for the difference in the wages of men and women

instability in rural urban migration following decades of large scale rural urban migration in developing countries the authors note the recent growth in reverse migration or migration from urban centers to suburban or rural areas which suggests that the labor market adjustment process may be unstable it is our purpose here to investigate the question of stability using some recent developments in nonlinear dynamic analysis and to do so within a framework which closely resembles the original harris todaro model we find that instability is indeed a possibility and that regular or irregular nonperiodic fluctuations can be propagated even in the absence of any exogenous shocks the source of these results is the lag in adjustment on labour markets combined with the nonlinearity of the labour supply function excerpt

searching for a kuznets curve in environmental efficiency using kernel estimation abstract the paper constructs environmental efficiency indexes for a sample consisting of high and low income countries using nonparametric production frontier techniques and then establishes an environmental kuznets relationship for environmental efficiency by nadaraya watson kernel estimation methodology

innovation systems and inertia in r d location norwegian firms and the role of systemic lock in abstract this paper seeks to enquire why firms ceteris paribus tend to concentrate their r d activities at home using a systems of innovation si approach we argue that r d inertia is associated with structural inertia and resultant systemic lock in interaction within an si is a self reinforcing mechanism which may or may not lead to ex post efficiency lock in can be efficient when technologies and institutions maintain the competitiveness of firms on the other hand radical innovations or technological discontinuities may require new institutions and resources but systemic lock in may prevent rapid reaction firms can use a voice strategy by intervening to modify the appropriate institutions in the existing si or an exit strategy by seeking alternative si which more closely fit their needs in the case of norway two groups of firms exist group a benefit from a systemic lock in these are large firms in traditional sectors which are highly embedded and around whom the norwegian si has been built these firms engage in voice and loyalty group b are in science based sectors for whom lock in results in inefficiencies and use exit slowly expanding r d abroad to seek competences in technologies not available domestically

skilled unskilled wage inequality and urban unemployment i introduction an extensive body of literature has looked at possible effects of trade liberalization on the labor market in the north the effects on the labor market in the south have not drawn as much attention conventional wisdom associated with the stolper samuelson theorem predicts a gradual reduction of skilled unskilled wage inequality in the south however recent studies on latin american countries exhibit conflicting patterns wood 1997 summarizes the empirical findings citing a series of articles by robbins 1995a 1995b 1996a 1996b that convincingly demonstrate that latin america has experienced an increasing wage gap between the skilled and the unskilled following a more open trade and investment regime while globalization induced changes in production patterns and the consequent increase in the demand for skilled labor relative to unskilled labor has often been cited as the root cause of wage inequality there has been no general agreement over the possible source of such increased demand for skilled labor the debate among economists on this has followed two broad paths one relying on technological changes and the other on trade and investment while technological change may have played a key role in the widening wage gap in the industrialized countries there is strong evidence robbins 1994a 1994b 1995a 1995b 1996a 1996b robbins and zveglich 1995 wood 1997 indicating the dominant influence of trade and investment on wage inequality in the developing economies the implications of a more open trade and investment regime need to be analyzed in terms of frameworks that explicitly take into account the structural features of labor markets in the south one of the key structural differences between the north and the south is that the south experiences a pronounced rural urban migration in the presence of urban unemployment basu 1997 ray 1998 the goal of our paper was to capture this feature within the structure of a simple general equilibrium model in an effort to understand the effect of fragmentation on the skilled unskilled wage differential and employment in the south the rest of the paper is organized as follows the next section places this paper in the context of the relevant literature section iii describes the general equilibrium model with the possibility of fragmentation and unemployment section iv compares and contrasts the impact of trade and endowment on the skilled unskilled wage gap and employment with and without fragmentation section v concludes ii context the motivation of this paper stems from our view that the southern experience does not necessarily contradict conventional wisdom as has been claimed in wood 1997 but points to the need for parsimonious yet meaningful modifications of the structure of general equilibrium models from which the wisdom is derived to properly reflect the salient structural features of the south on the one hand production fragmentation has become an important facet of globalization in modern times 1 sharp declines in transportation and communication costs have encouraged this process of slicing the value chain that is evident in international trade data this has been sustained by various regional integration agreements that have reduced the barriers to international trade and investment as well as important technical innovations in telecommunications and information technology that have facilitated the coordination of international production networks this advanced stage in the international division of the chain of production has brought a fundamental change in the nature of international trade as goods increasingly cross multiple national borders while they are in process several authors such as jones kierzkowski and lurong 2005 wan 2005 long 2005 jones and kierzkowski 1998 jones and marjit 2001 arndt 1998 feenstra 1998 harris 1998 hummels rapoport and yi 1998 feenstra and hanson 1996b and dixit and grossman 1982 have analyzed the role of fragmentation in world trade

cointegration fractional cointegration and exchange rate dynamics multivariate tests due to johansen 1988 1991 as implemented by baillie and bollerslev 1989a and diebold gardeazabal and yilmaz 1994 reveal mixed evidence on whether a group of exchange rates are cointegrated further analysis of the deviations from the cointegrating relationship suggests that it possesses long memory and may possibly be well described as a fractionally integrated process hence the influence of shocks to the equilibrium exchange rates may only vanish at very long horizons in the article by baillie and bollerslev 1989a it is argued that seven different nominal spot and forward exchange rates all contain unit roots in their univariate time series representations at the same time however the spot exchange rates appear to be tied together in the long run through a cointegration type relationship the latter finding of baillie and bollerslev has attracted particular interest and several studies such as those by hakkio and rush 1991 and sephton and larsen 1991 have already addressed this issue using the same data as the baillie and bollerslev article sephton and larsen 1991 describe the evidence for the presence of cointegration as being fragile and note that mixed conclusions are reached by truncating the baillie and bollerslev sample at different points in time diebold gardeazabal and yilmaz 1994 henceforth diebold et al provide interesting evidence that application of the johansen 1988 1991 tests with and without an intercept will result in different inferences on the baillie and bollerslev data set furthermore diebold et al carry out an ex ante forecasting experiment and find that the addition of an error correction term to the martingale model as implied by the standard cointegration paradigm fails to reduce the prediction mean square error when compared to a simple martingale model this therefore leads diebold et al to conclude that there exists substantial uncertainty regarding the existence of cointegration relationships among nominal dollar exchange rates this article provides some additional evidence on the existence of such a long run relationship among the same seven nominal spot exchange rates after further analysis it appears that a form of cointegration does exist between the exchange rates so that they do not drift apart in the long run we argue that this form of cointegration is

reassessing the environmental kuznets curve for co2 emissions a robustness exercise the number of studies seeking to empirically characterize the reduced form relationship between a country economic growth and the quantity of pollutants produced in the process has recently increased significantly in several cases researchers have found evidence pointing to an inverted u benvironmental kuznetsq curve in the case of co2 however the evidence is at best mixed in this paper we reconsider that evidence by assessing how robust it is when the analysis is conducted in a different parametric setup and when using alternative emissions data from the international energy agency relative to the literature our contribution can be viewed as a robustness exercise in these two respects the econometric results lead to two conclusions firstly published evidence on the ekc does not appear to depend upon the source of the data at least as far as carbon dioxide is concerned secondly when an alternative functional form is employed there is evidence of an inverted u pattern for the group of oecd countries with reasonable turning point regardless of the data set employed not so for non oecd countries as the ekc is basically increasing slowly concave according to the iea data and more bellshaped in the case of cdiac data d 2005 elsevier b v all rights reserved

pooled mean group estimation of an environmental kuznets curve for co2 abstract we apply the pooled mean group estimator to test for the existence of an environmental kuznets curve for co2 in 22 oecd countries this approach allows for more flexible assumptions in a panel data framework the period goes from 1975 to 1998

income inequality and pollution a reassessment of the environmental kuznets curve abstract improvements in some measures of air and water quality can accompany rising per capita income as illustrated by the so called environmental kuznets curve for pollution variables which show such a relationship we hypothesize that a more equitable distribution of power contributes to these outcomes by enhancing the influence on policy of those who bear the costs of pollution relative to the influence of those who benefit from pollution generating activities an empirical analysis of international variations in seven indicators of air and water quality supports this hypothesis literacy political rights and civil liberties are found to have particularly strong effects on environmental quality in low income countries

evolutionary economics and technology policy in this brief paper i propose to explore the economics of technology policy from an evolutionary perspective as with any evolutionary argument the central concern is with the mechanisms of economic change in this case in relation to the development of new technologies and patterns of organisation and their spread into the wider economic system in this sense we build upon one of the major stylized facts of modern growth structural change at all levels from the microeconomic to the macroeconomic to any observer of the policy making process let alone a practitioner the contrast between the theory which underpins policy and the implementation of policy will seem acute as nelson and winter i982 have rightly insisted research into policy is shaped by policy questions not by an agenda relating to how economic theory can be developed to deal with innovation setting priorities designing instruments and evaluating outcomes do not link easily with the general ideas dealt with below among the general points we will stress two will be of critical importance first that the innovation activities of firms involve a wider range of other institutions supplying the knowledge and skills which underpin the efforts of individual firms we term this the systems perspective on innovation nelson i993 secondly it is not helpful to treat innovation and the diffusion of innovation as separate categories in fact they are inseparable with feedback from diffusion being one of the critical elements shaping how a technology is developed we begin with a brief review of the familiar market failure perspective on policy and build from this into a brief overview of the evolutionary approach the paper concludes with an outline of the systems perspective on technology policy it is taken as read that virtually any economic policy can have implications in principle for the process of innovation however we treat technology policy in a narrow sense even though it spills over into questions of education policy science policy and competition policy

a consumption based approach to environmental kuznets curves using the ecological footprint indicator recent research suggests that consumption based measures offer an insightful perspective on the debate on the relationship between economic growth and the environment in this article we deepen the

structural breaks and fractional integration in the us output and unemployment rate abstract in this article we examine the presence of structural breaks in the us output and unemployment rate by means of using fractionally integrated techniques the results based on robinson s journal of the american statistical association 89 1994 1420 tests indicate that for unemployment the inclusion of breaks does not affect to the degree of integration of the series while for the gnp we observe a reduction in its order of integration of about 0 25 when a break due to the oil price crisis is taken into account

a panel data heterogeneous bayesian estimation of environmental kuznets curves for co2 emissions this article investigates the environmental kuznets curves ekc for co2 emissions in a panel of 109 countries during the period 1959 to 2001 the length of the series makes the application of a heterogeneous estimator suitable from an econometric point of view the results based on the hierarchical bayes estimator show that different ekc dynamics are associated with the different sub samples of countries considered on average more industrialized countries show evidence of ekc in quadratic specifications which nevertheless are probably evolving into an n shape based on their cubic specification nevertheless it is worth noting that the eu and not the umbrella group led by us has been driving currently observed ekc like shapes the latter is associated to monotonic income co2 dynamics the eu shows a clear ekc shape evidence for less developed countries consistently shows that co2 emissions rise positively with income though there are some signs of an ekc analyses of future performance neverthe

a climate change policy induced shift from innovations in carbon energy production to carbon energy savings abstract we develop an endogenous growth model with capital labor and carbon energy as production factors and three technology variables that measure accumulated innovations for carbon energy production carbon energy savings and neutral growth all markets are complete and perfect except for research for which we assume that the marginal social benefits exceed the marginal private benefits by factor four the model constants are calibrated so that the model reproduces the relevant global trends over the 1970 2000 period the model contains a simple climate module and is used to assess the impact of induced technological change itc for a policy that aims at a maximum level of atmospheric co2 concentration 450 ppmv itc is shown to reduce the required carbon tax by more than a factor 2 and to reduce costs of such a policy by half when we do not constrain aggregate r d expenditures to benchmark levels costs are further reduced numerical simulations show that knowledge accumulation shifts from energy production to energy saving technology we discuss reasons for differences between our results and earlier results reported in the literature

international migration self selection and the distribution of wages evidence from mexico and the united states we use the 1990 and 2000 mexican and u s population censuses to test borjas s negative selection hypothesis that the less skilled are those most likely to migrate from countries with high skill premia earnings inequality to countries with low skill premia earnings inequality we find that mexican immigrants in the united states are more educated than nonmigrants in mexico and were mexican immigrants to be paid according to current skill prices in mexico they would be concentrated in the middle of mexico s wage distribution these results are inconsistent with the negative selection hypothesis and instead suggest that there is intermediate selection of immigrants from mexico