understanding responses to supply chain disruptions insights from information processing and resource dependence perspectives why how and under what conditions do firms respond to supply chain disruptions these are important questions given that firms around the world are increasingly exposed to disruptions that impede their supply chain relationships and associated operations this study applies information processing and resource dependence perspectives to identify the repertoire of strategic responses to supply chain disruptions and to devise and test a model that explains the occurrence of the alternative responses the findings suggest that these responses are shaped by the stability motive and by interpretative postures which evolve from past experiences

evaluating natural resource investments notwithstanding impressive advances in the theory of finance over the past 2 decades practical procedures for capital budgeting have evolved only slowly the standard technique which has remained unchanged in essentials since it was originally proposed see dean 1951 bierman and smidt 1960 derives from a simple adaptation of the fisher 1907 model of valuation under certainty under this technique expected cash flows from an investment project are discounted at a rate deemed appropriate to their risk and the resulting present value is compared with the cost of the project this standard textbook technique reflects modern theoretical developments only insofar as estimates of the discount rate may be obtained from crude application of single period asset pricing theory but see brennan 1973 bogue and roll 1974 turnbull 1977 constantinides 1978 the inadequacy of this approach to capital budgeting is widely acknowledged although not widely discussed its obvious deficiency is its the evaluation of mining and other natural resource projects is made particularly difficult by the high degree of uncertainty attaching to output prices it is shown that the techniques of continuous time arbitrage and stochastic control theory may be used not only to value such projects but also to determine the optimal policies for developing managing and abandoning them the approach may be adapted to a wide variety of contexts outside the natural resource sector where uncertainty about future project revenues is a paramount concern

counterfactual decomposition of changes in wage distributions using quantile regression we propose a method to decompose the changes in the wage distribution over a period of time in several factors contributing to those changes the method is based on the estimation of marginal wage distributions consistent with a conditional distribution estimated by quantile regression as well as with any hypothesized distribution for the covariates comparing the marginal distributions implied by different distributions for the covariates one is then able to perform counterfactual exercises the proposed methodology enables the identification of the sources of the increased wage inequality observed in most countries specifically it decomposes the changes in the wage distribution over a period of time into several factors contributing to those changes namely by discriminating between changes in the characteristics of the working population and changes in the returns to these characteristics we apply this methodology to portuguese data for the period 1986 1995 and find that the observed increase in educational levels contributed decisively towards greater wage inequality copyright 2005 john wiley sons ltd

the effect of cohort size on earnings growth a reexamination of the evidence this study reexamines the effect of cohort size on earnings growth finis welch finds that individuals in larger cohorts experience depressed earnings conditions on entry into the labor market but that their earnings grow at faster rates than in smaller cohorts thus a large portion of the cohort size effect on earnings dissipates after a few years however using data almost identical to those of welch but estimating less restrictive models it is found here that cohort size not only depresses earnings at entry but also seems to slow down early career earnings growth the evidence suggests that earnings ini larger cohorts do not approach normal levels after at brief period in the labor force rather the negative cohort size effect on earnings appears to worsen with experience

economic growth in a cross section of cities abstract we examine the relationship between urban characteristics in 1960 and urban growth between 1960 and 1990 income and population growth move together and both types of growth are 1 positively related to initial schooling 2 negatively related to initial unemployment and 3 negatively related to the initial share of employment in manufacturing racial composition and segregation are uncorrelated with urban growth across all cities but in cities with large nonwhite communities segregation is positively correlated with population growth government expenditures except for sanitation are uncorrelated with growth government debt is positively correlated with later growth

minimization of disruption related return flows in the supply chain abstract recent research on closed loop supply chains sc and reverse logistics extensively emphasises the crucial role of reducing negative return flows such as emissions waste etc in this study we consider the return flows in the sc in light disruptive events in the sc the objective of this study is to compare the performance impact of different recovery policies on return flows subject to the simultaneously optimized re configuration plans for material flows we formulate a multi objective problem with return flow reduction function for a multi period multi stage multi product sc we consider a recovery problem with ripple effect performance impact assessment and re planning decisions the developed multi objective hybrid linear programming system dynamics model allows simultaneously re computing the material flows in a multi stage sc after a disruption and comparing the performance impact of different recovery policies subject to return flows gradual capacity recovery variable recovery costs and time the results suggest that the consideration of gradual capacity recovery leads to minimization of disruption related return flows in both upstream and downstream sc parts fast and expensive recovery strategy provides the lowest return costs in the upstream sc part as compared to normal and slow recovery policies similar the profits and service levels are increased in the fast and expensive recovery policy the performance in the upstream and downstream does not change with the introduction of the gradual recovery considerations the effects of gradual capacity recovery introduction become evident if smaller time sub periods are considered within the recovery period

the impact of the 1962 repatriates from algeria on the french labor market this paper uses census data to examine the impact on the french labor market of the 900 000 people repatriated from algeria in 1962 repatriates settled in regions culturally and climatically simil

distributive shares in the us economy 1964 2001 specifying the labour theory of value in a way that distinguishes both productive from unproductive labour and production workers from supervisory workers this paper considers distributive shares in the us economy between 1964 and 2001 trends in productive and unproductive labour are explored in full time equivalents hours and money after 1979 there was a large shift of money value not matched by a shift in either hours or employment from the wages paid to productive labour to those paid to supervisory labour since the wage share in money value added of non supervisory labour in unproductive sectors was approximately constant the 1980s and 1990s also saw the profits share squeezed by the rising wage share of supervisory workers some implications of this are explored in the construction of a class rather than a factor approach to distributive shares

pattern formation spatial externalities and regulation in coupled economic ecological systems abstract we study the management of ecosystems in which interacting state variables that are affected by management decisions diffuse in space we study pattern formation first in a setting where economic agents maximize myopic profits and ignore spillovers onto agents at other sites and second in the context of a social planner who internalizes these spillovers we compare patterns under these two institutions and study how the differences in the patterns generated by these two institutions impact the design of regulatory schemes to internalize the externalities at the same time we introduce new methods based on fourier series type decompositions that enable us to turn an intractable infinite dimensional optimal control problem into a countable number of finite dimensional optimal control problems as far as we know these methods are new to the economics literature our theory is applied to the management and regulation of a semi arid system

educational opportunity and income inequality affordable higher education is and has been a key element of social policy in the united states with broad bipartisan support financial aid has substantially increased the number of people who complete university generally thought to be a good thing we show however that making education more affordable can increase income inequality the mechanism that drives our results is a combination of credit constraints and the signaling role of education first explored by spence 1973 when borrowing for education is difficult lack of a college education could mean that one is either of low ability or of high ability but with low financial resources when government programs make borrowing easier or tuition more affordable high ability persons become educated and leave the uneducated pool driving down the wage for unskilled workers and raising the skill premium

religion and female educational attainment the paper reviews the literature on the education gender and religion nexuses and identifies plausible hypotheses that religion adversely affects female education the link between major religions and female educational attainment is examined using the barro lee data set for a sample of 97 countries the estimates include control variables for colonial heritage urbanization labor force participation and young adult mortality the estimates show powerful negative links between female educational attainment and the proportion of ethnoreligions hindu and muslim adherents in a country with similar results for the gender gap the paper offers some interpretative thoughts and research agendas

regional labor markets and the determinants of wage inequality from 1972 to 1990 the united states experienced the largest increase in wage inequality of any developed country the spread in log wages between the 90th and 10th percentiles of the male wage distribution increased by about 60 points and inequality increased within virtually every demographic or skill category of the labor force see chinhui juhn et al 1993 various explanations have been offered including changes in the relative demand for skill intensive goods international trade immigration of less skilled workers and increased labor force participation of women yet attempts to quantify the relative importance of these factors have not met with much success this leaves skill biased technical change as the residual claimant that rationalizes the data this paper uses regional differences in the evolution of wage inequality to provide new evidence on the determinants of relative wages using a model of factor demand in geographic markets i isolate contributions of i changing skill ratios in the labor force ii increased participation of women iii technical change and iv changes in the industrial composition of labor demand the data indicate that changing skill ratios and women s labor supply have affected the wages of low skilled men in the west the data indicate that increased immigration of less skilled hispanic and asian workers has adversely affected the wages of natives causing a greater increase in inequality there than in any other region of the country i modeling wage inequality in regional markets

a theory of urban growth in an economy experiencing endogenous economic growth and exogenous population growth we explore two main themes how urbanization affects efficiency of the growth process and how growth affects patterns of urbanization localized information spillovers promote agglomeration and human capital accumulation fosters endogenous growth individual city sizes grow with local human capital accumulation and knowledge spillovers and city numbers generally increase which we demonstrate is consistent with empirical evidence we analyze whether local governments can successfully internalize local dynamic externalities in addition we explore how growth involves real income differences across city types and how urbanization can foster income inequality most nonagricultural production in developed countries occurs in metropolitan areas the underlying reasons why economic activity agglomerates into cities localized information and knowledge spillover also make cities the engines of economic growth in an we gratefully acknowledge support of the national science foundation grants sbr 9422440 and sbr9730142 for this research the work has benefited from conversations with harl ryder on the dynamics of the model and from comments by gilles duranton and participants in seminars at brown colorado and texas austin and a presentation at an isit seminar sponsored by the centre for economic policy research and the national bureau of economic research

immigrants minorities and labor market competition this paper investigates the extent of labor market competition among immigrants minorities and the native population an analysis of 1980 u s census data reveals that immigrants tend to be substitutes for some labor market groups and complements for others the effects of shifts in immigrant supply on the earnings of native born men are however very small on the other hand increases in the supply of immigrants do have a sizable impact on the earnings of immigrants themselves an increase of 10 percent in the supply of immigrants for example reduces the immigrant wage by about 10 percent

optimal harvesting of stochastic spatial resources abstract we characterize the optimal harvest of a renewable resource in a generalized stochastic spatially explicit model despite the complexity of the model we are able to obtain sharp analytical results we find that the optimal harvest rule in general depends upon dispersal patterns of the resource across space and only in special circumstances do we find a modified golden rule of growth that is independent of dispersal patterns we also find that the optimal harvest rule may include closure of some areas to harvest either on a temporary or permanent basis biological reserves reserves alone cannot correct open access but may under sufficient spatial heterogeneity and connectivity increase profits if appropriate harvest controls are in place outside of reserves

on the distributional aspects of urban growth abstract although many theories of urban growth have broad implications regarding the dynamics of wage inequality little empirical work has explored the issue this paper studies the relationship between the growth of three measures of economic activity population employment and per capita income and a variety of wage dispersion measures across a sample of us metropolitan areas between 1970 and 1990 overall the results indicate a negative association between the two cities experiencing more rapid growth also tend to witness smaller increases or larger decreases in their inequality such findings offer some support to theories stressing growth mechanisms which equalize productivity across workers

policy effectiveness in spatial resource wars a two region model abstract we develop a spatial resource model in continuous time in which two agents strategically exploit a mobile resource in a two region setup to counteract the overexploitation of the resource the tragedy of commons that occurs when players are free to choose where to harvest the regulator can establish a series of spatially structured policies we compare the equilibria in the case of a common resource with those that emerge when the regulator either creates a natural reserve or assigns territorial user rights to the players we show that when technological and preference parameters dictate a low harvesting effort the policies are ineffective in promoting the conservation of the resource and in addition they lead to a lower payoff for at least one of the players conversely in a context of higher harvesting effort the intervention can help to safeguard the resource preventing extinction while also improving the welfare of both players

opening a can of worms the pitfalls of time series regression analyses of income inequality this paper argues that time series regression analysis is of only very limited use for understanding the determinants of income inequality the argument is based on a combination of results from the time series econometrics literature and several characteristics of inequality itself principally nonstationarity of the data in most inequality regression models and the weak theoretical foundations underlying the models a sample of postwar us data is used to illustrate the problems involved

optimal harvesting of a spatial renewable resource abstract in this paper we investigate the optimal harvesting of a renewable natural resource while in most standard approaches the resource is located at a single point we allow the resource to be distributed spatially consequently an agent who exploits the resource has to travel from one location to another for a fixed planning horizon we investigate the speed and the path of harvesting chosen by the agent we show that the agent adjusts this speed so as to visit each location only once even in the absence of travelling cost since the agent does not return to any location for a second harvest it is optimal to fully deplete the resource upon arrival a similar type of bang bang solution results when we drop the assumption of a constant harvesting rate allowing for a variable harvesting rate the agent chooses to fully exploit the resource either in the last or in the first travelling period a society interested in conserving some of the resource thus has to take measures to limit the exploitative behaviour of the agent

wage inequality and returns to skill in taiwan 1978 96 since 1980 income inequality has risen faster in taiwan than in the united states inequality rose despite a rapid increase in the share of educated workers in the labour market that might have been expected to depress returns to education returns to a college education rose in taiwan for all but the least experienced college graduates who were the most substitutable by the large new cohorts of college graduates this pattern of changes in relative employment and relative wages is consistent with persistent shifts in relative demand toward skilled labour the shifts are not sector specific as might have been the case if shifts in trade flows were responsible for the shifts in relative wages growth of relative employment of more educated workers occurred in all sectors of the economy consistent with the hypothesis of skill biased technical change these results are similar to findings reported for oecd countries suggesting that taiwan has been exposed to the same types of skill biased shifts in relati

a multi objective stochastic programming approach for supply chain design considering risk abstract in this paper we develop a multi objective stochastic programming approach for supply chain design under uncertainty demands supplies processing transportation shortage and capacity expansion costs are all considered as the uncertain parameters to develop a robust model two additional objective functions are added into the traditional comprehensive supply chain design problem so our multi objective model includes i the minimization of the sum of current investment costs and the expected future processing transportation shortage and capacity expansion costs ii the minimization of the variance of the total cost and iii the minimization of the financial risk or the probability of not meeting a certain budget the ideas of unreliable suppliers and capacity expansion after the realization of uncertain parameters are also incorporated into the model finally we use the goal attainment technique to obtain the pareto optimal solutions that can be used for decision making

do inter city differences in intra city wage differentials have any interesting implications abstract recent research has related characteristics of cities to differences in the distribution of wages across workers with different skill levels we demonstrate that these differences in wage differentials arise naturally as a compensating variation in rosen s theoretical model of inter city wages for example if the income elasticity of demand for housing services is less than unity cities with higher house prices will have smaller money wage differentials between low and high skill workers this result has no implications for differences in either absolute or relative real productivity or welfare of unskilled workers similarly changes in the amenity of an urban area may result in changes in relative wages of skilled and unskilled workers with no implications for real productivity or welfare differentials empirical tests in which housing cost differentials are added as a determinant of inter city differences in an intra urban wage differential model provide empirical confirmation of the theoretical expectations it appears that intra urban money wage differentials differences in the quality of life and variation in the cost of living in each city are jointly determined variables just as rosen s model of inter city wage differentials predicts

does the labour supply of wives respond to husbands wages canadian evidence from micro data and grouped data using micro data and grouped data we assess the extent to which canadian wives adjusted their labour supply in response to changes in husbands wages during the period 1980 2000 grouped data parameters based on weighted least squares and the unbiased error in variables estimator developed by devereux 2004 2007a b yield cross wage elasticities that are substantially higher in absolute value than those derived from ols regressions run on micro data both grouping estimators indicate that the labour supply of canadian wives responded strongly to changes in husbands wages during the 1980s for the 1990s our estimates of wives cross wage elasticity display greater dispersion a l aide de micro donnees et de donnees groupees on etablit jusqu a quel point les epouses canadiennes ont ajuste leur offre de travail en reponse aux changements dans les salaires de leurs epoux au cours de la periode 1980 2000 les parametres pour les donnees groupees derives par la methode des moindres carres ponderes et de l estimateur developpe par devereux 2004 2007a b engendrent des elasticites croisees qui sont substantiellement plus grandes en termes absolus que ceux derives par la methode des moindres carres ordinaires en utilisant des micro donnees les deux estimations montrent que l offre de travail des epouses canadiennes a repondu fortement aux changements dans les salaires des epoux au cours des annees 80 pour les annees 90 les evaluations des elasticites croisees des salaires montrent une plus grande dispersion

earnings mobility in times of growth and decline argentina from 1996 to 2003 summary in recent years argentina s economy has experienced both rapid growth and severe decline in this paper we use a series of one year long panels to study who gained the most in pesos when the economy grew and who lost the most in pesos when the economy contracted various considerations led us to expect that mobility would be divergent that is that the individuals who started with the highest initial earnings would enjoy the largest earnings gains in pesos contrary to expectations and for a wide range of specifications mobility is found to be mostly convergent sometimes neutral and never divergent

banking structure and employment growth recent studies have documented an association between financial structure and per capita income growth the relationship between financial structure and job growth by contrast is an unexplored issue of independent interest here we find that us nonmetropolitan employment grew faster in 1973 1996 where there were fewer locally owned bank offices and a more concentrated initial banking market structure these linkages were less stable in metropolitan areas in addition controlling for employment growth does not undermine the empirical linkage between initial bank structure and subsequent per capita income growth

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

the price of experience we identify a key role of factor supply driven by demographic changes in shaping several empirical regularities that are a focus of active research in macro and labor economics in particular demographic changes alone can account for the large movements of the return to experience over the last four decades for the differential dynamics of the age premium across education groups emphasized by katz and murphy 1992 for the differential dynamics of the college premium across age groups emphasized by card and lemieux 2001 and for the changes in cross sectional and cohort based life cycle profiles emphasized by kambourov and manovskii 2005 jel d91 e24 i23 j11 j24 j31