are ghettos good or bad spatial separation of racial and ethnic groups may theoretically have positive or negative effects on the economic performance of those groups we examine the effects of segregation on outcomes for blacks in schooling employment and single parenthood we find that blacks in more segregated areas have significantly worse outcomes than blacks in less segregated areas we control for the endogeneity of location choice using instruments based on political factors topographical features and residence before adulthood a one standard deviation decrease in segregation would eliminate one third of the black white differences in most of our outcomes

technology adoption under seed access constraints and the economic impacts of improved pigeonpea varieties in tanzania dry land legumes well adapted to drought prone areas have largely been neglected in the past despite the good opportunities they offer for income growth and food and nutritional security for the poor this study evaluated the adoption and impact of two farmer and market preferred and disease resistant pigeonpea varieties that were developed and promoted in semi arid tanzania the new varieties were resistant to fusarium wilt a fungal disease devastating the crop however farmers wanting to adopt new varieties did not adopt due to seed access constraints and under developed seed delivery systems adoption of new varieties is therefore analyzed using an augmented double hurdle model that allows estimating variety adoption conditional on seed access thresholds accounting for the additional information on sample separation the study identifies the crucial role of seed access local supply extension education participatory decision making capital and household assets in determining adoption the social economic benefits of the technology and policies for improved seed access were further analyzed using the extended economic surplus method dream model even under restrictive assumptions overall discounted benefits were found to be quite attractive indicating the need for additional efforts to scale up the success story analysis of changes in research benefits from relaxing the seed access constraint showed that net gains would increase by up to 30 if farmer access to improved seeds can be assured smallholder farmers are the major beneficiaries along with consumers and rural net buyers who gain from productivity induced lower market prices

aggregation and pairwise aggregation of demand when the distribution of income is fixed abstract this paper derives necessary and sufficient conditions for pairwise aggregation of the demand functions of a group of consumers conditions under which the mean demand for each pair of consumers satisfies the slutsky restrictions when the distribution of income is fixed the sufficient conditions imply existence of a representative competitive consumer whose demand is the mean demand of the group the necessary conditions imply that such a representative consumer exists for every fixed income distribution only if the consumers have homothetic preferences or alternatively if for each price vector all the consumers income expansion paths lie in the same plane

the potential for agricultural trade among eastern and southern african countries abstract this study investigates the potential for expanding trade in grains and cereals among the countries of eastern and southern africa in the absence of measures of comparative costs and disaggregated bilateral data the method was to determine whether the consumption and production characteristics of the countries imply that trade is below its potential the countries demonstrate characteristics consistent with greater trade in grains and cereals than occurs the region is not a chronic importer of grains except in years of severe drought greater intra regional trade in grains is implied by the significantly different structures of consumption and production across countries these differences suggest that greater grain self sufficiency for each country taken separately might not be efficient but it could be for the region as a whole along with the evidence for differences in consumption and production patterns goes statistical support for the likelihood that the countries could absorb each other s surpluses and fill each other s shortages over time

the sensitivity of returns to research calculations to supply elasticity returns to research are thought to be robust under alternative supply elasticity assumptions we show both conceptually and numerically how advances in approximating social benefits make returns to research sensitive to the supply elasticity despite this greater sensitivity these advances retain conceptual and practical advantages we make recommendations for dealing with the increased sensitivity copyright 2002 oxford university press

approaches to the privatization of fertilizer marketing in africa abstract agricultural marketing privatization has been a central feature of structural adjustment recommendations this paper briefly analyses the main issues related to privatization in the fertilizer sector in africa reviews developments and examines possible reasons for the relatively slow progress to date constraints to effective privatization are identified and policy changes and other reforms necessary if fertilizer marketing privatization is to succeed are proposed effective privatization will not be achieved without detailed planning and consideration of potential problems at an early stage

policies for african seed enterprise development abstract the commercial seed sector has been slow to develop in sub saharan africa the paper examines the major impediments and identifies areas in which seed policies can be strengthened seed enterprise development has been hampered by regulatory frameworks that favor parastatal enterprises and that inhibit commercial innovation in addition government and donor projects provide large amounts of free or subsidized seed that further discourages seed enterprise development in addition to regulatory reform and the curtailment of many seed distribution projects there are other policy changes that need to be implemented national agricultural research institutes need to invest more resources in promoting their varieties and helping to stimulate commercial seed production greater emphasis is required on regional strategies for public plant breeding and private seed marketing national policies need to strengthen input marketing capacity and infrastructure finally donors governments and ngos should shift from trying to encourage village level commercial seed production and instead strengthen farmers capacities to assess new varieties and to be effective consumers of commercial inputs

thinking fast and slow some field experiments to reduce crime and dropout in chicago we present the results of three large scale randomized controlled trials rcts carried out in chicago testing interventions to reduce crime and dropout by changing the decision making of economically disadvantaged youth we study a program called becoming a man bam developed by the nonprofit youth guidance in two rcts implemented in 2009 2010 and 2013 2015 in the two studies participation in the program reduced total arrests during the intervention period by 28 35 reduced violent crime arrests by 45 50 improved school engagement and in the first study where we have follow up data increased graduation rates by 12 19 the third rct tested a program with partially overlapping components carried out in the cook county juvenile temporary detention center jtdc which reduced readmission rates to the facility by 21 these large behavioral responses combined with modest program costs imply benefit cost ratios for these interventions from 5 to 1 up to 30 to 1 or more our data on mechanisms are not ideal but we find no positive evidence that these effects are due to changes in emotional intelligence or social skills self control or grit or a generic mentoring effect we find suggestive support for the hypothesis that the programs work by helping youth slow down and reflect on whether their automatic thoughts and behaviors are well suited to the situation they are in or whether the situation could be construed differently jel codes c91 c93 d03 d1 i24 i3 i32 k42

liberalization and agricultural marketing recent causes and effects in third world economies abstract from merely being the dream of some economists a few years ago the liberalization of national marketing systems has suddenly taken a tangible form on a worldwide scale why have governments hitherto clinging to state participation and controls especially in their agricultural and currency trading systems changed their policies so swiftly are market structures entrepreneurial and private sector financing potentials capable of filling the gaps will the liberalization move lead of the envisaged competitive market and price mechanism with its resource mobilizing effects or will this move lacking efficient implementation get stuck somewhere in between inviting resurrection of interventionist policies this article provides both evidence and analysis on these questions in an introductory assessment of the dynamic process of radical policy changes faced by the food and agricultural marketing systems in most developing countries today

encouraging private sector research for tropical agriculture summary agricultural needs in poor tropical countries differ significantly from those in temperate rich countries yet little agricultural research is performed on products for the tropics private research is particularly concentrated in rich countries this is a result of significant failures in the market for research and development r d in particular the difficulty of preventing the resale of seed in developing countries to encourage private r d in tropical agriculture traditional funding of research may be usefully supplemented by a commitment to reward developers of specific new agricultural technologies rewards tied to adoption may be especially useful in increasing up take an illustration of how a commitment to reward developers of new agricultural technologies might work is provided

formal and informal seed systems in kenya supporting indigenous vegetable seed quality indigenous vegetables play an important role in kenyan food security but production is limited by poor seed quality traditionally seeds have been traded through informal networks but a new form

the causes of africa s food crisis abstract this paper examines the causes of africa s food crisis by examining patterns of food imports the econometric results indicate that the rise in food imports during 1970 87 can be explained by a combination of demographic policy and economic factors which have raised domestic demand for imported food these factors include urban migration peaks in income especially during commodity booms lower international prices of food and distorted exchange rates after accounting for these factors the residual trend in food imports per capita is negative over this period evidence is also presented showing that in ghana policy reforms have led to reverse migration from urban to rural areas

can the public sector meet the challenge of private research commentary on falcon and fowler and pingali and traxler abstract the growth of private sector participation in agricultural research has serious implications for pro poor technology development but there are other factors that must be considered new plant varieties are not the only things standing between resource poor farmers and secure livelihoods and institutional strengthening is also necessary in addition the current state of public agricultural research is cause for concern it is not clear how many effective public private partnerships can be formed the public sector needs a much clearer definition of its targets and priorities and funding strategies for national and international agricultural research must be overhauled

policies to promote cereal intensification in ethiopia the search for appropriate public and private roles over the past decade policymakers have been searching for an appropriate blend of public and private sector roles to accelerate the intensification of food staple production smallholder commercialization and sustainable market development in sub saharan africa in ethiopia steps taken to liberalize markets in the 1990s and promote fertilizer and seed packages have yet to generate payoffs in terms of higher cereal yields lower food prices or reduced dependency on food aid this raises concern about the performance of the agricultural sector specifically in terms of the systems for providing improved seed fertilizer credit and extension services this paper examines the evolving roles of the public and private sectors in intensifying cereal production in ethiopia findings suggest that while ethiopia has an admirable record of supporting agriculture its state led policies has now outlived their usefulness these findings for ethiopia offer lessons that are potentially applicable to other sub saharan african countries facing similar challenges

is the united states still a land of opportunity recent trends in intergenerational mobility abstract we present new evidence on trends in intergenerational mobility in the united states using administrative earnings records we find that percentile rank based measures of intergenerational mobility have remained extremely stable for the 1971 1993 birth cohorts for children born between 1971 and 1986 we measure intergenerational mobility based on the correlation between parent and child income percentile ranks for more recent cohorts we measure mobility as the correlation between a child s probability of attending college and her parents income rank we also calculate transition probabilities such as a child s chances of reaching the top quintile of the income distribution starting from the bottom quintile based on all of these measures we find that children entering the labor market today have the same chances of moving up in the income distribution relative to their parents as children born in the 1970s however because inequality has risen the consequences of the birth lottery t

peanut research and poverty reduction impacts of variety improvement to control peanut viruses in uganda a procedure is developed and applied for predicting ex ante impacts of agricultural research on aggregate poverty using as an example the poverty reducing impact of peanut research in uganda market level information on economic surplus changes is combined with a procedure for allocating income changes to individual households characteristics of farmers that affect their likelihood of technology adoption are used to create a technology adoption profile associated changes in poverty resulting from adoption are computed using poverty indices predicted income changes at the household level are aggregated to the market level and reconciled with calculations of economic surplus changes

are emily and greg more employable than lakisha and jamal a field experiment on labor market discrimination we study race in the labor market by sending fictitious resumes to help wanted ads in boston and chicago newspapers to manipulate perceived race resumes are randomly assigned african american or white sounding names white names receive 50 percent more callbacks for interviews callbacks are also more responsive to resume quality for white names than for african american ones the racial gap is uniform across occupation industry and employer size we also find little evidence that employers are inferring social class from the names differential treatment by race still appears to still be prominent in the u s labor market jel j71 j64

seed regulation choices on the road to reform major changes in national seed systems including the rapid development of commercial seed enterprises the growth of non governmental organization ngo seed projects and the concomitant decline of public sector seed provision call for a re examination of seed regulatory frameworks in developing countries privatization and deregulation are often presented as logical partners but the nature of seed system change and the complexities of regulatory responsibility make seed regulatory reform less straightforward than it first appears challenges include the limited opportunities for commercial seed development the need to provide guidance to seed systems in transition the international pressures for plant variety protection pvp and significant differences among various national regulatory approaches problems with the conduct of current seed regulations include significant inefficiency the use of inappropriate standards inadequate opportunities for the participation of new entrants to the seed system and a lack of transparency specific guidelines are offered for reorganizing variety registration and performance testing providing a balanced opportunity for pvp and broadening participation in seed quality control national seed regulatory agencies will see their role shift from the direct supervision of seed production towards technical and policy support for the development of a wider range of seed provision options

uniqueness and stability of equilibrium in economies with two goods abstract we offer new sufficient conditions ensuring demand is downward sloping local to equilibrium it follows that equilibrium is unique and stable in the sense that rising supply implies falling prices in our setting there are two goods which we interpret as consumption in different time periods and many impatience types agents have the same bernoulli utility function but the types differ arbitrarily in time preference our main result is that if endowments are identical and utility displays nonincreasing absolute risk aversion then market demand is strictly downward sloping local to equilibrium we discuss implications for the literature surrounding diamond and dybvig 1983

farmer s rights and genetic conservation in traditional farming systems abstract crop genetic resources are concentrated in some of the world s poorest farming systems these resources have been used by industrial countries without compensating farmers concerns for equity and conservation have led to proposals to protect crop genetic resources as intellectual property this paper argues that conventional intellectual property regulations e g utility patents and plant variety protection should not be used to protect crop genetic resources it suggests that farmers rights as an alternate form of intellectual property rights be used to indirectly compensate farmers by supporting genetic conservation it examines methods of in situ conservation for crop genetic resources

ngos and seed provision to smallholders in developing countries abstract public sector provision of improved seeds in developing countries has often fallen foul of government failure while commercial seed supply has faced unusually high transactions costs and some market failure both have met difficulties in providing appropriate seed for marginal farm lands into the gap have come nongovernmental organisations ngos most of them involved in small scale seed multiplication and distribution evidence from a review of 19 ngo programs suggests that their seed activities operate on a small scale sometimes with little distinctive technical competence and tend to ape other formal sector methods above all they face a challenge in making their efforts sustainable the most promising avenue seems to lie in their supporting the growth of small seed production and distribution enterprises at farm and village level

divergent paths a new perspective on earnings differences between black and white men since 1940 we present new evidence on the evolution of black white earnings differences among all men including both workers and nonworkers we study two measures i the level earnings gap the racial earnings difference at a given quantile and ii the earnings rank gap the difference between a black man s percentile in the black earnings distribution and the position he would hold in the white earnings distribution after narrowing from 1940 to the mid 1970s the median black white level earnings gap has since grown as large as it was in 1950 at the same time the median black man s relative position in the earnings distribution has remained essentially constant since 1940 so that the improvement then worsening of median relative earnings have come mainly from the stretching and narrowing of the overall earnings distribution black men at higher percentiles have experienced significant advances in relative earnings since 1940 due mainly to strong positional gains among those with college educations large relative schooling gains by blacks at the median and below have been more than counteracted by rising return to skill in the labor market which has increasingly penalized remaining racial differences in schooling at the bottom of the distribution

a theory of intergenerational mobility we study the link between market forces cross sectional inequality and intergenerational mobility emphasizing complementarities in the production of human capital we show that wealthy parents i

peasant household behaviour with missing markets some paradoxes explained a model of peasant household behavior under varying degrees of household specific food and labor market failures is constructed to show that these structural features can explain several well known patterns of peasant response which have often been attributed to peculiar motives presumed specific to peasants the model explains sluggish response to cash crops prices and high instability in perceived food and labor scarcities the key role of manufactured consumer goods prices in stimulating peasants effort in cash crops production the effectiveness of taxation as opposed to incentives in stimulating cash crops production and the key role of technological change in food production to enhance cash crop production results are obtained analytically in the case of one market failure and by numerical simulation with more than one

looking beyond national boundaries regional harmonization of seed policies laws and regulations countries in west eastern and southern africa are pursuing the regional harmonization of their seed laws and regulations common regulatory frameworks are expected to reduce the costs of trading seed and encourage scale economies in seed production as a result commercial seed production is expected to expand providing farmers with improved access to new varieties and stimulating productivity growth the impact of these harmonization efforts will depend on the details of the regulatory agreements policy makers are being asked to consider a complicated series of trade offs between stricter measures for quality control and the need to encourage the multiplication and distribution of lower cost seed they are also being confronted with two possible views of sectoral development one view entails the pursuit of better linkages between distinct national seed markets the second involves the development of truly regionalized seed markets where seed can be readily produced in one country and sold in any other country this implies greater regional interdependence of seed supply the paper compares the harmonization agreements being pursued in each of the three african regions and progress in implementing the accords efforts to adapt international seed market standards to the contingencies of african markets are discussed and priorities for further policy analysis are identified

is market liberalization compatible with food security storage trade and price policies for maize in southern africa abstract concern for the negative impacts of staple food price fluctuations limits the extent to which governments in low income countries are willing to liberalize their agricultural markets these concerns are legitimate as such price fluctuations can lead to high transactions costs for poor consumers in the short run and low growth in the long run however past government attempts to stabilize food prices completely have been expensive and ineffective use of a dynamic programming optimization model suggests that a different type of policy regime could reduce price variability significantly compared to what would prevail in free markets and could accomplish this at relatively low cost this policy regime includes allowing some official price flexibility with respect to changes in production and world price exporting when regional market opportunities exist and holding considerably lower stocks than in the past

approximate aggregation under uncertainty abstract for a collection of agents with von neumann morgenstern preferences a price independent income distribution and identical probability beliefs there exists a von neumann morgenstern approximate aggregator the risk tolerance of the approximate aggregator is equal to the sum of the individual agent risk tolerances at prices which yield constant risk free contingent consumption the application of the approximate aggregator to standard asset pricing models in finance is discussed briefly

the private delivery of public crop varieties rice in andhra pradesh although there has been a considerable growth of private seed enterprises in developing countries there are few examples of the private delivery of seed of public crop varieties that are not hybrids this paper discusses the example of rice in andhra pradesh where private enterprise is supplying an increasing proportion of the seed used by farmers the institutional conditions for private expansion into rice seed are examined the paper discusses instances where low transaction costs allow for the emergence of a wide range of seed enterprises but despite the success of private seed delivery inadequate attention has been given to incentives for variety promotion and to the importance of consumer education

an empirical analysis of fertilizer use in pakistan one of the stylized facts in developing countries is the wide variation in agricultural per acre input and output levels across farm households here we focus on the variation in the level of chemical fertilizer applied in particular to high yielding wheat the model used to explain the variation in fertilizer input across farms incorporates the process by which zeros are generated in particular differentiating between households who do not apply because of lack of access and those who do not apply out of choice we find that access is positively correlated with farm size but that among users per acre fertilizer levels decrease with farm size we interpret the latter by appealing to input choice under uncertainty with this interpretation our results suggest that although larger farms have a higher level of non stochastic wealth which in the presence of decreasing absolute risk aversion has the effect of increasing fertilizer intensity with farm size the presence of increasing relative risk aversion means that the net relationship between farm size and fertilizer intensity is negative this latter affect appears to dominate any tendancy for higher fertilizer intensity on larger farms arising from better knowledge or irrigation facilities

off farm labour allocation decisions in small scale rural households in zimbabwe the double hurdle model is used to analyse the off farm labour decisions of small scale agricultural household members in the shamva district of zimbabwe the approach permits the joint modelling of the decision to participate in the labour market and the decision regarding the amount of time allocated to work results indicate that a number of variables notably gender education and assets indeed have effects which are qualitatively and quantitatively different in terms of participation and hours worked overall the empirical analysis confirms the importance of individual characteristics such as gender and education and household farm characteristics e g land area accessible to the household productive assets remittances and the agricultural terms of trade in influencing the labour market decisions of rural household members

adoption of modern varieties farmers welfare and crop biodiversity evidence from uganda abstract this paper assesses the impact of modern varieties adoption on farmers welfare and crop biodiversity conserved in situ using nationally representative data collected in 2009 2010 in uganda an endogenous switching regression model estimates the net economic and environmental effects of switching from local landraces to modern species results show that after controlling for market and agro ecological factors the local varieties perform better than modern ones in marginalized and climatic vulnerable areas crop biodiversity shows to play a fundamental role in farmers risk minimizing strategies when the available modern varieties are not adaptable to the local context and not supported by the required level of agro intensification rural development policies should consider the heterogeneity in the adoption returns and support diversity conservation as a national strategic asset for a suitable bioprospecting and a best fitting agricultural system implementation

impact of tissue culture banana technology on farm household income and food security in kenya while tissue culture tc technology for vegetative plant propagation is gradually gaining in importance in africa rigorous assessment of broader welfare effects for adopting smallholder farm households is lacking using survey data and accounting for selection bias in technology adoption we analyze the impact of tc banana technology on household income and food security in kenya to assess food security outcomes we employ the household food insecurity access scale hfias a tool that has not been used for impact assessment before estimates of treatment effects models show that tc banana adoption combined with improved crop management causes considerable increases in farm and household income technology adoption also reduces relative food insecurity in a significant way these results indicate that tc technology can be welfare enhancing for adopting farm households adoption should be further promoted through upscaling appropriate technology delivery systems

the effects of exposure to better neighborhoods on children new evidence from the moving to opportunity experiment the moving to opportunity mto experiment offered randomly selected families housing vouchers to move from high poverty housing projects to lower poverty neighborhoods we analyze mto s impacts on children s long term outcomes using tax data we find that moving to a lower poverty neighborhood when young before age 13 increases college attendance and earnings and reduces single parenthood rates moving as an adolescent has slightly negative impacts perhaps because of disruption effects the decline in the gains from moving with the age when children move suggests that the duration of exposure to better environments during childhood is an important determinant of children s long term outcomes jel i31 i38 j13 r23 r38

invisible hands indigenous knowledge and inevitable fads challenges to public sector agricultural research in ghana abstract support for public sector agricultural research in developing countries is declining at the same time many donors feel that alternative institutions will be able to perform the functions traditionally reserved for the public sector these alternatives include private sector initiatives nongovernment organizations and farmer organizations and highly publicized special projects in agricultural development the logic of these alternatives is examined using evidence on maize research in ghana although each of the alternatives offers contributions and public sector research undoubtedly requires an overhaul emphasis is placed on the necessity of continued suport to building strong public sector agricultural research capacity

ethnic capital and intergenerational mobility this paper analyzes the extent to which ethnic skill differentials are transmitted across generations i assume that ethnicity acts as an externality in the human capital accumulation process the skills of the next generation depend on parental inputs and on the quality of the ethnic environment in which parents make their investments or ethnic capital the empirical evidence reveals that the skills of today s generation depend not only on the skills of their parents but also on the average skills of the ethnic group in the parent s generation

privatization and the roles of public and private institutions in agricultural research in sub saharan africa abstract privatization has become a popular panacea for solving the organizational problems of ldc governments this paper considers the role of the private sector in agricultural research especially in sub saharan africa the first section provides a brief background by stating the main arguments for market failure in the allocation of resources to research followed by the reasoning behind the reaction against public intervention the arguments for intervention are then applied to the different areas of agricultural research activity to show that the level of public intervention should depend on the type of research we suggest that there are several criteria for defining public and private activities and that there are few research activities that can be easily classified as purely public or purely private this implies that the appropriate split between public and private research has several dimensions and that efficient institutional arrangements will be specific to particular activities the evidence suggests that there are sound economic arguments for changing the domains of the public and private sectors which should not be static both economic development and technical innovations such as biotechnology will move the boundary in favour of increased private activity but the public and private contributions should be viewed as complementary investments rather than substitutes

the seed and agricultural biotechnology industries in india an analysis of industry structure competition and policy options since the late 1980s technological advances and policy reforms have created new opportunities for private sector investment in india s seed and agricultural biotechnology industries these changes have had a significant impact on cotton yields and output in india but less so for rice and wheat the country s main cereal staples for which yield growth rates are tending toward stagnation this analysis examines the structures of these industries their potential effects on competition and innovation and the policies that may improve both industry performance and the delivery of new productivity enhancing technologies to india s cereal production systems our findings suggest that more substantive policy reforms are needed to encourage further innovation reduce regulatory uncertainty and encourage firm and industry level growth while continued public spending on agricultural research is needed to support technological change

adoption of improved chickpea varieties kribhco experience in tribal region of gujarat india abstract the study aims to track adoption of improved chickpea varieties and assess their on farm benefits in some remote and backward tribal villages in gujarat india where few newly developed varieties were introduced by a non government organization it also determines key factors which were influencing their adoption the study found that adoption of improved chickpea varieties was gradually increasing by replacing a prominent local variety duration of crop maturity farm size yield risk and farmers experience of growing chickpea crop were significantly influencing their adoption the on farm benefits as a result of improved varieties were realized in terms of increased yield levels higher income and labor productivity more marketable surplus price premium and stabilized yields in fluctuating weather breeding short duration varieties with stable yield levels under varying weather and organizing seed multiplication and dissemination in regions where moisture stress is a problem during maturity of chickpea are the major suggestions

sadcc food security strategies evolution and role abstract over the last seven years the scope of strategies promoted by the sadcc food security program has broadened steadily at first there was an almost complete preoccupation with food production the program now includes projects related to cereal market stabilization regional trade and food aid most recently consumption objectives have been made an explicit concern of the program this paper traces the evolution of policy underlying this expansion of interest cooperation between sadcc member states rests on the principle that more can be achieved by joint effort than by individual states acting alone however experience to date suggests that it is easier to define the benefits of regional collaboration than to capture them the sadcc food security program requires technical and financial capacity in order to pursue its objectives but the success of collaborative ventures rests to a more critical extent on the level of confidence which exists among member states

determinants of farmers indigenous soil and water conservation investments in semi arid india abstract this paper investigates the determinants of farmers indigenous soil and water conservation investments in the semi arid tropics of india a simple theoretical model is used to develop hypotheses about the determinants of investment under alternative factor market conditions and these are tested using data on conservation investment from three villages we find that conservation investment is significantly lower on leased land in two of the study villages and lower on plots that are subject to sales restrictions in one village suggesting the potential for land market reforms to increase conservation investment in one village households with more adult males more farm servants and less land invest more in conservation as predicted by the model of imperfect labor markets and households with more debt and off farm income invest more consistent with the model of imperfect credit markets evidence that conservation investment is affected by factor market imperfections is weaker in the other villages where investments are much larger suggesting transaction costs as the source of the differences between villages other factors that have a significant effect on investment include the farmer s education and caste characteristics of the plot size slope irrigation status and quality ranking and the presence of existing land investments the results suggest the importance of accounting for differences across communities and households in factor market and agroclimatic conditions in designing programs to promote investments in soil and water conservation

input use and market development in sub saharan africa an overview abstract this paper sets forth the background and objectives of this special issue trends in input use since 1980 are reviewed and a conceptual framework is presented for analyzing problems of input use and formulating strategies for resolving them reasons for low levels of fertilizer use by smallholder farmers are summarized briefly the essential points of the papers in the special issue and their implications for further expansion of input use in sub saharan africa are then outlined

policy reform and reform myopia abstract recent decades witnessed major efforts on the part of many developingcountry government to alter existing economic policies and undo constraints on agricultural growth this article compares the dynamics of agricultural policy reform initiatives of the 1970s with those of the 1980s the authors argue that when the definition of what is needed in terms of policy to get agriculture moving changes the political economy of policy making and implementation also shifts such shifts are often accompanied by a myopic focus on new crisis definitions and new policy solutions to the detriment of more integrated approaches to agricultural development

understanding black white wage differentials 1960 1990 understanding black white wage differentials 1960 1990 author s james j heckman thomas m lyons petra e todd source the american economic review vol 90 no 2 papers and proceedings of the one hundred twelfth annual meeting of the american economic association may 2000 pp 344 349 published by american economic association stable url http www jstor org stable 117248 accessed 16 08 2008 00 56

policies for promoting regional agricultural trade abstract this paper deals with the political issues of trade liberalization after giving a brief account of the potential and barriers to intraregional trade in southern africa the position in malawi zambia and zimbabwe supports the view that there is a significant potential for trade barriers to trade are due to the external trading regime internal policies and external factors notably food aid the liberalization of the internal food economy is expected to give rise to additional trade flows among the countries regional integration schemes may further contribute to trade expansion however only if they are used as a step to worldwide integration and if an effective institutional framework is secured

challenges of the maize seed industry in eastern and southern africa a compelling case for private public intervention to promote growth abstract following the liberalization and restructuring of the seed sector the maize seed industry in eastern and southern africa has witnessed a proliferation of private seed companies whereas the total number of registered maize seed companies in major maize producing countries increased four fold between 1997 and 2007 the quantity of seed marketed barely doubled suggesting that the seed production and deployment environment is less than perfect a study involving over 92 of all seed providers in east and southern africa in 2007 showed that a number bottlenecks affect the entire maize seed value chain the lack of access to credit constitutes a significant barrier to entry until governments and development partners make credit available to seed entrepreneurs directly or through risk sharing arrangements with commercial banks national seed companies will not grow leaving the seed sector monopolized by the regional and multinational seed companies in addition the transfer of genetic materials between public and private sectors should be improved to allow easy access by seed companies to suitable and adapted varieties to allow for rapid regional spillovers of varieties released in one country to similar agro ecologies in different countries the implementation of the harmonized regional seed laws and regulations should be expedited finally the best strategies that increase the adoption of improved maize varieties should be explored and implemented to enhance seed demand