doubly robust estimation of causal effects with multivalued treatments an application to the returns to schooling summary this paper provides doubly robust estimators for treatment effect parameters which are defined in a multivalued treatment effect framework we apply this method to the unique dataset of the 1970 british cohort study bcs70 to estimate returns to various levels of schooling the analysis is carried out for female and male samples separately to capture possible gender differences average returns are estimated for the entire population as well as conditional on having a specific educational achievement for males relative to no qualification we find an average return to o levels of 6 3 to a levels of 7 9 and to higher education of 25 4 the estimated average returns to o level and a level relative to no qualification are insignificant for females whereas the return to higher education is 19 9 copyright 2014 john wiley sons ltd

smallholders land access in sub saharan africa a new landscape while scholars long recognized the importance of land markets as a key driver of rural non farm development and transformation in rural areas evidence on the extent of their operation and the nature of participants remains limited we use household data from 6 countries to show that there is great potential for such markets to increase productivity and equalize factor ratios while rental markets transfer land to land poor and labor rich producers their operation and thus impact may be constrained by policy restrictions their functioning may also be constrained by ill defined or insecure rights that may arise from failure to fully compensate existing rights in cases of expropriation a failure to implement more broadly land policies or to do so in a gender sensitive manner methodological and substantive conclusions are derived

eradicating diseases the effect of conditional cash transfers on vaccination coverage in rural nicaragua despite significant global efforts to improve vaccination coverage against major childhood diseases vaccination rates are below 90 to eradicate diseases such as measles however vaccination rates close to 95 are needed we use a randomized experiment to investigate the effect of a demand incentive a conditional cash transfer program in improving vaccination coverage in rural nicaragua double difference estimates show the program led to large increases in vaccination coverage and these resulted in vaccination levels greater than 95 for some vaccines effects were especially large for children who are typically harder to reach with traditional supply side interventions

urbanization and poverty reduction the role of rural diversification and secondary towns a rather unique panel tracking more than 3 300 individuals from households in rural kagera tanzania during 1991 4 2010 shows that about one in two individuals households who exited poverty did so by transitioning from agriculture into the rural nonfarm economy or secondary towns only one in seven exited poverty by migrating to a large city although those moving to a city experienced on average faster consumption growth further analysis of a much larger cross country panel of 51 developing countries cannot reject that rural diversification and secondary town development lead to more inclusive growth patterns than metropolitization indications are that this follows because more of the poor find their way to the rural nonfarm economy and secondary towns than to distant cities the development discourse would benefit from shifting beyond the rural urban dichotomy and focusing instead more on how best to urbanize and develop the rural nonfarm economy and secondary towns

the long run effects of unemployment monitoring and work search programs experimental evidence from the united kingdom this article examines the long run effects of the restart unemployment program in the united kingdom the program aimed at the long term unemployed involved a combination of tighter monitoring of benefit eligibility rules and increased job search assistance we compare the employment behavior of a treatment group who participated in the scheme with that of a randomly chosen control group for whom participation was delayed while there is little evidence of a long term benefit for women the unemployment rate among males in the treatment group was six percentage points lower than that of the control group 5 years after the initial experiment

the microfinance promise in the past decade microfinance programs have demonstrated that it is possible to lend to low income households while maintaining high repayment rates even without requiring collateral the programs promise a revolution in approaches to alleviating poverty and spreading financial services and millions of poor households are served globally a growing body of economic theory demonstrates how new contractual forms offer a key to microfinance success particularly the use of group lending contracts with joint liability for the most part however high repayment rates have not translated into profits and studies of impacts on poverty yield a mixed picture in describing emerging tensions the paper highlights the diversity of innovative mechanisms beyond group lending contracts the measurement of financial sustainability the estimation of economic and social impacts the costs and benefits of subsidization and the potential to reduce poverty through savings programs rather than just credit the promise of microfinance has pushed far ahead of the evidence and an agenda is put forward for addressing critical empirical gaps and sharpening the terms of policy discussion

do better schools matter parental valuation of elementary education the evaluation of numerous school reforms requires an understanding of the value of better schools given the difficulty of calculating the relationship between school quality and student outcomes i turn to another method and use house prices to infer the value parents place on school quality i look within school districts at houses located on attendance district boundaries houses then differ only by the elementary school the child attends i thereby effectively remove the variation in neighborhoods taxes and school spending i find that parents are willing to pay 2 5 percent more for a 5 percent increase in test scores this finding is robust to a number of sensitivity checks

a reanalyis of marital stability in the seattle denver income maintenance experiment this paper challenges the widely cited finding of groeneveld hannan and tuma that the seattle denver income maintenance experiment provides evidence that guaranteed income plans for poor husband wife families will increase marital dissolution relative to the existing program aid to families with dependent children the reanalysis of the experimental data distinguishes between the experimental treatment in the form of the pure negative income tax and the treatment plans that involved an experimental training program all the time periods of the experiment are used with allowance for the timing of the marital dissolution in the inferences and with allowance for attrition the conclusion of this paper is that the plans specifically the negative income tax plans in the experiment had no effect on the rate of marital dissolutions among the treatment couples relative to the control couples

using maimonides rule to estimate the effect of class size on scholastic achievement the twelfth century rabbinic scholar maimonides proposed a maximum class size of 40 this same maximum induces a nonlinear and nonmonotonic relationship between grade enrollment and class size in israeli public schools today maimonides rule of 40 is used here to construct instrumental variables estimates of effects of class size on test scores the resulting identiecation strategy can be viewed as an application of donald campbell s regression discontinuity design to the class size question the estimates show that reducing class size induces a signiecant and substantial increase in test scores for fourth and efth graders although not for third graders when asked about their views on class size in surveys parents and teachers generally report that they prefer smaller classes this may be because those involved with teaching believe that smaller classes promote student learning or simply because smaller classes offer a more pleasant environment for the pupils and teachers who are in them mueller chase and walden 1988 social scientists and school administrators also have a longstanding interest in the class size question class size is often thought to be easier to manipulate than other school inputs and it is a variable at the heart of policy debates on school quality and the allocation of school resources in many countries see e g robinson 1990 for the united states ofsted 1995 for the united kingdom and moshel ravid 1995 for israel this broad interest in the consequences of changing class size

employment dynamics in the rural nonfarm sector in ethiopia do the poor have time on their side abstract we study rural employment transitions in ethiopia between farming and both low and high return nonfarm employment we find that initial asset holdings and access to saving and credit are important factors for transition into high return rural nonfarm employment and that households participation in high return rural nonfarm activities is robust to their experience of health shocks however shocks that affect their wealth or liquidity may trigger descents into low return nonfarm employment on the other hand shocks that reduce agricultural income motivate transitions into high return rural nonfarm employment

evaluating social policy by experimental and nonexperimental methods although it is important to establish causal relationships in social policy evaluation the effects are difficult to observe due to sample selection to evaluate the performance of estimators designed to handle sample selection bias we analyse data from a norwegian rehabilitation project with a randomised experimental design the data permit us to compare the performance of different nonexperimental estimators with the experimental results in our case study we find that nonexperimental evaluation based on sample selection estimators with selection terms that fail to meet conventional levels of statistical significance is highly unreliable the difference in difference estimator and propensity score matching estimators perform better in our context jel classification c51 j24 h43 i12

assessing the case for social experiments rs ecent academic debates pit two alternative approaches to policy evaluation against one another the first is the experimental approach based on the random assignment of accepted program applicants to a recipient or treatment group and a non recipient or control group the second is the nonexperimental or econometric approach that uses a variety of microdata sources statistical methods and behavioral models to compare the outcomes of participants in social programs with those of nonparticipants the central question addressed in this paper is whether or not randomized social experiments aid in securing answers to basic questions about the evaluation of social programs there are many distinct and complementary approaches to the study of the impact of public policy including full general equilibrium analysis of policy impacts tinbergen 1956 auerbach and kotlikoff 1987 shoven and whalley 1992 kydland and prescott 1991 and less ambitious partial equilibrium microeconomic structural research programs such as those designed to estimate the impact of taxes on labor supply both approaches offer answers to many interesting counterfactual policy questions but their credibility rests critically on the quality of the empirical input used to generate their answers

a cross country comparison of rural income generating activities summary this paper uses a newly constructed cross country database composed of comparable income aggregates to examine the full range of income generating activities carried out by rural households the analysis paints a clear picture of multiple activities across rural space in countries on all four continents though less so in the included african countries for most countries the largest share of income stems from off farm activities and the largest share of households has diversified sources of income diversification not specialization is the norm nevertheless agricultural sources of income remain critically important for rural livelihoods in all countries

nonfarm income diversification and household livelihood strategies in rural africa concepts dynamics and policy implications abstract asset activity and income diversification lie at the heart of livelihood strategies in rural africa this paper introduces a special issue on the topic income diversification and livelihoods in rural africa cause and consequence of change we concentrate on core conceptual issues that bedevil the literature on rural income diversification and the policy implications of the empirical evidence presented in this special issue

programme evaluation with multiple treatments this paper reviews the main identification and estimation strategies for microeconometric policy evaluation particular emphasis is laid on evaluating policies consisting of multiple programmes which is of high relevance in practice for example active labour market policies may consist of different training programmes employment programmes and wage subsidies similarly sickness rehabilitation policies often offer different vocational as well as non vocational rehabilitation measures first the main identification strategies control for confounding variables difference in difference instrumental variable and regression discontinuity identification are discussed in the multiple programme setting thereafter the different nonparametric matching and weighting estimators of the average treatment effects and their properties are examined download discussion paper pdf 484 kb

the effectiveness of active labour market policies a meta analysis this paper provides a meta analysis of microeconometric evaluation studies on the effectiveness of active labor market policies the analysis is built upon a systematically assembled data set of causal impact estimates from 57 experimental and quasi experimental studies providing 654 estimates published between january 1990 and december 2017 we distinguish between the short and longer term impacts in our analysis at 6 12 24 and 36 months after program start after correcting for publication bias and country specific macroeconomic characteristics subsidized labor and public employment programs have negative short term impacts which gradually turn positive in the longer run schemes with enhanced services including job search assistance and training programs do not have these negative short term effects and stay positive from 6 until 36 months after program start

going green does it depend on education gender or income sustainable development entails meeting our present needs without compromising the ability of future generations to meet their needs this requires us to treat economic social and environmental aspects in an integrated way but little is known about the nature of individual preferences towards the trade offs involved in this effort for the first time we study individual preferences towards the environment social well being and financial well being by using a survey of over 1400 households in the netherlands using nonparametric parametric and matching methods we find that gender and education are important factors for sustainability rather than income levels moreover results indicate that educated females put the greatest value on going green whilst being socially minded

monotone instrumental variables with an application to the returns to schooling for fifty years econometric analyses of treatment response have made extensive use of instrumental variable iv assumptions holding that mean response is constant across specified subpopulations of a population of interest 2 yet the credibility of mean independence conditions and other iv assumptions has often been a matter of considerable disagreement with much debate about whether some covariate is or is not a valid instrument in an application of interest there is therefore good reason to consider weaker but more credible assumptions to this end we introduce monotone instlumental variable miv assumptions holding that mean response varies weakly monotonically across specified subpopulations we study the identifying power of these miv assumptions and give an empirical application the findings reported here add to the literature developing nonparametric bounds on treatment effects 3 this paper uses the same formal setup as manski 1997 there is a probability space j x2 p of individuals each member j of population j has observable covariates xi e x and a response function yj t y mapping the mutually exclusive and exhaustive treatments t e t into outcomes yj t e y person j has a realized treatment zj e t and a realized outcome y 1 y zi both of which are observable the latent outcomes yj t

effectiveness of sequences of one euro jobs for welfare recipients in germany empirical evidence reveals that german welfare recipients often participate in multiple active labour market programmes almps however evidence on the effectiveness of almps exists mostly for single almp participations so far this article evaluates the sequential participation in almps for welfare recipients in germany based on comprehensive administrative data to control for dynamic selection that arises in the evaluation of sequences using a dynamic causal model and an inflow sample of welfare recipients the article analyses the effects of sequences of a public employment programme called one euro jobs on labour market outcomes for female participants in one euro jobs in the first period especially in west germany the results imply that participating in two consecutive one euro jobs compared with receiving only welfare benefits for two consecutive periods better facilitates integration into regular employment moreover taking part in a one euro job directly after entry into welfare receipt is

agriculture in africa telling myths from facts a synthesis stylized facts drive research agendas and policy debates yet robust stylized facts are hard to come by and when available often outdated in a special issue of food policy 12 papers revisit conventional wisdom on african agriculture and its farmers livelihoods using nationally representative surveys from the living standards measurement study integrated surveys on agriculture initiative in six african countries at times the findings simply confirm the common understanding of the topic but the studies also throw up several surprises redirecting some policy debates while fine tuning others overall the project calls for more attention to checking and updating the common wisdom this requires nationally representative data and sufficient incentives among researchers and policy makers alike without well grounded stylized facts they can easily be profoundly misguided

the econometrics of the general equilibrium approach to business cycles early in this century american institutionists and members of the german historical school attacked and rightfully so neoclassical economic theory for not being quantitative this deficiency bothered ragnar frisch and motivated him along with irving fisher joseph schumpeter and others to organize the econometric society in 1930 the aim of the society was to foster the development of quantitative economic theory that is the development of what frisch labeled econometrics soon after its inception the society started the journal econometrica frisch was the journal s first editor and served in this capacity for twenty five years

securitization and bank performance theory suggests that securitization provides financial institutions with an opportunity to lower the cost of funding improve credit risk management and increase profitability in practice however it might lead to adverse consequences through a number of indirect channels therefore the net impact of securitization on bank performance is ambiguous this study aims to evaluate whether banks improve their performance through the use of the securitization market by applying a propensity score matching approach in other words we build a counterfactual group of banks to assess what would have happened to the securitizing banks had they not securitized using us commercial banking data from 2001 to 2008 we first test these hypotheses using univariate analysis and find that securitizing banks are on average more profitable institutions with higher credit risk exposure and higher cost of funding however the propensity score matching analysis does not provide evidence of significant causal effects of securitization on the performance of banks therefore securitization does not seem to outperform alternative funding risk management and profitability improvement techniques used by banks that have ex ante similar characteristics to those securitizing our evidence raises important questions about the motives for banks increasing securitization activities and consequent implications for the banking system

lifetime earnings and the vietnam era draft lottery evidence from social security administrative records errata the randomly assigned risk of induction generated by the draft lottery is used to construct estimates of the effect of veteran status on civilian earnings these estimates are not biased by the fact that certain types of men are more likely than others to service in the military social security administrative records indicate that in the early 1980s long after their service in vietnam had ended the earnings of white veterans were approximately 15 percent less than the earnings of comparable nonveterans copyright 1990 by american economic association

the pre programme earnings dip and the determinants of participation in a social programme implications for simple programme evaluation strategies the key to estimating the impact of a programme is constructing the counterfactual outcome representing what would have happened in its absence this problem becomes more complicated when agents such as individuals firms or local governments self select into the programme rather than being exogenously assigned to it this paper uses data from a major social experiment to identify what would have happened to the earnings of self selected participants in a job training programme had they not participated in it we investigate the implications of these earnings patterns for the validity of widely used before after and difference in differences estimators

does the nonfarm economy offer pathways for upward mobility evidence from a panel data study in ethiopia summary empirical studies across many developing countries routinely document a positive correlation between participation in rural nonfarm employment and households wealth or income this paper explores whether nonfarm employment leads to higher consumption expenditure growth in ethiopia we find that 1 households consumption expenditure growth is positively correlated with the initial share of nonfarm income 2 the growth elasticity of nonfarm income share is higher for wealthier households and 3 the main source of growth for nonfarm participants comes from the higher rates of return participants enjoy on their human and physical capital

the associations of soil fertility and market access with household income evidence from rural uganda abstract this study attempts to identify the major factors affecting farm and nonfarm income by using panel data of 894 rural households interviewed in 2003 and 2005 in rural uganda we supplement the panel data with household level soil fertility data and road distance data to the nearest urban center on three road types tarmac loose surface and dirt roads the results suggest that soil fertility measured by the soil organic matter som content is positively associated with crop income but not with livestock and nonfarm income we also find that the total road distance to the nearest urban center and the road quality have strong negative associations with the crop income

a model based assessment of the impact of revitalised r d investments on the european power sector abstract this paper presents an analysis of the effect of enhanced research and development r d efforts for a set of low carbon power technologies on the development of the european energy sector it applies a methodology using the concept of two factor learning which quantitatively links trends in technology cost to both accumulated r d investments and production volumes the impacts of the latter on the energy sector are then simulated in a consistent manner with the poles global energy model on this basis it compares the total system costs of an assumed increase in worldwide r d investments that for the eu are in line with proposals made in its european strategic energy technology plan to a baseline development it finds that an increase in research efforts at a global level will contribute to reducing the costs of currently less mature low carbon technologies thus accelerating their market entry when comparing two scenarios that both fulfil the eu s 2020 energy and climate objectives and differing only in their r d investment levels the reduced technology costs allow eu support policies for renewables and carbon values to be reduced and the cumulative discounted benefit of the accelerated research efforts is positive in the long term

agriculture structural transformation and poverty reduction eight new insights abstract whether the sector of growth matters for the speed of poverty reduction why and how best to invest to maximize the poverty reducing effects of sectoral growth remain topics of intense debate drawing on the more recent history and applying a range of methods the papers in this special issue confirm the view that growth in agriculture is on average more poverty reducing than an equivalent amount of growth outside agriculture they also add important nuances to this broad empirical regularity uncover a series of structural conditions that affect this relation and show that different mechanisms to finance public investment to boost sectoral growth deficit financing taxation or aid can have widely different impacts on poverty a widely ignored issue so far they do so by going beyond the traditional agriculture nonagriculture dichotomy also looking at the subsectors and the differential effects of prices versus productivity they further distinguish between production for home and market consumption between modern outward oriented and informal domestically focused firms as well as between secondary towns and cities eight key insights emerge

courses or individual counselling does job search assistance work how does labour market policy affect welfare recipients and long term unemployed people we investigate whether job search assistance jsa helps disadvantaged individuals to find jobs and whether courses or individual counselling is more successful in reaching this goal to evaluate individual employment effects we apply a quasi experimental design and construct suitable comparison groups using propensity score matching methods we compare participants to nonparticipants as well as participants of both schemes directly our article benefits from access to rich administrative data from the german federal employment agency when comparing participants to nonparticipants results suggest that the individual jsa does not affect participants employment prospects at all and that the course jsa even decreased their employment chances at the same time differences in these effects can be ascribed to programme design differences and to differences in the groups of participants therefore we compare both progr

earnings and employment effects of continuous off the job training in east germany after unification the effects of continuous off the job training oft for east germans after unification are analyzed in terms of their earnings and employment probabilities using the potential outcome approach to causality as general framework different matching procedures are suggested for the estimation they allow for permanent and transitory shocks that influence oft participation and labor market outcomes the matching procedures also take account of individually different starting dates the data are taken from the german socio economic panel gsoep 1990 1994 this dataset is very informative with respect to factors influencing the participation in training the results show no positive effects of training

evaluation of swedish youth labor market programs this paper evaluates two swedish active labour market programmes for youth namely youth practice and labour market training a non parametric matching approach is applied to estimate the average p

evaluating the econometric evaluations of training programs with experimental data this paper takes the results of an employment and training program thatwas run as a field experiment in which the participants were randomlyassigned into a treatment or a control group and compares these results to the estimates that might have been produced by an econometrician who evaluated the program using the same econometric procedures that have been used in the program evaluation literature this comparison shows that many of these econometric procedures fail toreplicate the experimentally determined results and suggests that researchers should be aware of the potential for specification errorsin other nonexperimental evaluations copyright 1986 by american economic association

technological learning in energy environment economy modelling a survey abstract this paper aims at providing an overview and a critical analysis of the technological learning concept and its incorporation in energy environment economy models a special emphasis is put on surveying and discussing through the so called learning curve both studies estimating learning rates in the energy field and studies incorporating endogenous technological learning in bottom up and top down models the survey of learning rate estimations gives special attention to interpreting and explaining the sources of variability of estimated rates which is shown to be mainly inherent in r d expenditures the problem of omitted variable bias the endogeneity relationship and the role of spillovers large scale models survey show that despite some methodological and computational complexity related to the non linearity and the non convexity associated with the learning curve incorporation results of the numerous modelling experiments give several new insights with regard to the analysis of the prospects of specific technological options and their cost decrease potential bottom up models and with regard to the analysis of strategic considerations especially inherent in the innovation and energy diffusion process in particular the energy sector s endogenous responses to environment policy instruments top down models

effectiveness of one euro jobs do programme characteristics matter recent german labour market reforms introduced a large scale workfare programme called one euro jobs to activate welfare recipients and improve their employment prospects in programme design leeway is left to regional actors using administrative data and propensity score ps matching this article investigates the association between programme design and effectiveness so as to provide insight on how to increase programme effectiveness first effects of different types of one euro jobs according to planned duration and weekly working hours compared to waiting are estimated second programme types are compared directly to disentangle selection and programme effects as expected lock in effects are larger for participations with a longer planned duration but not for those with longer weekly working hours one euro jobs do not generally increase the employment prospects for east german men beyond 2 years after programme start and longer and more intensive participations even decrease employment prosp

matching as a tool to decompose wage gaps abstract this paper presents a methodology that uses matching comparisons to explain gender wage differences the approach emphasizes gender differences in the supports of the distributions of observable characteristics and provides insights into the distribution of unexplained gender pay differences this nonparametric alternative to the blinder oaxaca bo decomposition does not require the estimation of earnings equations and divides the gap into four additive elements two of these are analogous to the elements of the bo decomposition but computed only over the common support of the distributions of characteristics while the other two account for differences in the supports

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

saving taxes through foreign plant ownership this paper analyzes to which extent foreign plant ownership involves lower tax payments than domestic plant ownership we employ a model of endogenous foreign subsidiary ownership to derive a set of empirically testable hypotheses about the differential taxation of foreign and domestically owned subsidiaries we assess these hypotheses in a data set of 33 577 european foreign and domestically owned manufacturing plants we identify a significant tax saving of endogenous foreign owner ship on average foreign owners pay 594 euros per employee or about 56 percent less than domestic owners of similar subsidiaries this effect is larger in thinner markets with fewer plants in markets with a greater relative presence of foreign owners and for foreign owners of larger plants

a microeconometric evaluation of rehabilitation of long term sickness in sweden in this study the effects of various types of rehabilitation programmes on labour market out comes are estimated a main feature of this study is that it jointly evaluates multiple treat ments by nonparametric matching estimators the study is based on a large sample of per sons in western sweden who are long term sick and could participate in rehabilitation pro grammes our results suggest that work place training is superior to the other rehabilitation programmes with respect to labour market outcomes but compared to non participation no positive effects are found doi 10 1002 jae 757 download appendix pdf 147 kb

the rural non farm sector issues and evidence from developing countries abstract the rural non farm sector has traditionally been viewed as a low productivity sector which produces low quality goods it is often expected to wither away as a country develops recent years have seen a shift away from this position towards recognition that the rural non farm sector can and often does contribute to economic growth rural employment poverty reduction and a more spatially balanced population distribution this paper reviews the literature on the conceptual and empirical underpinnings of this more recent perspective focussing on the experience in developing countries the paper documents the size and heterogeneity of the sector pointing to evidence that in many countries the sector is expanding rather than declining the issues associated with measuring the sector s economic contribution are discussed followed by empirical assessments for several countries and regions the distributional impact of non farm earnings is examined and it is found that a pro poor impact while by no means inevitable can be considerable the sector s trajectory over time in different settings is reviewed and the scope for and experience of various policy interventions is discussed

non cognitive child outcomes and universal high quality child care exploiting a rich panel data child survey merged with administrative records along with a pseudo experiment generating variation in the take up of pre school across municipalities we provide evidence of the effects on non cognitive child outcomes of participating in large scale publicly provided universal pre school programs and family day care vis a vis home care we find that compared to home care being enrolled in pre school at age three does not lead to significant differences in child outcomes at age seven no matter the gender or mother s level of education family day care on the other hand seems to significantly deteriorate outcomes for boys whose mothers have a lower level of education finally increasing hours in family day care from 30 40 hours per week to 40 50 hours per week and hours in pre school from 20 30 hours per week to 30 40 hours per week leads to significantly poorer child outcomes

agriculture in the process of development a micro perspective abstract this paper compares national level data from india with 40 years of household panel data from rural india to track sectoral changes in employment and income as well as examine the hypothesis of induced innovation in agricultural production in the national data india appears to be in the midst of a structural transformation the share of agriculture in gdp and employment has shrunk while agricultural output continues to grow this productivity growth appears to adhere to the induced innovation hypothesis as productivity per hectare has increased more rapidly than productivity per worker many of the same patterns exist in the household data tracking households across time i observe agricultural output has increased despite more households engaging in off farm labor household agricultural production is highly specialized and has increased its reliance on improved inputs however while agricultural income has grown industrial and service income has remained stagnant and the relative income of these households has declined in recent years

the impact of r d on innovation for wind energy in denmark germany and the united kingdom this paper examines the impact of public research and development r d support on cost reducing innovation for wind turbine farms in denmark germany and the united kingdom uk first we survey the literature in this field the literature indicates that in denmark r d policy has been more successful than in germany or the uk in promoting innovation of wind turbines furthermore such studies point out that subsidy induced capacity expansions were more effective in the uk and denmark in promoting cost reducing innovation than in germany the second part of the paper describes the quantitative analysis of the impact of r d and capacity expansion on innovation this is calculated using the two factor learning curve 2flc model in which investment cost reductions are explained by cumulative capacity and the r d based knowledge stock time series data were collected for the three countries and organized as a panel data set the parameters of the 2flc model were estimated focusing on the homogeneity and heterogeneity of the parameters across countries we arrived at robust estimations of a learning by doing rate of 5 4 and a learning by searching rate of 12 6 the analysis underlines the homogeneity of the learning parameters enhancing the validity of the 2flc formulation

are african households not leaving agriculture patterns of households income sources in rural sub saharan africa this paper uses comparable income aggregates from 41 national household surveys from 22 countries to explore the patterns of income generation among rural households in sub saharan africa and to compare household income strategies in sub saharan africa with those in other regions the paper seeks to understand how geography drives these strategies focusing on the role of agricultural potential and distance to urban areas specialization in on farm activities continues to be the norm in rural africa practiced by 52 percent of households as opposed to 21 percent of households in other regions regardless of distance and integration in the urban context when agro climatic conditions are favorable farming remains the occupation of choice for most households in the african countries for which the study has geographically explicit information however the paper finds no evidence that african households are on a different trajectory than households in other regions in terms of transitioning to non agricultural based income strategies

estimating the benefit incidence of an antipoverty program by propensity score matching this brief summarizes the results of a gender impact evaluation study entitled estimating the benefit incidence of an antipoverty program by propensity score matching conducted between 1997 and 1998 in argentina the study observed that the average direct gain to the participant is found to be about half the gross wage over half of the beneficiaries are in the poorest decile nationally and 80 percent are in the poorest quintile the propensity score matching psm estimator is reasonably robust to a number of changes in methodology participants are more likely to be poor than non participants participants are less well educated live in poorer neighborhoods and are more likely to be members of neighborhood associations and political parties average gains are similar between men and women but are higher for younger workers funding for the study derives from the world bank research committee

smallholder participation in vegetable exports and age disaggregated labor allocation in northern tanzania modern agricultural supply chains have been playing an increasingly important role in developing countries and have had significant effects on rural labor markets this article analyses the effects of smallholder farmer participation in export vegetable supply chains in northern tanzania on both household hired labor demand and off farm labor supply using an age disaggregated approach in our sample neither separability nor exogeneity of smallholder farmer participation in export supply chains can be rejected hence we apply lognormal double hurdle models and find that participation in export supply chains positively affects households decision to hire labor from all age groups we also find that it increases the unconditional overall level of hired labor demand while the age disaggregated analysis shows that these effects mostly benefit rural youth however our sample does not allow us to establish statistically significant evidence of an effect on household off farm labor supply although the point estimates point to nonnegligible positive effect sizes

the effect of separation bonuses on voluntary quits evidence from the military s downsizing this paper analyzes the decision of mid career personnel to voluntarily leave the u s military in response to a financial incentive program a model of the separation decision is tested using data on navy and air force enlisted personnel who were targeted for the buyout in 1992 two alternative estimates are provided one from a fixed effects model and one from a structural annualized cost of leaving model our basic results indicate the financial incentive had a modest effect in inducing additional quits the impact of the separation bonus however was much larger for occupations facing a threat of involuntary layoff

endogenous technological change and the policy mix in renewable power generation abstract this paper introduces the renewable power generation module which complements large scale macro econometric input output models by introducing technological change endogenously into the model so far technological change in renewable power generation technologies is either set exogenously autonomous energy improving technological change or price induced in economic models introducing endogenous technological change is necessary to adequately analyze not only the direct effects but also the indirect effects on important macro economic indicators such as growth employment welfare and trade as well as their feedback to the electricity sector the development of pv module and wind turbine prices is modeled using learning curves at the global scale i e depending on global capacity installed of each of these technologies national capacity additions in turn depend on global prices national policies and economic development while demand pull policies enhance capacity installations technology push policies do not seem to have a significant direct influence the empirical results confirm the overshooting of pv installations in germany which can be slowed down by introducing degression of feed in tariffs over time

are classical experiments needed for manpower policy the critical element that distinguishes classical experiments from all other modes of analysis is the random assignment of treatment to enrollees in a study this paper examines the major methodological advantages of random assignment for the purpose of estimating the effectiveness of current manpower policy it also reviews the claimed methodological and ethical objections to experiments the main valid objection to an experiment is neither methodological nor ethical it is the experiment s cost in relation to that of nonexperimental methods of analysis the authors argue that the offsetting gain from experimentation is the inherent reliability of experimental estimates of treatment effects the paper offers a simple framework for deciding whether the improved reliability of treatment effect estimates is worth the added cost of experimentation it concludes with an assessment of the actual value of experiments for evaluating current manpower policies

a microeconometric evaluation of the active labour market policy in switzerland in the second part of the 1990 s switzerland conducted an ambitious active labour market policy almp encompassing a wide variety of programmes we evaluate the effects of these programmes on the individual employment probability of potential participants our econometric analysis uses unusually informative data origi nating from administrative unemployment and social security records we apply a matching es timator adapted for the case of multiple programmes we find substantial positive effects for one particular programme that is a unique feature of the swiss almp it consists of a wage subsidy for temporary jobs in the regular labour market that would otherwise not be taken up by the unemployed we also find large negative effects for traditional employment programmes oper ated in sheltered labour markets for training courses the results are mixed doi 10 1111 1468 0297 00072 download internet appendix pdf 2 590 kb

on the external validity of laboratory tax compliance experiments i introduction laboratory methods are now widely accepted as a methodological approach in economics and increasingly they have been used to examine specific public policy issues there is much to be gained from careful laboratory experiments they offer a low cost means of testing and replicating policy innovations and they generate precise data on individual behavior thereby allowing estimation of behavioral responses importantly they allow many policy innovations to be introduced singly and exogenously in a controlled environment and as a result laboratory experiments are typically seen as having a high degree of internal validity brewer 2000 campbell and stanley 1966 shadish cook and campbell 2002 because the causal relation between variables can be properly demonstrated however as emphasized by plott 1987 using laboratory experiments can allow more general inferences regarding human behavior only when the setting implemented in the laboratory parallels what is observed in the naturally occurring world even beyond this requirement of parallelism is the need for generalizing behavioral observations from the laboratory to the field or external validity internal validity can be demonstrated through the evaluation of the design however external validity can only be verified empirically and only with respect to the specific setting being investigated this paper investigates the external validity of laboratory experiments and does so in the context of experiments on tax compliance behavior tax evasion is central to many important policy questions current estimates report the tax gap or difference between taxes owed and taxes paid in the united states to be 450 billion annually internal revenue service 2012 beyond these massive revenue losses evasion creates major misallocations in resource use when individuals alter their behavior to cheat on their taxes its presence requires that government expend resources to detect noncompliance to measure its magnitude and to penalize tax evasion evasion alters the distribution of income in arbitrary unpredictable and unfair ways and it may contribute to feelings of unjust treatment and disrespect for the law more broadly it is not possible to understand the true impact of taxation without recognizing the existence and the effects of tax evasion laboratory methods have been used to examine a wide range of policies that may affect the compliance decision policies that have not always proven amenable to either theoretical analyses or empirical analyses with field data however laboratory studies of compliance are sometimes viewed with skepticism the most common criticism is that the student subjects typically used in experiments may not be representative of taxpayers undergraduates may have little experience with filing tax returns and their economic and demographic backgrounds may differ from those of taxpayers another criticism is that the context of laboratory compliance experiments does not closely enough resemble the context in which actual compliance decisions are made as a result there is a concern that experimental results on policy innovations that rely upon student subjects in laboratory compliance experiments cannot be generalized to the population it is this issue that we examine here building on previous research we present several types of evidence on the external validity of experiments on individual compliance decisions a first question examines whether behavior of laboratory participants is replicated by behavior of individuals making a similar decision in the naturally occurring world that is do participants in laboratory experiments exhibit different patterns of behavior than individuals in a similar naturally occurring setting to answer this question we utilize a special data set from the u s internal revenue service irs assembled as part of its national research program nrp

bounding causal effects using data from a contaminated natural experiment analysing the effects of teenage childbearing in this paper we consider what can be learned about causal effects when one uses a contaminated instrumental variable in particular we consider what inferences can be made about the causal effect of teenage childbearing on a teen mother s subsequent outcomes when we use the natural experiment of miscarriages to form an instrumental variable for teen births miscarriages might not meet all of the conditions required for an instrumental variable to identify such causal effects for all of the observations in our sample however it is an appropriate instrumental variable for some women namely those pregnant women who experience a random miscarriage although information from typical data sources does not allow one to identify these women we show that one can adapt results from horowitz and manski 1995 on identification with data from contaminated samples to construct informative bounds on the causal effect of teenage childbearing we use these bounds to re examine the effects of early chilbearing on the teen mother s subsequent educational and labour market attainment as considered in hotz mcelroy and sanders 1995a 1995b consistent with their study these bounds indicate that women who have births as teens have higher labour market earnings and hours worked compared to what they would have attained if their childbearing had been delayed

dynamics of energy technologies and global change technological choices largely determine the long term characteristics of industrial society including impacts on the natural environment however the treatment of technology in existing models that are used to project economic and environmental futures remains highly stylized based on work over two decades at iiasa we present a useful typology for technology analysis and discuss methods that can be used to analyze the impact of technological changes on the global environment especially global warming our focus is energy technologies the main source of many atmospheric environmental problems we show that much improved treatment of technology is possible with a combination of historical analysis and new modeling techniques in the historical record we identify characteristic l such network e ects yield high barriers to entry even for superior competitors these simple observations allow three improvements to modeling of technological change and its consequences for global environmental change one is that the replacement of long lived infrastructures over time has also replaced the fuels that power the economy to yield progressively more energy per unit of carbon pollution from coal to oil to gas such replacement has d they also include endogenous generation of s we show that doing so can yield projections with lessened environmental impacts without necessarily incurring negative e ect on the economy arriving on that path by the year 2100 depends on intervening actions such as incentives to promote greater diversity in technology and lower barriers to entry for new infrastructures that could accelerate historical trends of decarbonization 1999 elsevier science ltd all rights reserved

estimating the effect of financial aid offers on college enrollment a regression discontinuity approach an important problem faced by colleges and universities that of evaluating the effect of their financial aid offers on student enrollment decisions is complicated by the likely endogeneity of the aid offer variable in a student enrollment equation this article shows how discontinuities in an east coast college s aid assignment rule can be exploited to obtain credible estimates of the aid effect without having to rely on arbitrary exclusion restrictions and functional form assumptions semiparametric estimates based on a regression discontinuity rd approach affirm the importance of financial aid as an effective instrument in competing with other colleges for students

the impact of conditional cash transfers on consumption and investment in nicaragua abstract this article examines the impact of a nicaraguan conditional cash transfer programme on measures of expenditures and productive investment despite clear evidence from a randomised evaluation that the programme increased current expenditures there is little evidence that it increased agricultural or non agricultural investment an estimated marginal propensity to consume out of the transfers of nearly one combined with no effect of cumulative past transfers on current consumption corroborate the direct evidence on investment in contrast to gains made in human capital investment the potential for long term increases in consumption as a result of other forms of increased investment may be limited

are there lessons for africa from china s success against poverty at the outset of china s reform period the country had a far higher poverty rate than for africa as a whole within five years that was no longer true this paper tries to explain how china escaped from a situation in which extreme poverty persisted due to failed and unpopular policies while acknowledging that africa faces constraints that china did not and that context matters two lessons stand out the first is the importance of productivity growth in smallholder agriculture which will require both market based incentives and public support the second is the role played by strong leadership and a capable public administration at all levels of government

on the relevance and composition of gifts within the firm evidence from field experiments we investigate the economic relevance and the composition of gifts within a firm where output is contractible we develop a structural behavioral model that identifies workers optimal reaction to monetary gifts received from their employer we estimate the model using data from two separate field experiments conducted within a tree planting firm we use the estimated structural parameters to generalize beyond the experiment simulating how workers would react to different gifts on the part of the firm within different labor market settings we find that gifts have a role to play within this firm increasing in importance when the workers outside alternatives deteriorate profit maximizing gifts would increase profits within slack labor markets by up to 10 on average and by up to 17 for certain types of workers

implications of higher global food prices for poverty in low income countries in many poor countries the recent increases in prices of staple foods raise the real incomes of those selling food many of whom are relatively poor while hurting net food consumers many of whom are also relatively poor the impacts on poverty will certainly be very diverse but the average impact on poverty depends upon the balance between these two effects and can only be determined by looking at real world data results using household data for ten observations on nine low income countries show that the short run impacts of higher staple food prices on poverty differ considerably by commodity and by country but that poverty increases are much more frequent and larger than poverty reductions the recent large increases in food prices appear likely to raise overall poverty in low income countries substantially

heterogeneous impacts of conditional cash transfers evidence from nicaragua abstract in the last decade the most popular policy tool used to increase human capital in developing countries has been the conditional cash transfer program a large literature has shown significant mean impacts on schooling health and child labor this paper examines heterogeneous effects using random assignment data from the red de proteccion social in rural nicaragua using interactions between the targeting criteria and the treatment indicator estimates suggest that children located in more impoverished localities experienced a larger impact of the program on schooling in 2001 but this finding is reversed in 2002 estimated quantile treatment effects indicate that there is considerable heterogeneity in the impacts of the program on the distribution of food expenditures as well as total expenditures in particular households at the lower end of the expenditure distribution experienced a smaller increase in expenditures this study also presents evidence of the rank invariance assumption to hel

substitution and dropout bias in social experiments a study of an influential social experiment this paper considers the interpretation of evidence from social experiments when persons randomized out of a program being evaluated have good substitutes for it and when persons randomized into a program drop out to pursue better alternatives using data from an experimental evaluation of a classroom training program we document the empirical importance of control group substitution and treatment group dropping out evidence that one program is ineffective relative to close substitutes is not evidence that the type of service provided by all of the programs is ineffective although that is the way experimental evidence is often interpreted

a reassessment of the effect of income maintenance on marital dissolution in the seattle denver experiment cain and wissoker claim that income maintenance treatment had no effect on marital dissolution in the seattle denver income maintenance experiment yet parametric and nonparametric analyses reveal that there was a significant increase in the dissolution rate for blacks and whites but not chicanos this conclusion holds for many different specifications including a number that allow free form time variation in response while cain and wissoker s analyses and results differ in many ways from that of groeneveld hannan and tuma consideration of the full set of estimates including both main effects and interaction effects and analyses of the complete samples reveal that their analyses agree that the income maintenance treatment increased rates of marital dissolution for blacks and whites

using experiments to evaluate performance standards what do welfare to work demonstrations reveal to welfare reformers this paper examines how experimental demonstrations can be used to inform planners about the efficacy of social programs in light of a performance standard the problem is illustrated by considering the situation faced by state governments attempting to design programs to meet the new federal welfare to work standards data from experimental evaluations alone allow only limited inferences about the labor market outcomes of welfare recipients combined with prior information on the selection process however these data are informative suggesting either that the long run federal requirements cannot be met or that these standards will only be met under special circumstances

assets activities and rural income generation evidence from a multicountry analysis summary this paper examines the links between the assets and the economic activities of rural households in developing countries to provide insight into how the promotion of certain key assets particularly education land and infrastructure influences the economic choices of these households nationally representative data from 15 countries which form part of the rural income generating activities riga database are used in the analysis the results indicate that improved land access is linked to agricultural production and thus will lead households to take on average this path for improving household welfare higher levels of education and greater access to infrastructure appear to be most closely linked to non agricultural wage employment