armington elasticities for energy policy modeling evidence from four european countries elasticities of substitution among imports and competing domestic production armington elasticities play an important role in computable general equilibrium cge assessments of energy and climate policy this paper provides estimates of armington elasticities for 15 commodity groups in four european countries since armington elasticities are found to be rather low on average researchers may want to reconsider the device of using high values of armington elasticities in cge models to avoid unrealistic competitiveness effects or emission leakage rates associated with energy or carbon taxes or other forms of energy related regulation estimated elasticities tend to be higher in the case of machinery and other investment goods than in the case of primary products ores and chemicals as well as consumer goods

armington models and terms of trade effects some econometric evidence for north america elasticities of substitution among u s imports from mexico canada the rest of the world and competing domestic production are estimated for twenty two mining and manufacturing sectors based on quarterly data for 1980 88 these elasticities will provide a benchmark for computable general equilibrium models of north american trade liberalization the authors also find that estimated armington elasticities are low and therefore researchers may want to reconsider the device of using high values of armington elasticities in multicountry computable general equilibrium models to avoid large terms of trade losses associated with preferential trade liberalization

an update and extension of the canadian evidence on gender wage differentials the paper utilizes the 1989 labour market activity survey to examine the gender wage differential in canada the aim is to update previous studies and extend earlier analysis in two significant ways first occupation is treated as endogenously determined secondly the zabalza and arrufat 1985 imputation method is utilized to estimate the level of female labour market experience the results suggest that the level of estimated gender discrimination is sensitive to the measure of labour market experience the paper also concludes that intra occupation wage effects explain most of gender wage gap

the gender earnings differential in the russian transition economy using data from the russia longitudinal monitoring survey rlms the first nationally representative household survey in the russian federation the author examines the gender earnings differentia

the eec s wheat trade policies and international trade in differentiated products reply in a recent issue of the journal von cramon taubadel vct comments on our work de gorter and meilke and uses the terms misspecification questionable incorrect conclusions and erroneous results in a recent survey of the new trade theory and imperfect substitutes in agricultural trade maclaren p 129 concludes that our approach is the best methodology for specifying the demand side of trade models and the relationships between imperfect substitutes in agricultural trade however in reference to vct maclaren p 128 makes a qualification by stating that our approach has been used with only some success because of specification errors it is our contention that both vct and

turnover in the afdc population an event history analysis the control group of families with female heads from the denver income maintenance experiment is utilized in this analysis of afdc turnover this study uses event history techniques a methodology that is more appropriate for exploring welfare dynamics than the logit approach of earlier work increases in age and the wage have significant negative effects on the rate of entering afdc a higher guarantee raises this rate significantly age and the guarantee have significant effects with opposite signs on the exit rate other variables are not systematically related to turnover the estimates are applied to projected changes in lengths of time spent on and off afdc and in afdc caseloads due to changes in the explanatory variables

the structure of the female male wage differential is it who you are what you do or where you work the efficacy of policies to narrow the malelfemale wage differential depends partly on the size of the portion s of the gap targeted previous research finds no between sex wage gap within occupations within employer job cell this is the first study to disentangle segregation by occupation from that based on employer or on job cell in five industries controlling for other forms of segregation occupational segregation produces a gap of 11 percent manufacturing to 26 percent services the wage gaps from establishment and job cell segregation are about 6 percent each since comparable worth acts on the occupation and job cell components it has a potentially large impact

the changing empirical definition of money some estimates from a model of the demand for money substitutes interest bearing checkable deposits are examined to test whether they should be included in measures of the u s money stock both divisia and traditional simple sum aggregates are constructed on the basis of tests for weak separability in a model of the demand for financial assets using nonparametric demand analysis we find that several groups of assets are compatible with aggregation theory we find empirical support for a narrow measure consisting of the components of current mia in tests based on a st louis equation and in terms of controllability a divisia aggregate performs better than the simple sum mia measure

source diversification and import price risk in this article i present a theoretical framework and derive an empirical model that relates import price risk to the allocation of an import across exporting sources source diversification a differential approach to expected utility theory and firm demand is used to derive a model comparable to more popular demand systems such as the rotterdam and aids models the model is used in estimating carnation demand in the united kingdom results show that while total carnation imports expected prices and seasonality are important determinants of import demand by source there is significant information loss when price risk is not considered copyright 2012 oxford university press

the wage effect of the occupational segregation of women in britain married females earn around 60 percent of the male rate of pay part of this wage difference der ives from inequality of pay within occupations and part derives from the different occupational distributions of the male and female workf orces this paper merges models of occupational attainment and gender wage distributions it shows that the gender wage difference derives largely from wage differences within occupations the effect of fema le nonparticipation in the paid workforce is found to be an important aspect of occupational attainment as well as of pay differences with in occupations copyright 1987 by royal economic society

variable earnings and nonlinear taxation tax and transfer programs transform before tax income into after tax income income is variable and the tax and transfer system is nonlinear i e marginal tax rates vary we show that as a consequence the tax and transfer system punishes and rewards income variability we calculate the effect of the nonlinearity for several components of the u s tax and transfer system focusing on the low income population we find that the system rewards variability for some individuals and penalizes it for others we conclude that the tax and transfer system punishes and rewards variability in a manner that is both substantial and capricious

a generalized armington trade model respecification abstract even if the original version of the armington model is simple and plausible in estimation the single ces and homotheticity assumptions are too restrictive for practical application and give biased price elasticities this paper develops a generalized armington model which relaxes the single ces and homotheticity restrictions and includes the armington model as a special case the armington and generalized armington trade models are applied to the japanese meat import demand to demonstrate their performance the empirical results rejected the two assumptions imposed on the armington model the generalized armington model provides an alternative to the restrictive but indispensable armington model

does the level of occupational aggregation affect estimates of the gender wage gap the traditional decomposition of the gender wage gap distinguishes between a component attributable to gender differences in productivity related characteristics and a residual component that is often taken as a measure of discrimination this study of data from the 1989 canadian labour market activity survey shows that when occupation is treated as a productivity related characteristic the proportion of the gender wage gap labeled explained increases with the number of occupational classifications distinguished however on the basis of evidence that occupational differences reflect the presence of barriers faced by women attempting to enter male dominated occupations the authors conclude that occupation should not be treated as a productivity related characteristic and in a decomposition of the gender wage gap that treats occupation as endogenously determined they find that the level of occupational aggregation has little effect on the size of the explained component of the gap

macroeconomics financial variables and computable general equilibrium models abstract this paper surveys micro macro computable general equilibrium cge models that incorporate asset markets and product and factor markets recent models are designed to analyze the impact on economic performance and the distribution of income in developing economies of structural adjustment and stabilization programs implemented in response to macro shocks these financial cge models add a loanable funds market incorporating a variety of assets to a cge model that already incorporates flow equilibria in product and factor markets these financial models start from tradefocused cge models and also draw on earlier work with micro and macrostructuralist models in specifying the interactions between financial variables and the real side of the economy the paper also compares these models to dynamic macro models both short run adaptive models with lagged adjustment mechanisms and longer run forward looking models the paper discusses the theoretical problems such models face in reconciling micro focused cge models with macro models incorporating dynamic behavior

market delineation and demand structure this paper addresses the relationship between the cointegration approach to market delineation and the more traditional approach of analyzing the demand structure among different products in terms of degree of substitutability cointegration tests for market delineation and estimation of a dynamic system of demand equations are undertaken utilizing the same data set the data set consists of three high quality seafood products in the european union the results are encouraging as the results from the two approaches are not only compatible but are also complementary in the sense that they provide more information together than they do separately

welfare reform when recipients are forward looking in 1996 the aid to families with dependent children program was replaced with the temporary assistance for needy families tanf program this paper considers the effects of two specific components of tanf time limits and work requirements on employment marriage and welfare participation a discrete choice dynamic programming model is used and parameter estimates are obtained using data from the panel study of income dynamics policy simulations show that a five year lifetime time limit results in a 60 percent reduction in welfare use and that a substantial part of this reduction occurs because recipients are forward looking

wheat demand in japanese flour milling industry a production theory approach a production approach based on the translog cost function is used to analyze import demand for wheat differentiated by class and country of origin in the japanese wheat flour milling industry results indicate that us wheat faces strong competition in the japanese wheat market but its multiple classes and end use characteristics enable the us to preserve the largest market share in japan

european community enlargement and world trade in fruits and vegetables world trade models for the product classes fresh fruits dried fruits processed fruits fresh vegetables and processed vegetables are estimated and used to project the impact on export prices and trade patterns likely to arise after the european economic community enlargement with greece portugal and spain the results indicate that current world trends in import demands and export supplies if continued and in the absence of enlargement will cause marked declines of export prices for four of the above product categories except dried fruits the enlargement will not significantly modify these price projections but it will divert a significant part of european community imports of these products to the three new member countries on 1 january 1981 greece became the tenth country to join the european community ec spain and portugal have also applied for full ec membership and negotiations are underway with an anticipated date of both spanish and portuguese accession of 1986 agriculture has loomed large in the enlargement negotiations with spain greece and portugal sgp given that the national product in these three countries depends much more on agriculture than in the average country of the former ec nine within agriculture

equal pay as a moving target international perspectives on forty years of addressing the gender pay gap this paper provides an overview of the key factors impacting upon the gender pay gap in the uk europe and australia forty years after the implementation of the first equal pay legislation the pay gap remains a key aspect of the inequalities women face in the labour market while the overall pay gap has tended to fall in many countries over the past forty years it has not closed in some countries it has been stubbornly resistant or has even widened in reviewing the collection of papers that make up this special issue we identify four broad themes with which to group the contributions and draw out the explanations for diverse trends theoretical and conceptual debates legal developments and their impacts wage setting institutions and changing employer demands and newly emerging pay inequalities between and within educational and ethnic groups across the four themes we underline how the trends in the gender pay gap capture the dynamism of inequalities as the market power of different groups and stakeholders changes over times three key dimensions emerge from the papers to provide a framework for future research and policy discourse the relationship between litigation and bargaining strategies the interaction between wage setting institutions and new organisational practices and the increasing and range of diversity or equality strands competing for equal treatment we conclude that progress towards closing the gender pay gap will not be easy will require a collective effort of various actors and will not be quick

maintaining and testing separability in demand systems we derive a general elasticity representation of the necessary and sufficient conditions for direct weak separability of the utility function parametric restrictions required to implement the separability conditions are presented for three common demand systems the almost ideal translog and rotterdam our empirical application uses the rotterdam model to test a few separable structures within a complete u s demand system emphasizing food commodities results based on size corrected likelihood ratio tests provide support for commonly used separability assumptions about food and meat demand

price and income elasticities of disaggregated import demand results from uecms and an application this paper presents an empirical analysis of the demand for maize milk powder butter and rice imports in cyprus using annual time series data covering the period 1975 1994 none of these products is produced in cyprus and all the necessary quantities are imported to meet domestic demand the primary objective of the paper is to derive long run price and income elasticities of import demand that can be used to analyse the impact of various policies such as the adoption of the common agricultural policy cap when and if the republic of cyprus joins the european union eu in so doing the paper takes on board some recent developments in time series econometrics the cointegration test used the bounds test is a recent test and is based on the estimation of an unrestricted error correction model uecm parsimonious models were derived using hendry s general to specific approach the estimated elasticities were subsequently used to quantify some of the implications for cyprus had the cap been ope

the optimal tax on antebellum us cotton exports abstract the us produced about 80 of the world s cotton in the decades prior to the civil war how much monopoly power did the us possess in the world cotton market and what would have been the effect of an optimal export tax this paper estimates the elasticity of foreign demand for us cotton exports and uses the elasticity in a simple partial equilibrium model to calculate the optimal export tax and its effect on prices trade and welfare the results indicate that the export demand elasticity for us cotton was about 1 7 and that the optimal export tax of about 50 would have raised us welfare by about 10 million about 0 3 of us gdp or about 1 of the south s gdp

nonmonotonic demand for income redistribution benefits the case of afdc two different motives are often advanced to explain taxpayer nonrecipient support for income redistribution programs the first motive is the result of interdependent utilities between nonrecipients and the recipients of redistribution program benefits the source of this interdependence could be taxpayer altruism alternatively redistribution might be seen as one way to alleviate the potential for crime or social unrest recent theoretical analyses have suggested a second motiveincome redistribution programs act as protection against the possibility of unforseen loss in personal income 5 6 21 32 researchers using panel data find widespread random and temporary movements in individual income poverty and welfare program use that would seem to suggest a potentially significant insurance demand for redistribution programs 2 the results from one study for example indicate that while four to five percent of the total u s population could be classified as persistent recipients of welfare program benefits between 1969 and 1978 receiving program benefits in at least five of those years over one quarter of the u s population participated in welfare programs at least once over this same ten year period 9 74 in the past researchers estimating nonrecipient support for income transfer programs have considered only one of these two motives while ignoring the other 3 this paper extends the examination of the demand for income redistribution by integrating the public good and social insurance demand motives into one model the first part of the paper sets up the individual s decision model for income redistribution one consequence of interacting the public good and social insurance motives into one model is that support for higher benefit payments is expected to come from the tails of the income distribution low income individuals both recipients and nonrecipients benefit directly from the reduced risk of income randomness while high income

modeling international trade flows and market shares for agricultural commodities a modified armington procedure for rice abstract the armington procedure ap has become increasingly popular in agricultural trade analyses however some arguments have arisen concerning the relevance of using the procedure for such analyses this study examines the assumptions commonly made when using the armington procedure and suggests modifications for agricultural trade analyses results from models utilizing rice trade suggests that the assumptions of the single constant elasticity in particular may not be appropriate for analyzing trade these results also suggests that with proper modifications the ap can be applied to agricultural trade further results of a modified armington procedure indicate that trade in rice exports is highly competitive and that changes in market shares of individual exporters are not independent of changes in budget expenditure allocated to imports

the inverse almost ideal demand system abstract a new demand system related to the almost ideal demand system aids of deaton and muellbauer is developed and illustrated this inverse aids iaids retains all of the desirable theoretical properties of the aids model with the exception of consistent aggregation an empirical issue is whether a linear approximation will work as well for the iaids as it has for the aids model since quantities are not as highly correlated as prices an application to u s meat demand demonstrates that the linear approximation of the iaids is excellent which enhanced the ease and range of application

testing dynamic specification for import demand models the case of cotton error correction models impose few prior restrictions on dynamic model specification and allow the data to determine model structure despite this obvious advantage few applications have adopted the error correction model to explain trade flows an error correction model of cotton import demand is estimated for france japan and hongkong a variety of tests are applied to determine the dynamic structure of the model it is found that the most general models are those that best fit the data for cotton import demand long run elasticities from these general models are significantly different than elasticities derived from a comparable static model

analyzing the length of welfare spells abstract this paper studies the determinants of the length of individual spells of welfare focusing on how the length of a spell affects the probability of its termination the analysis utilizes six years of monthly data on time spent in the afdc program among female household heads a variety of duration dependence models are estimated monthly afdc participation does not show strong evidence of duration dependence two distinct groups appear to utilize welfare one with a very low and constant probability of leaving welfare and a second group which is more affected by time on the program

afdc benefits and the inter urban variation in poverty among female headed households the percentage of families headed by females in poverty varies widely across metropolitan areas for example 8 37 of all families in albany georgia were female headed and in poverty in 1980 while in sheboygan wisconsin the figure was 1 1 though not as dramatic as this interregional difference intra regional variation can also be significant in detroit michigan 4 90 of families were femaled headed and in poverty and in the closest interstate metropolitan area toledo ohio the figure was 3 77 recent research into the behavior of low income femaleheaded families suggests that state benefit differentials in aid to families with dependent children afdc may in part be responsible in this paper we construct a model that explains an important and overlooked implication of non uniform benefit standards among states the inter urban variation in the size of the potential and actual afdc recipient population particular attention is given to 1 the impact of interurban differences in real afdc payments 2 the potential of afdc to alter the number of female headed families in poverty and 3 the relative importance of other urban characteristics in explaining the size of the potential and actual afdc recipient population the model uses 1980 census data and is estimated for all standard metropolitan statistical areas for which we were able to obtain data

gender differences in observed and offered wages in canada 1980 according to the 1981 census of canada the female rate of pay is 30 percent less than the male rate the average female wage offer however is only around one half of that received by males other things being equal slightly more than one half of the difference in observed wages can be explained by diffe rences in wage related characteristics between males and females two fifths of the disparity between wage offers can be explained by the same set of factors analysis of the distribution of wage offers indicates greater wage inequality in the canadian labor market than suggested by study of observed wages

a two stage analysis of the effectiveness of promotion programs for u s apples export promotion programs are intended to help u s exporters enter maintain and expand foreign markets but little is known of their success in achieving each of these goals in this paper we attempt to determine the effectiveness of export promotion in increasing both u s market share and total import consumption using apple imports by singapore and the united kingdom as case studies estimates of a two stage linear expenditure system les almost ideal demand system aids model show that promotion increases consumption of apples in both the united kingdom and singapore but increases u s market share only in the united kingdom the results suggest that free riding on u s promotion can be significant

explaining armington what determines substitutability between home and foreign goods for decades trade economists have modeled imperfect substitution between home and foreign goods in consumption often called the armington assumption with little analysis of what explains the wide variation in these substitution elasticities across sectors using a varying coefficients model the authors estimate armington elasticities between u s domestic and foreign goods across over one hundred industrial sectors from 1980 to 1988 and examine the role of product industry political and home bias factors as determinants they find strong support that the presence of foreign owned affiliates affects armington elasticities in important ways and some support that entry barriers and union presence have an effect

a comparison of the effect of welfare programme features on welfare participation one and two parent families the effect of welfare programme characteristics on the decision to enter the welfare system is modelled as a binary discrete choice latent variable model dependent upon an underlying index function the two chief classes of welfare beneficiaries in the us welfare system are analysed two parent families and single female headed families the data set is a large recent non experimental multiyear cross sectional pooled data set derived from the us census bureaus current population survey behavioural impacts from a range of economic variables are consistent in sign with predictions made by economic theory newly estimated comprehensive descriptive statistics of the entire welfare system for both single female household heads and married couples with children are employed to characterize the welfare system statistically significant estimates of substantial magnitude are obtained for the impacts on welfare participation for the welfare guarantee level the effective tax rate on earned income and the effec

the 40 year pursuit of equal pay a case of constantly moving goalposts progress towards equal pay is elusive this article reviews debates on and prescribed remedies for gender pay equality over the past 40 years of equal pay policy it looks at pay from four perspectives the economic the sociological the institutional and the organisational and explores how and why once an apparent remedy for unequal pay is pursued the goalposts tend to shift the argument is made that the difficulties in securing long term progress may be attributed to a number of factors including the multifaceted nature of pay as a social phenomenon the challenge of pursuing social objectives in a rapidly changing and fragmenting environment the need for political will not technical solutions to achieve redistribution and the potential for gender inequalities to re emerge in new forms

the intergenerational transfer of welfare dependency some statistical evidence does a mother s welfare receipt increase the future dependency of her children does the welfare system thus stimulate the dependency of future generations parameter estimates reported here suggest such intergenerational effects the sample comprises young girls and their mothers after control for observed and unobserved heterogeneity a mother s welfare participation is found to increase her daughter s later welfare dependency copyright 1992 by mit press

food demand in rural china evidence from rural household survey abstract the recent rural reforms in china have had great effects on agricultural production and productivity as well as rural household consumption while much has been written on production and productivity effects of these reforms very few chinese studies have attempted to analyze the changes in rural consumption patterns this paper uses a dynamic aids model to estimate various food demand parameters for chinese rural households using rural household survey data recently released by the china state statistical bureau the results show that all important food commodities including rice wheat coarse grains vegetables meat tobacco and alcohol have positive expenditure elasticities rice wheat and coarse grains are necessities while meat vegetables alcohol and tobacco are luxuries the expenditure elasticities for rice coarse grains and tobacco are declining but those for wheat meat vegetables and alcohol are increasing as per capita income rises and population increases the demand for these items will continue to increase therefore china must continue to increase its food production by a greater rate in the future in order to avoid food shortages

product aggregation bias as a specification error in demand systems inherent in all demand studies is some form of product aggregation which can lead to product aggregation bias this article develops a simple procedure for incorporating product aggregation bias in demand systems that permits testing of product aggregation bias with a standard likelihood ratio test an empirical illustration of the procedure demonstrates the importance of proper product aggregation

multilateral agricultural trade liberalisation the contrasting fortunes of developing countries in the doha round an applied general equilibrium model is used to assess the impact of multilateral trade liberalisation in agriculture with particular emphasis on developing countries we use original data and the model includes some specific features such as a dual labour market applied tariffs including those under preferential regimes and regional agreements are taken into account at the detailed product level together with the corresponding bound tariffs on which countries negotiate the various types of farm support are detailed and several groups of developing countries are distinguished simulations give a contrasted picture of the benefits developing countries would draw from the doha development round the results suggest that previous studies have neglected preferential agreements and the binding overhang in tariffs as well as domestic support and have treated developing countries with a high level of aggregation and been excessively optimistic about the actual benefits of multilateral trade liberalisation regions like sub saharan africa are more likely to suffer from the erosion of existing preferences the main gainers of the doha round are likely to be developed countries and cairns group members

male female wage differentials and policy responses without implicating them for any of the contents of the paper i am grateful to the following for helpful discussions or comments andrea beller university of illinois david bloom harvard and columnbia glen cain university of wisconsin ron ehrenberg cornell victor fuchs stanford bob gregory australian national university jonathan leonard university of california berkeley roberta robb brock university and paul weiler harvard financial support of the humanities and social sciences committee of the research board of the universitu of toronto is eratefullu acknowlede ed

homothetic efficiency theory and applications we provide a nonparametric revealed preference approach to demand analysis based on homothetic efficiency homotheticity is widely assumed often implicitly because it is a convenient and often useful restriction however this assumption is rarely tested and data rarely satisfy testable conditions to overcome this we provide a way to estimate homothetic efficiency of consumption choices the method provides considerably higher discriminatory power against random behavior than the commonly used afriat efficiency we use experimental and household survey data to illustrate how our approach is useful for different empirical applications and can provide greater predictive success

effective tax rates and guarantees in the afdc program 1967 1982 estimates of effective tax rates on earned and unearned income and estimates of effective guarantees in the afdc program by state are provided for the period 1967 1982 the results indicate that effective real guarantees fell every year from 1967 to 1981 but stabilized in 1982 effective tax rates on unearned income rose steadily from 1967 to 1981 and took a particularly large additional jump in 1982 effective tax rates on earned income fell after 1967 but then gradually rose throughout the 1970s until 1982 when they took a much larger jump thus guarantees fell and tax rates rose over the 1970s as tight budgets forced states to restrict benefits and in the early 1980s tax rates were pushed even higher by federal legislation

elasticities in aids models in the literature a variety of approaches have been used to calculate demand elasticities in almost ideal demand system aids models of demand it is common to estimate the linear approximate almost ideal demand system la aids instead of the aids when the la aids is estimated all of the previously reported approaches to compute elasticities are theoretically incorrect this paper presents correct formulas for la aids elasticities and illustrates the potential errors from using incorrect computing the almost ideal demand system aids of deaton and muellbauer 1980a b has become popular in recent years anderson and blundell blanciforti and green 1983a b blanciforti green and king chalfant eales and unnevehr fujii khaled and mak fulponi heien and willett murray parsons ray a variety of approaches to computing elasticities has been used and some of the approaches may lead to significant errors this paper clarifies the differences between alternative approaches to estimating demand elasticities in aids models

non stationarity and the import demand for virgin olive oil in the european union the aim of this study is to analyse the importation of virgin olive oil to european union countries paying special attention to the spanish export contribution the method used is based on the estimation of an imports demand system the novelty of the paper lies not in the modelling approach but in the explicit consideration of the univariate characteristics of series that is included in the analysis since prices are non stationary cointegration among them has been tested results indicate that they are cointegrated and that homogeneity holds as a result relative prices are included in the imports demand system structural change is also considered so as to account for the entrance of both spain and greece into the eu during the period studied results demonstrate the leadership of spain within the eu virgin olive oil market as well as the increasing competitiveness of greek oil

accounting for changes in tastes health concerns are thought by many to have shifted consumption away from red meats though econometric evidence is mixed testing for structural change is difficult especially when one time series is used for both estimating demand equations and testing their stability specification errors may suggest a shift where none has occurred using nonparametric demand analysis we find that meat consumption patterns in the united states and australia can be explained using only relative prices and expenditures only imposing particular functional forms can reverse the conclusion suggesting that specification errors in econometric demand studies can account for findings of taste changes

labour supply impacts of effective welfare programme parameters a reanalysis we quantify the impact of effective welfare programme parameters on the labour supply of single female household heads the primary group of welfare recipients in the usa our panel of data is derived from the us census bureau s current population survey for the years 1979 to 1990 inclusive behavioural impacts from a range of economic variables are consistent in sign with predictions made by economic theory we find that effective welfare gurantee levels and the effective tax rate on earned income both significantly decrease labour supply the marginal effects of these welfare programme parameters are economically small a us 1000 increase in the expected welfare guarantee level reduces annual labour supply by about 36 hours a 10 percentage point increase in the effective tax rate on earned income reduces annual labour supply by about 7 5 hours

whither armington trade models the armington trade model distinguishes commodities by country of origin and import demand is determined in a separable two step procedure this framework has been applied to numerous international agricultural markets with the objective of modeling import demand in addition computable general equilibrium cge models commonly employ the armington formulation in the trade linkage equations the purpose of this paper is to test the armington assumptions of homotheticity and separability with data from the international cotton and wheat markets both parametric and nonparametric tests were performed and the empirical results reject the armington assumptions this has important implications for international trade modeling and cge modeling

child support welfare dependency and poverty female headed families have among the highest poverty rates of any major demographic group in the united states the purpose of this paperis to investigate empirically the effectiveness of current child support enforcement policies and to determine their role in reducing poverty and welfare dependency a special supplement to the april 1982 current population survey provides the data for the analysis the results indicate that child support enforce ment may represent an effective means for re ducing welfare program costs but isunlikely to have a dramatic effect on either welfare de pendency or poverty copyright 1986 by american economic association

incorporating the causes of occupational differences in studies of racial wage differentials this study provides a basic framework for incorporating the causes of occupational differences into analyses of racial wage differentials separating the influences of personal characteristics occupational choice and hiring discrimination on occupational attainment provides measures of the contributions of each to the racial pay gap the paper also considers the potential for bias in the wage equation estimates arising from self selection into occupations there are two generalfindings first correcting for self selection increases the importance of occupational distribution in explaining racial wage differentials second a proper accounting of the causes of these occupational differences yields discrimination measures that are higher than those that arise when occupational dummy variables are included in the wage equations and all the difference in occupational distribution is treated as nondiscriminatory

estimating a dynamic model of household choices in the presence of income taxation the purpose of the article is to study the incentive and distributional consequences of income taxation the article analyzes tax changes in a dynamic setting the framework is estimated under a set of different identifying assumptions using parametric nonparametric and semiparametric techniques the empirical results focus on tax reforms in germany in the 1980s the article shows that these reforms did not significantly lower effective tax rates the findings also suggest that estimated elasticities for male labor supply are small ranging between 0 02 and 0 2

meta analysis of general and partial equilibrium simulations of doha round outcomes quantification of welfare changes due to trade liberalization plays a crucial role for political decision making however significant differences in simulated gains from liberalization do not serve to increase confidence in quantitative assessments based on trade models a meta analysis of trade simulations under the wto doha round is employed to identify model characteristics that influence the magnitude of simulation results findings from a simple regression model are plausible and show that each simulation experiment represents a complex interaction of model characteristics and experimental settings that may not easily be communicated to nonexperts meta analysis proves to be useful for empirically assessing this complexity

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welfare the earned income tax credit and the labor supply of single mothers during 1984 1996 welfare and tax policy were changed to encourage work by single mothers the earned income tax credit was expanded welfare benets were cut welfare time limits were added and welfare cases were terminated medicaid for the working poor was expanded as were training programs and child care during this same time period there were unprecedented increases in the employment and hours of single mothers we show that a large share of the increase in work by single mothers can be attributed to the eitc and other tax changes with smaller shares for welfare benet cuts welfare waivers training programs and child care programs