can falling supply explain the rising return to college for younger men a cohort based analysis although the college high school wage gap for younger u s men has doubled over the past 30 years the gap for older men has remained nearly constant in the united kingdom and canada the college high school wage gap also increased for younger relative to older men using a model with imperfect substitution between similarly educated workers in different age groups we argue that these shifts reflect changes in the relative supply of highly educated workers across age groups the driving force behind these changes is the slowdown in the rate of growth of educational attainment that began with cohorts born in the early 1950s in all three countries

social class family background and intergenerational mobility abstract this research examines the various approaches taken by economists and sociologists for analyzing intergenerational mobility social mobility models based on social classes arising from an occupational classification scheme are analysed a test for the statistical validity of classification schemes is proposed and tested using danish sample survey data that was first collected in 1976 and augmented in 2000 this is referred to as a homogeneity test and is a likelihood ratio test of a set of linear restrictions which define social classes for denmark it is shown that this test fails for an erikson goldthorpe classification system raising doubts about the statistical validity of occupational classification systems in general we also estimate regression models of occupational earnings household earnings and educational attainment using family background variables as covariates controlling for unobservables measurement error and simultaneous equation bias in these models homogeneity tests are also rejected we conclude from these results that the individual s family background has a small but significant impact on lifetime chances which is not captured by the erikson goldthorpe classification scheme

a note on merton s optimum consumption and portfolio rules in a continuous time model in the paper optimum consumption and portfolio rules in a continuous time model by r c merton j econ theory 3 1971 373 413 solutions obtained in cases when marginal utility at zero consumption is finite are not feasible while they do satisfy the hamilton jacobi bellman equations they do not represent appropriate value functions because the boundary behavior near zero wealth is not satisfactorily dealt with in this note we specify the boundary behavior and characterize optimal solutions journal of economic literature classification numbers 022 213

changes in returns to education in latin america the role of demand and supply of skills using micro data for the urban areas of argentina brazil chile colombia and mexico the authors document trends in men s returns to education during the 1980s and the 1990s and estimate the role of supply and demand factors in explaining the changes in skill premia they propose a model of demand for skills with three production inputs corresponding to workers with primary secondary and university level education further the authors demonstrate that an unprecedented rise in the supply of workers having completed secondary level education depressed their wages relative to workers with primary level education throughout latin america this supply shift was compounded by a generalized shift in the demand for workers with tertiary education

improvement of energy demand forecasts using swarm intelligence the case of turkey with projections to 2025 the energy supply and demand should be closely monitored and revised the forecasts to take account of the progress of liberalization energy efficiency improvements structural changes in industry and other major factors medium and long term forecasting of energy demand which is based on realistic indicators is a prerequisite to become an industrialized country and to have high living standards energy planning is not possible without a reasonable knowledge of past and present energy consumption and likely future demands energy demand management activities should bring the demand and supply closer to a perceived optimum turkey s energy demand has grown rapidly almost every year and is expected to continue growing however the energy demand forecasts prepared by the turkey ministry of energy and natural resources overestimate the demand recently many studies are performed by researchers to forecast the energy demand of turkey particle swarm optimization pso technique has never been used for such a study in this study a model is proposed using pso based energy demand forecasting psoedf to forecast the energy demand of turkey more efficiently although there are other indicators as well gross domestic product gdp population import and export are used as basic energy indicators of energy demand in order to show the accuracy of the algorithm a comparison is made with the ant colony optimization aco energy demand estimation model which is developed for the same problem

fair demographic risk sharing in defined contribution pension systems in this article we formulate and solve the optimal design problem of a defined contribution public pension fund in a highly stylized but still rather general non stationary framework we adopt the viewpoint of a benevolent social planner who aims at treating in a fair manner the successive overlapping generations participating to such a long term mandatory system using the approach of el karoui and jeanblanc 1998 for the optimal consumption and portfolio choice problem with random income in a complete market we exhibit a solution to our intertemporal stochastic control problem where each generation receives a fair lumpsum retirement benefit it is proportional to the contributions she has paid during her active worklife and follows a fixed common rule although her pension value itself may depend on variables only observable at her retirement time we next relax the assumption that the collective pension system is mandatory and investigate the performance of individual investment plans in the market comparing the outcomes of both alternatives we derive a condition under which the collective fund can be expected to overperform the individual plan in the special case of a stationary economy such a possibility has been pointed out by gollier 2008 in fact this effect results from the possibility for the collective fund to borrow today against contributions of future generations which allows to implement riskier strategies and may improve its performance

optimal portfolio choice for long horizon investors with nontradable labor income this paper examines how risky labor income and retirement affect optimal portfolio choice with idiosyncratic labor income risk the optimal allocation to stocks is unambiguously larger for employed investors than for retired investors consistent with the typical recommendations of investment advisors increasing idiosyncratic labor income risk raises investors willingness to save and reduces their stock portfolio allocation towards the level of retired investors positive correlation between labor income and stock returns has a further negative effect and can actually reduce stockholdings below the level of retired investors financial advisors typically recommend that their customers invest more in stocks than in safe assets when they are working and to shift their investments towards safe assets when they retire jagannathan and kocherlakota 1996 malkiel 1996 by contrast the standard academic models of portfolio choice merton 1969 1971 samuelson 1969 show that retirement is irrelevant for portfolio decisions if investment opportunities are constant and human capital is tradable in this case the fraction of wealth optimally invested in risky assets should be constant over the lifetime of an individual recent research building on the pioneering work by merton 1971 shows that time varying investment opportunities result in portfolio rules with an intertemporal hedging component whose magnitude depends on the investment horizon of the investor kim and omberg 1996 balduzzi and lynch 1997 brennan schwartz and lagnado 1997 brandt 1999 campbell and viceira 1999 2001 barberis 2000 with time variation in investment opportunities retirement and death play an instrumental role as events that exogenously fix the individual s investment horizon more importantly retirement also marks the time at which individuals stop working and thereafter must live off their lifetime savings and possibly transfers from this perspective retirement matters for portfolio choice

short run demand for palestinian labor palestinian residents of the west bank and gaza strip who work in israel generally earn more than palestinians employed locally but this wage premium is highly volatile beginning with the 1987 palestinian uprising changes in wage differentials by work location parallel palestinian absences from work in israel this article interprets changing location differentials in response to exogenous shocks as movements along an israeli demand curve for migrant workers estimates of a model of the west bank and gaza strip labor market are used to evaluate the effect of policies governing palestinian access to the israeli labor market

retirement saving with contribution payments and labor income as a benchmark for investments abstract in this paper we study the retirement saving problem from the point of view of a plan sponsor who makes contribution payments for the future retirement of an employee the plan sponsor considers the employee s labor income as investment benchmark in order to ensure the continuation of consumption habits after retirement we demonstrate that the demand for risky assets increases at low wealth levels due to the contribution payments we quantify the demand for hedging against changes in wage growth and find that it is relatively small we show that downside risk measures increase risk taking at both low and high levels of wealth

measuring heterogeneity in the returns to education using an education reform abstract in this paper we explore the impact of a mandatory education reform as well as pre reform availability of schools above the mandatory level on educational attainment and returns to education in norway we contribute to the existing literature by focusing on the heterogeneity of the impact of reforms our results indicate that increased compulsory education from seven to nine years increased the general level of education beyond the compulsory education we also find that the effect of family background on educational attainment was weaker after the reform the average treatment effect on returns to education is surprisingly high for education of intermediate duration this means that increasing the general level of education potentially generates high returns in the form of wages we also find that the effect of treatment on the treated on the returns to education is 1 4 percentage points higher than the average treatment effect

benefits to elite schools and the expected returns to education evidence from mexico city we exploit data on the future earnings students at high school completion expect to receive with and without a college education together with information on learning achievement and college outcomes to study the benefits from admission into a system of elite public high schools in mexico city using data for the centralized allocation of students into schools and an adapted regression discontinuity design strategy we estimate that elite school admission increases the future earnings and returns students expect from a college education these gains in earnings expectations seem to reflect improvement in actual earnings opportunities as admission to this elite school system also enhances learning achievement and college graduation outcomes this provides evidence of the earnings benefits from attending elite schools

human capital pricing equations with an application to estimating the effect of schooling quality on earnings this paper formulates and estimates alternative models for the pricing of labor services we present economic models that rationalize empirical specifications in the literature and we offer evidence on the validity of those specifications widely used efficiency units models of labor services are inconsistent with evidence from the u s labor market a model of heterogeneous skills provides a more accurate description of earnings data we present evidence that the pursuit of comparative advantage and selective migration are important features of the u s labor market when these features are included in the model the only support for an effect of schooling quality on earnings is through the return to college education three interactions are empirically important in explaining log wage equations a between schooling quality and education b between regional labor market shocks and education and c between region of residence and regionof birth because of this third interaction which can arise from comparative advantage in the labor market no unique quality effect on returns to education can be defined independently of the market in which it is used

job information networks neighborhood effects and inequality this paper explores the theoretical and empirical literature to examine the use by different social groups of informal sources of information provided by friends relatives and acquaintances during job search and its consequences for the job market it also addresses the role of network structure and size the resource endowments of contacts and nature of the links between contacts to explain differences in the effects of job information networks in doing so the paper also turns to the sociology literature on job information networks and provides an economic perspective on such sociological concepts as strong versus weak ties inbreeding distance from structural holes etc the paper distinguishes between models of exogenous job information networks that is where individuals obtain job related information through a given social structure and endogenous job information networks which are social networks that result from individuals uncoordinated actions the paper pays special attention to such issues as physical and social proximity and sharing of information and discusses them in the context of the recent social interactions and neighborhood effects literature finally the paper outlines a model that integrates job information networks where interactions occur in business cycle frequencies with the dynamics of human capital formation which include the joint effects of parental community and neighborhood human capital and are set in life cycle frequencies for the purpose of organizing suggestions for future research and examining earned income inequality

energy models for demand forecasting a review abstract energy is vital for sustainable development of any nation be it social economic or environment in the past decade energy consumption has increased exponentially globally energy management is crucial for the future economic prosperity and environmental security energy is linked to industrial production agricultural output health access to water population education quality of life etc energy demand management is required for proper allocation of the available resources during the last decade several new techniques are being used for energy demand management to accurately predict the future energy needs in this paper an attempt is made to review the various energy demand forecasting models traditional methods such as time series regression econometric arima as well as soft computing techniques such as fuzzy logic genetic algorithm and neural networks are being extensively used for demand side management support vector regression ant colony and particle swarm optimization are new techniques being adopted for energy demand forecasting bottom up models such as markal and leap are also being used at the national and regional level for energy demand management

the economic returns to schooling in the west bank and gaza strip the author uses micro data from the labor force surveys conducted in the west bank and the gaza strip during 1981 91 to show that during 1981 87 wage differences between schooling groups fell by well over one half this sharp reduction is associated with large increases in the size of the educated palestinian labor force since the returns to schooling for israeli jews were stable the decline in returns to schooling for palestinians is consistent with the notion that the returns to schooling in the territories were determined largely by the forces of supply and demand in a segmented market for skilled labor copyright 1995 by american economic association

energy economic growth and causality in developing countries a case study of tanzania and nigeria the debate about the precise role of energy in economic development remains contentious existing empirical studies have produced varying results some have argued the complementarity between energy and other factors of production and others have indicated that energy can be substituted for other factors of production commonly these studies have focused primarily on the developed countries one explanation being that supply constraints and price rigidities render any study on factor substitutions in developing countries meaningless however the functional relationship between energy consumption and income in developing countries is constantly investigated with the use of regression techniques while such techniques are useful in empirical analysis no mechanism exists for indicating causal directions between variables this limits the scope for policy analysis and prescription the need to identify causal direction between energy consumption and income growth in developing countries is overwhelming apart from providing further insights into the role of energy in economic development it provides policy analysts with a clearer understanding of the likely impact of energy supply constraints on economic growth this article examines the causal directions between energy consumption and economic growth proxied by gdp and gnp for nigeria and tanzania the results show a simultaneous causal relationship between energy and economic growth for both countries the implication being that unless energy supply constraints are eased economic growth and development will remain elusive to these countries given similar economic characteristics and profiling the same energy scenario for other developing countries our finding supports the view that energy plays a key role in economic development

does it pay to attend an elite private college cross cohort evidence on the effects of college type on earnings although a substantial and rising labor market premium is associated with college attendance in general little is known about how this premium varies across institutions of different types and across time in this paper we explicitly model high school students choice of college type characterized by selectivity and control based on individual and family characteristics including ability and parental economic status and an estimate of the net costs of attendance we estimate selectivity corrected outcome equations using data from both the national longitudinal study of the high school class of 1972 and high school and beyond which permit us to determine the effects of college quality on wages and earnings and how this effect varies across time even after controlling for selection effects strong evidence emerges of a significant economic return to attending an elite private institution and some evidence suggests this premium has increased over time

optimal consumption and portfolio policies when asset prices follow a diffusion process abstract we consider a consumption portfolio problem in continuous time under uncertainty a martingale technique is employed to characterize optimal consumption portfolio policies when there exist nonnegativity constraints on consumption and on final wealth we also provide a way to compute and verify optimal policies our verification theorem for optimal policies involves a linear partial differential equation unlike the nonlinear partial differential equation of dynamic programming the relationship between our approach and dynamic programming is discussed we demonstrate our technique by explicitly computing optimal policies in a series of examples in particular we solve the optimal consumption portfolio problem for hyperbolic absolute risk aversion utility functions when the asset prices follow a geometric brownian motion the optimal policies in this case are no longer linear when nonnegativity constraints on consumption and on final wealth are included by these examples one can see that our approach is much easier than the dynamic programming approach

does compulsory school attendance affect schooling and earnings we establish that season of birth is related to educational attainment because of school start age policy and compulsory school attendance laws individuals born in the beginning of the year start school at an older age and can therefore drop out after completing less schooling than individuals born near the end of the year roughly 25 percent of potential dropouts remain in school because of compulsory schooling laws we estimate the impact of compulsory schooling on earnings by using quarter of birth as an instrument for education the instrumental variables estimate of the return to education is close to the ordinary least squares estimate suggesting that there is little bias in conventional estimates every developed country in the world has a compulsory schooling requirement yet little is known about the effect these laws have on educational attainment and earnings 1 this paper exploits an unusual natural experiment to estimate the impact of compulsory schooling laws in the united states the experiment stems from the fact that children born in different months of the year start school at different ages while compulsory schooling laws generally require students to remain in school until their sixteenth or seventeenth birthday in effect the interaction of school entry requirements and compulsory schooling laws compel students born

income schooling and ability evidence from a new sample of identical twins we develop a model of optimal schooling investments and estimate it using new data on approximately 700 identical twins we estimate an average return to schooling of 9 percent for identical twins but estimated returns appear to be slightly higher for less able individuals simple cross section estimates are marginally upward biased these empirical results imply that abler individuals attain more schooling because they face lower marginal costs of schooling not because of higher marginal benefits

the failure of china s energy development strategy 2050 and its impact on carbon emissions china is the world s largest energy consumer and emitter of carbon china s energy development strategy is thus of great significance to the world s energy security and global carbon reduction target in this study the implementation of china s energy development strategy 2050 eds2050 which has been in operation since 1985 is investigated this study analyzes the causes of the failure of eds2050 and the impacts of that failure on carbon emissions the results show the following 1 eds2050 basically failed in 2010 and the strategic planning values of primary energy consumption and production were underestimated compared with the actual values by 39 and 67 respectively 2 comparing the predicted values of basic parameters in eds2050 with the actual values in the production field the main causes of failure were the underestimation of the economic growth rate and the proportion of non agricultural industries while in the living field the main causes were the underestimation of urbanization and per capita energy consumption in rural areas further analyses of various provinces demonstrated that the major factors leading to eds2050 failure include the economic growth rate urbanization population growth and the growth in car ownership 3 eds2050 failure resulted in an increase in carbon emissions in 2010 of 583 50 x 10 6 tc and increases of per capita carbon emissions reached 46 49 47 04 carbon emissions per unit of output demonstrated a reduction which was as a result of technological progress improving energy efficiency optimizing energy utilization and promoting national energy conservation should be highly emphasized in china s future sustainable energy development strategy c 2015 elsevier ltd all rights reserved

a hybrid simulation optimisation scenario model for asset liability management abstract in this paper we desciibe a decision support model to sustain management of pension funds in the strategic planning of the available asset and liability policy instruments a main characteristic of the approach is that the relevant risk drivers are modelled by scenarios rather than by probability distributions we will describe the scenario generation methodology and how the scenarios are used by pension fund managers to simulate and improve asset liability strategies until a strategy is identified which is agreed upon by all who carry responsibility for the pension fund and her sponsors and trustees next we will describe how this process of managerial learning can be improved by a hybrid simulation optimisation method which applies concepts from the field of non linear global optimisation to determine the asset allocations which determine efficient frontiers of contribution rates and downside insolvency risks we will conclude by showing that the application of the developed models to a particular pension fund leads to the annulment of the infeasibility of the current asset liability policy on the one hand and to a reduction of the expected yearly contributions of us 100 million on the other

scenario generation and stochastic programming models for asset liability management in this paper we develop and test scenario generation methods for asset liability management models we propose a multi stage stochastic programming model for a dutch pension fund both randomly sampled event trees and event trees fitting the mean and the covariance of the return distribution are used for generating the coefficients of the stochastic program in order to investigate the performance of the model and the scenario generation procedures we conduct rolling horizon simulations the average cost and the risk of the stochastic programming policy are compared to the results of a simple fixed mix model we compare the average switching behavior of the optimal investment policies our results show that the performance of the multi stage stochastic program could be improved drastically by choosing an appropriate scenario generation method

hedging in incomplete markets with hara utility in the context of merton s original problem of optimal consumption and portfolio choice in continuous time this paper solves an extension in which the investor is endowed with a stochastic income that cannot be replicated by trading the available securities the problem is treated by demonstrating using analytic and in particular viscosity solutions techniques that the value function of the stochastic control problem is a smooth solution of the associated hamilton jacobi bellman hjb equation the optimal policy is shown to exist and given in a feedback form from the optimality conditions in the hjb equation at zero wealth a fixed fraction of income is consumed for large wealth the original merton policy is approached we also give a sufficient condition for wealth under the optimal policy to remain strictly positive

stochastic pension funding when the benefit and the risky asset follow jump diffusion processes we study the asset allocation of defined benefit pension plans of the type designed and sponsored by firms with the aim of providing a lifetime pension to the employees at the age of retirement benefits are stochastic combining poisson jumps with brownian uncertainty the sponsor dynamically forms portfolios where the risky asset is also subjected to poisson jumps and brownian uncertainty possibly correlated with the evolution of benefits the objective is to assure future benefits while controlling the contribution made to the fund reserves the problem is solved analytically using dynamic programming techniques

vision 2023 forecasting turkey s natural gas demand between 2013 and 2030 abstract natural gas is the primary source for electricity production in turkey however turkey does not have indigenous resources and imports more than 98 0 of the natural gas it consumes in 2011 more than 20 0 of turkey s annual trade deficit was due to imported natural gas estimated at us 20 0 billion turkish government has very ambitious targets for the country s energy sector in the next decade according to the vision 2023 agenda previously we have estimated that turkey s annual electricity demand would be 530 000 gwh at the year 2023 considering current energy market dynamics it is almost evident that a substantial amount of this demand would be supplied from natural gas however meticulous analysis of the vision 2023 goals clearly showed that the information about the natural gas sector is scarce most importantly there is no demand forecast for natural gas in the vision 2023 agenda therefore in this study the aim was to generate accurate forecasts for turkey s natural gas demand between 2013 and 2030 for this purpose two semi empirical models based on econometrics gross domestic product gdp at purchasing power parity ppp per capita and demographics population change were developed the logistic equation which can be used for long term natural gas demand forecasting and the linear equation which can be used for medium term demand forecasting fitted to the timeline series almost seamlessly in addition these two models provided reasonable fits according to the mean absolute percentage error mape criteria turkey s natural gas demand at the year 2030 was calculated as 76 8 billion m 3 using the linear model and 83 8 billion m 3 based on the logistic model consequently found to be in better agreement with the official turkish petroleum pipeline corporation botas forecast 76 4 billion m 3 than results published in the literature

college choice and subsequent earnings results using swedish sibling data college choice and subsequent earnings results using swedish sibling data this paper investigates the relationship between college choice and annual earnings using within family variation in college choice the results show that earnings vary significantly between students who graduated from different types of colleges and the earnings premium is larger for those who graduated at an old university do birth order and family size matter for intergenerational income mobility evidence from sweden previous studies of intergenerational income mobility have not considered potential birth order or family size effects in the estimated income elasticity this paper estimates the intergenerational income elasticity by birth order position and family size the main finding of this paper is that the elasticity tends to decrease with birth order for a given family size especially for fathers and sons a comparison of family and neighborhood effects on grades test scores educational attainment and income evidence from sweden this paper compares sibling and neighborhood correlations in school performance educational attainment and income as a way to learn whether the neighborhood where a child grows up in might explain parts of the sibling similarities found in previous sibling correlation studies the results show that living in the same neighborhood does not seem to add much to the sibling similarity what more than parental income an exploration of what swedish siblings get from their parents in this paper we explore what factors other that parental income can explain why siblings tend to have such similar outcomes as previous correlation studies show our results show that parental involvement and attitudes especially propensity to plan ahead and willingness to postpone benefits to the future are particularly important for the sibling similarity

college choice and wages estimates using data on female twins the authors assess the impact of college quality on women s earnings and the influence of family and individual endowments on college choice using new data from a survey of identical and nonidentical twins born in minnesota the estimates reject models that ignore school choice the statistically preferred estimates suggest that ph d granting private universities with well paid senior faculty and smaller enrollments produce students who have significantly higher earnings later in life both the quantity of schooling and the quality of schooling resources are allocated to higher endowed individuals which exacerbates preexisting inequality in human capital and biases conventional estimates of school quality effects copyright 1996 by mit press

ant colony optimization approach to estimate energy demand of turkey abstract this paper attempts to shed light on the determinants of energy demand in turkey energy demand model is first proposed using the ant colony optimization aco approach it is multi agent systems in which the behavior of each ant is inspired by the foraging behavior of real ants to solve optimization problem aco energy demand estimation acoede model is developed using population gross domestic product gdp import and export all equations proposed here are linear and quadratic quadratic acoede provided better fit solution due to fluctuations of the economic indicators the acoede model plans the energy demand of turkey until 2025 according to three scenarios the relative estimation errors of the acoede model are the lowest when they are compared with the ministry of energy and natural resources menr projection

changes in college skills and the rise in the college wage premium the college wage premium for new labor market entrants rose sharply during the 1980s we ask how much of this change arose from changes in the skill level of the typical college graduate we find that skills attained prior to college as measured by standardized test scores and high school grades had no effect on the change in the college wage premium for men in contrast the returns to math ability rose considerably for women failing to account for math skills thus substantially overstates the growth in the female college wage premium skills acquired in college as reflected in the distribution of students across majors had important effects on the relative wages of men the trend away from low skill subjects such as education and toward high skill subjects such as engineering accounts for one fourth of the rise in the male college wage premium

arima forecasting of primary energy demand by fuel in turkey abstract forecasting of energy demand in emerging markets is one of the most important policy tools used by the decision makers all over the world in turkey most of the early studies used include various forms of econometric modeling however since the estimated economic and demographic parameters usually deviate from the realizations time series forecasting appears to give better results in this study we used the autoregressive integrated moving average arima and seasonal arima sarima methods to estimate the future primary energy demand of turkey from 2005 to 2020 the arima forecasting of the total primary energy demand appears to be more reliable than the summation of the individual forecasts the results have shown that the average annual growth rates of individual energy sources and total primary energy will decrease in all cases except wood and animal plant remains which will have negative growth rates the decrease in the rate of energy demand may be interpreted that the energy intensity peak will be achieved in the coming decades another interpretation is that any decrease in energy demand will slow down the economic growth during the forecasted period rates of changes and reserves in the fossil fuels indicate that inter fuel substitution should be made leading to a best mix of the country s energy system based on our findings we proposed some policy recommendations

schooling and labor market consequences of school construction in indonesia evidence from an unusual policy experiment between 1973 and 1978 the indonesian government engaged in one of the largest school construction programs on record combining differences across regions in the number of schools constructed with differences across cohorts induced by the timing of the program suggests that each primary school constructed per 1 000 children led to an average increase of 0 12 to 0 19 years of education as well as a 1 5 to 2 7 percent increase in wages this implies estimates of economic returns to education ranging from 6 8 to 10 6 percent

consumption and portfolio policies with incomplete markets and short sale constraints the infinite dimensional case abstract we employ a martingale approach to study a dynamic consumption portfolio problem in continuous time with incomplete markets and short sale constraints we introduce a notion of minimax local martingale and transform the dynamic problem into a static problem of maximizing expected utility over the consumption bundles that satisfy a single budget constraint formed using that measure we establish the existence of and characterize the minimax local measure provide sufficient conditions for the dynamic consumption portfolio problem to have a solution and relate the optimal policies to the solution of quasi linear partial differential equation

factor proportions and relative wages the supply side determinants of wage inequality supply side factors may contribute to rising wage inequality first certain changes in the supply of skills allegedly exacerbate wage inequality women s increased labor force participation and increased immigration are the leading candidates both allegedly reduce the wages of less skilled men however immigration s impact on wage inequality has been minor and the effects of women s participation is inconclusive second in evaluating the likelihood that human capital investment will mitigate future inequality evidence suggests that rising returns to education have increased the proportion of young people attending college limiting the growth of inequality among high wage workers

energy consumption and gdp in turkey is there a co integration relationship energy consumption and gdp are expected to grow by 5 9 and 7 annually until 2025 in turkey this paper tries to unfold the linkage between energy consumption and gdp by undertaking a co integration analysis for turkey with annual data over the period 1970 2003 the analysis shows that energy consumption and gdp are co integrated this means that there is a possibly bi directional causality relationship between the two we establish that there is a unidirectional causality running from gdp to energy consumption indicating that energy saving would not harm economic growth in turkey in addition we find that energy consumption keeps on growing as long as the economy grows in turkey

explaining international differences in male skill wage differentials by differences in demand and supply of skill this paper explores the hypothesis that wage differentials between skill groups across countries are consistent with a demand and supply framework using micro data from 15 countries we find that about one third of the variation in relative wages between skill groups across countries is explained by differences in net supply of skill groups the demand and supply framework does an even better job at explaining relative wages of low skilled workers

energy diversity and development in economic systems an empirical analysis abstract as economic systems develop over time they tend to become more complex with more structure and greater throughputs assuming favorable conditions energy use increases as more economic sectors develop and more channels for flow are opened economic diversity as measured by the number of economic sectors using energy and the equatability of flows between them generally increases as diversity increases the efficiency of generating outputs with a given amount of energy also increases development capacity the product of system energy throughput and diversity of flows is a measure of the potential system output and is calculated for selected countries capacity changes over time are shown to relate to changes in economic output in selected countries two distinct development strategies become evident one which promotes energy use and one which emphasizes diversity and the sustainability of each is examined while most countries utilize a mix of the two developing countries generally rely more on increasing energy use to increase output while developed countries tend to become more diverse as a means of increasing outputs sustainability is enhanced by strategies which promote diversity and resource use efficiency in economic systems