learning about a new technology pineapple in ghana this paper investigates the role of social learning in the diffusion of a new agri cultural technology in ghana we use unique data on farmers communication patterns to define each individual s information neighborhood conditional on many potentially confounding variables we find evidence that farmers adjust their inputs to align with those of their information neighbors who were surpris ingly successful in previous periods the relationship of these input adjustments to experience further indicates the presence of social learning in addition applying the same method to input choices for another crop of known technol ogy correctly indicates an absence of social learning effects jel d83 013 033 q16

price indexes inequality and the measurement of world poverty i discuss the measurement of world poverty and inequality with particular attention to the role of purchasing power parity ppp price indexes from the international comparison project global inequality increased with the latest revision of the icp and this reduced the global poverty line relative to the us dollar the recent large increase of nearly half a billion poor people came from an inappropriate updating of the global poverty line not from the icp revisions even so ppp comparisons between widely different countries rest on weak theoretical and empirical foundations i argue for wider use of self reports from international monitoring surveys and for a global poverty line that is truly denominated in us dollars

impact of modern agricultural technologies on smallholder welfare evidence from tanzania and ethiopia this paper evaluates the potential impact of adoption of improved legume technologies on rural household welfare measured by consumption expenditure in rural ethiopia and tanzania the study utilizes cross sectional farm household level data collected in 2008 from a randomly selected sample of 1313 households 700 in ethiopia and 613 in tanzania the causal impact of technology adoption is estimated by utilizing endogenous switching regression this helps us estimate the true welfare effect of technology adoption by controlling for the role of selection problem on production and adoption decisions our analysis reveals that adoption of improved agricultural technologies has a significant positive impact consumption expenditure in per adult equivalent terms in rural ethiopia and tanzania this confirms the potential role of technology adoption in improving rural household welfare as higher consumption expenditure from improved technologies translate into lower poverty higher food security and greater ability to withstand risk an analysis of the determinants of adoption highlighted inadequate local supply of seed access to information and perception about the new cultivars as key constraints for technology adoption

technology adoption impact and extension in developing countries agriculture a review of the recent literature given the stagnant agricultural productivity and persistent food insecurity in low income countries notably in sub saharan africa ssa there has been continued interest in the adoption of new technology and its impact on productivity in these regions interestingly there are signs of green revolution in maize and rice in ssa reflected in sharply increasing yield trends in advanced regions to increase crop yields and sustain yield gains recent case studies of technology adoption unanimously recommend the adoption of integrated farm management systems particularly in ssa on the other hand since the 2010s there have been increasing numbers of studies on social network or farmer to farmer technology extension these studies explore more efficient extension systems than traditional public sector extension approaches this article reviews both recent case studies of technology adoption and its productivity impacts as well as studies on agricultural extension to identify common findings shortcomings and major remaining issues

agent compensation and the limits of bonding agents in positions of trust may engage in malfeasance which is difficult to detect this paper develops a model in which employers seek to control malfeasance by paying wages contingent on imperfect monitoring and agents may be required to pay entry fees or post bonds we conclude that entry fees which exceed agents assets are ineffective in controlling malfeasance as a result conditions exist in which it is optimal to pay agents more than their opportunity cost such conditions lead to an excess supply of applicants and allow employers to engage in discrimination at zero cost to themselves

a model of efficiency wages as a signal of firm value we consider performance contracts with firm private information the verifiable components of the contract an up front wage and employment may serve both as a signal and a performance incentive job rent may be necessary for signaling and since efficient signaling is multidimensional there is an inextricable link between job rent and underemployment signaling can explain the lack of explicit bonding in actuality though our basic model is static our underemployment result is not a consequence of firm myopia when the firm is farsighted it will not maximize the joint future surplus if it cannot extract the worker s share at present copyright 1993 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

commodity taxation in welfare states i introduction while the nature of unemployment is diverse a substantial part of unemployment in many developed countries it is argued stems from generous social welfare systems meyer 1990 nickell and layard 1999 and see figure 1 1 in fact the organization for economic cooperation and development oecd data show that countries with generous unemployment insurance ui face high unemployment rates and tend to have high commodity tax rates see figure 2 this paper attempts to account for these empirical patterns in the optimal taxation framework in a general equilibrium context the unemployment mentioned above can be viewed as a result of a a low work incentive induced by generous social insurance welfare benefits combined with b the subsequent employment adjustment by firms e g not renewing employment contracts or hiring a portion of temporary part time workers as regular workers to raise labor productivity to deal with this type of unemployment the government may need to seek reforms of social insurance welfare systems including a reduction in unemployment benefits but the public s redistributive motives often do not permit implementation of such reforms 2 under this socioeconomic constraint this paper raises a question can commodity taxation help reduce unemployment and improve efficiency perhaps a slightly different but equally interesting question that concerns many welfare states in recent decades may be suppose that a society agreed on the expansion of welfare programs in financing the increased welfare expenditure which tax increase consumption taxes or income taxes is more relevant figure 1 omitted figure 2 omitted to address these questions we examine the role of commodity taxation in a general equilibrium model where a taking into account wage unemployment benefits and taxes workers choose work effort that the firm can observe only through costly monitoring and b firms use both wage and monitoring as effort eliciting devices and they fire those caught shirking therefore the chosen level of a worker s effort affects the probabilities of employment and unemployment and thus involuntary unemployment arises from moral hazard 3 in this contractual setting with imperfect information we consider the government s problem of maximizing the representative worker s expected utility using income and commodity taxes we derive new results on commodity taxation and present supportive results using quantitative analysis our key results suggest that commodity taxation can be used to alleviate moral hazard and hence unemployment which can account for why countries with generous social welfare systems tend to adopt high commodity tax rates see figure 2 this main result is based on the following feature of the model given the aforementioned environment optimal commodity and income tax rates can be determined in contrast to the indeterminacy result of atkinson and stiglitz 1976 henceforth as 4 therefore our results provide an explanation for the widely observed coexistence of direct and indirect taxation to illustrate the intuition behind our results consider a situation where a a society provides liberal unemployment benefits for unemployed workers and b the government sets the levels of income and commodity tax rates so as to finance the expenditures for ui and public goods liberal unemployment benefits are equivalent to treating the consumption of unemployed workers favorably i e between states consumption choice distortion which creates moral hazard in the supply of effort under imperfect information about effort obviously drastic reforms in social insurance systems e g cutting benefits can correct moral hazard but the public s redistributive motives do not permit such reforms in this setting we show that strengthening commodity taxation while lessening income taxation penalizes moral hazard which lowers the between states consumption choice distortion leading to a greater supply of effort

impact of improved maize adoption on welfare of farm households in malawi a panel data analysis summary this paper assesses rural households decision to use improved maize varieties in malawi and examines its impact on household welfare using a three year household panel data the distributional effect of maize technology adoption is investigated by looking at impacts across wealth and gender groups we applied control function approach and iv regression to control for possible endogeneity of input subsidy and area under improved maize we found that area under improved maize varieties is positively correlated with own maize consumption income and asset holdings we found evidence that improved maize adoption has a stronger impact on welfare of poorer households

money matters the role of yields and profits in agricultural technology adoption despite the growing attention to technology adoption in the economics literature knowledge gaps remain regarding why some valuable technologies are rapidly adopted while others are not this paper contributes to our understanding of agricultural technology adoption by showing that a focus on yield gains may in some contexts be misguided we study a technology in ethiopia that has no impact on yields but that has nonetheless been widely adopted using three waves of panel data we estimate a correlated random coefficient model and calculate the returns to improved chickpea in terms of yields costs and profits we find that farmers comparative advantage does not play a significant role in their adoption decisions and hypothesize that this is due to the overall high economic returns to adoption despite the limited yield impacts of the technology our results suggest economic measures of returns may be more relevant than increases in yields in explaining technology adoption decisions

a dynamic programming procedure for pricing american style asian options pricing european style asian options based on the arithmetic average under the black and scholes model involves estimating an integral a mathematical expectation for which no easily computable analytical solution is available pricing their american style counterparts which provide early exercise opportunities poses the additional difficulty of solving a dynamic optimization problem to determine the optimal exercise strategy a procedure for pricing american style asian options of the bermudan flavor based on dynamic programming combined with finite element piecewise polynomial approximation of the value function is developed here a convergence proof is provided numerical experiments illustrate the consistency and efficiency of the procedure theoretical properties of the value function and of the optimal exercise strategy are also established

demand disturbances and aggregate fluctuations the implications of near rationality the paper investigates some properties of near rational models of the cycle examining two types of framework in the first an otherwise classical competitive economy is shown to respond to demand disturbances when some firms follow a near rational hiring policy in the second model a dynamic setting is addressed and a criterion termed stochastic near rationality is employed simulation results are consistent with recent empirical findings and suggest that further quantitative evaluation is merited copyright 1987 by royal economic society

simple solutions to the initial conditions problem in dynamic nonlinear panel data models with unobserved heterogeneity i study a simple widely applicable approach to handling the initial conditions problem in dynamic nonlinear unobserved effects models rather than attempting to obtain the joint distribution of all outcomes of the endogenous variables i propose finding the distribution conditional on the initial value and the observed history of strictly exogenous explanatory variables the approach is flexible and results in simple estimation strategies for at least three leading dynamic nonlinear models probit tobit and poisson regression i treat the general problem of estimating average partial effects and show that simple estimators exist for important special cases copyright 2005 john wiley sons ltd

adoption of agricultural innovations in developing countries a survey this paper reviews various studies which have provided a description and possible explanation to patterns of innovation adoption in the agricultural sector the survey points out that the tendency of many studies to consider innovation adoption in dichotomous terms adoption nonadoption may not be appropriate in many cases where the actual decisions are defined over a more continuous range more attention needs to be given to the socio cultural and institutional environment in area studies so that their interrelation with economic factors affecting adoption can be inferred the presence of several interrelated innovations is another aspect that needs to be considered more carefully in future research since a number of simultaneous decisions may be involved furthermore the possibility of regular sequential patterns in adopting components of a new technological package should be specifically addressed in future studies finally the impact of differential adoption rates on land holding distribution merits attention in future research

the effect of taxes on labour in efficiency wage models abstract this paper analyses the effects of labour taxation on wage and employment in a moral hazard efficiency wage model where effort is a continuous variable and workers are risk averse in the model examined ad valorem and specific taxes on labour do not have the same consequences on the real wage both taxes have a negative effect on employment but the imposition of a specific tax causes an increase in the net real wage including firms to raise the quality of their workers these results are compared with those obtained in other versions of the shirking efficiency wage model

hybrid seed and the economic well being of smallholder maize farmers in zambia abstractthe development and diffusion of hybrid maize in zambia since the 1970s is a major achievement in african agriculture but other than profitability studies analyses of how this process has affected the economic well being of smallholder farmers have been few we test the relationship of hybrid seed use with six indicators of economic well being after using the control function instrumental variables approach to test for the endogeneity of hybrid seed use we estimate correlated random effects cre fractional response cre tobit and fixed effects models with a panel of nationally representative data collected in 2002 3 and 2006 7 findings suggest that use of maize hybrids is associated with higher values of household income assets farm and processing equipment and livestock and less deprivation compared to other farmers in nearby villages

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

unemployment long term employment relations and productivity growth using an effort regulation type of efficiency wage model it is demonstrated that a firm may respond to slackening labor markets by acting to increase the intensity with which workers work the magnitude of this work intensity effect depends on the structure of employment relations where long term employment relations are prevalent the effect of labor market slack on work intensity may be diminished these propositions are tested empirically by estimating the effects unemployment and long term employment have on productivity growth in two digit manufacturing industries copyright 1987 by mit press

wage flexibility in the chinese labour market 1989 2009 abstractwage flexibility in the chinese labour market 1989 2009 regional studies china s bureaucratic wage determination system is gradually being replaced by a market based system leading to a novel version of a dual labour market this paper studies wage flexibility in this dual market its principal findings are as follows wages in both sectors have become less responsive to changes in official registered unemployment with an alternative market based measure of unemployment becoming more relevant there is evidence of convergence of flexibility between the two sectors the wages of women exhibit greater flexibility than those of men and there is evidence of differences in wage flexibility between workers who have urban residential rights and rural migrants

foreign direct investment with unemployment and endogenous taxes and tariffs it is well known that high tariffs can induce foreign direct investment or tariff jumping this paper analyzes tariff jumping in the context of a host government which can set specific tariffs and taxes subject to the credibility constraint that the chosen levels be optimal once capital is irreversibly in place the foreign multinational is assumed to choose its location and level of investment strategically taking into account the induced tax and tariff levels in the presence of unemployment the optimal tariff exceeds the optimal tax for any given level of capital investment leading to foreign direct investment

work norms and involuntary unemployment consider the organizational environment of labor management wherein the firm can measure the average performance i e group work norm of its employees but has difficulty in observing the individual worker s performance within the group accordingly the worker s remuneration is based on the observed group norm because of the way in which workers interact among themselves in setting work norms there results an undersupply of effort from a given workforce size furthermore the group work norm is shown to be negatively correlated with the size of the workforce consequently short run unemployment can arise with involuntary features the paper also explores the effectiveness of alternative remuneration schemes in mitigating the inefficiency associated with the group work norm setting

job matching and job competition are lower educated workers at the back of job queues abstract during the cyclical downturn of the 1980s unemployment in the netherlands increased substantially with unemployment rates of lower educated workers increasing more than those of higher educated workers a possible explanation of this phenomenon is job competition between workers with different levels of education another explanation of the diverging unemployment rates is that employers dismiss replaceable lower educated workers before irreplaceable higher educated workers in this paper we scrutinize the job competition explanation our results show that there only is job competition between unemployed workers with an academic and a higher vocational education there is no job competition at lower levels of education

growth and chronic poverty evidence from rural communities in ethiopia abstract what keeps some people persistently poor even in the context of relative high growth in this article we explore this question using a 15 year longitudinal data set from ethiopia we compare the findings of an empirical growth model with those derived from a model of the determinants of chronic poverty we ask whether the chronically poor are simply not benefiting in the same way from the same factors that allowed others to escape poverty or whether there are latent factors that leave them behind we find that this chronic poverty is associated with several initial characteristics lack of physical assets education and remoteness in terms of distance to towns or poor roads the chronically poor appear to benefit from some of the drivers of growth such as better roads or extension services in much the same way that the non chronically poor benefit however they appear to have lower growth in this period related to time invariant characteristics and this suggests that they face a conside

continuous time methods in finance a review and an assessment i survey and assess the development of continuous time methods in finance during the last 30 years the subperiod 1969 to 1980 saw a dizzying pace of development with seminal ideas in derivatives securities pricing term structure theory asset pricing and optimal consumption and portfolio choices during the period 1981 to 1999 the theory has been extended and modified to better explain empirical regularities in various subfields of finance this latter subperiod has seen significant progress in econometric theory computational and estimation methods to test and implement continuous time models capital market frictions and bargaining issues are being increasingly incorporated in continuous time theory the roots of modern continuous time methods in finance can be traced back to the seminal contributions of merton 1969 1971 1973b in the late 1960s and early 1970s merton 1969 pioneered the use of continuous time modeling in financial economics by formulating the intertemporal consumption and portfolio choice problem of an investor in a stochastic dynamic programming setting merton 1973b also showed how such a framework can be used to develop equilibrium asset pricing implications thereby significantly extending the asset pricing theory to richer dynamic settings and expanding the scope of applications of continuous time methods to study problems in financial economics 1 within a span of about 30 years from the publication of merton s inf luential papers continuous time methods have become an integral part of financial economics indeed in certain core areas in finance such as e g asset pricing derivatives valuation term structure theory and portfolio selection continuoustime methods have proved to be the most attractive way to conduct research and gain economic intuition the continuous time approach in these areas has produced models with a rich variety of testable implications the econometric theory for testing continuous time models has made rapid strides in the last decade and has thus kept pace with the impressive progress on the theoretical front one hopes that the actual empirical investigations and estimation using the new procedures will follow suit soon

crop diversity household welfare and consumption smoothing under risk evidence from rural uganda abstract in the wake of climate change there is now a resurgence of interest in the promotion of crop diversification as a climate smart agricultural practice in sub saharan africa the development economics literature suggests that increasing crop diversity is an effective risk management and consumption smoothing strategy in a context characterized by repeated exposure to shocks but weak institutional innovations using panel survey data from rural uganda merged with historical weather data this paper sheds light on the household welfare and consumption smoothing effects of crop diversity we employ instrumental variables methods to control for unobserved heterogeneity and potential reverse causality our study finds that crop diversification is a welfare enhancing strategy that increases consumption and aggregate household diets instrumental variables quantile regression results show that crop diversification generates higher consumption benefits for poorest households in the lower quantile of the consumption distribution than for relatively richer households crop diversification also improves consumption smoothing through reducing households reliance on less effective strategies such as informal insurance and involuntary diet changes as risk coping mechanisms overall the findings suggest that transforming agriculture towards a more diversified cropping system is a viable pathway for improving diets welfare risk management and the resilience of rural households

currency lookback options and observation frequency a binomial approach abstract in the last decade interest in exotic options has been growing especially in the over the counter currency market in this paper we consider lookback currency options which are path dependent we show that a one state variable binomial model for currency lookback options can be constructed with the same computational complexity or should we say simplicity as the standard binomial model furthermore the model allows us to investigate a second very important feature of real life lookback option contracts the observation frequency

policies for agricultural productivity growth and poverty reduction in rural ethiopia summary increasing the productivity of smallholder agriculture holds the key to poverty reduction the empirical literature is limited to ascertain the linkages and the implications for policy uptake in ethiopia we examine the impact of growth in agricultural productivity on household poverty dynamics in rural ethiopia using a panel dataset 1994 2009 findings suggest that government policies aimed at reducing poverty should adopt a growth plus approach designing policy interventions to support agricultural productivity growth plus to protect assets and enhance market access for rural households in the country

smallholders institutional services and commercial transformation in ethiopia this article examines the role of institutional services of credit input supply and extension in the overall commercial transformation process of smallholder agriculture in ethiopia survey data collected in 2006 from 309 sample households in three districts of ethiopia are used for the analyses tobit regression models are used to measure the effect of access to services on the intensity of inputs use for fertilizer and agrochemicals a probit model is used to measure these effects on the adoption of improved seeds intensity of use of seeds is analyzed using an ordinary least squares model logarithmic cobb douglass functions are estimated to analyze the effect of access to services on crop productivity heckman s two stage estimation is used to examine determinants of household market participation and the extents of participation results show that access to institutional support services plays a significant role in enhancing smallholder productivity and market orientation our results imply that expanding and strengthening the institutional services is critical for the intensification and market orientation of smallholder agriculture in ethiopia in particular appropriate incentives and regulatory systems are urgently needed to encourage the involvement of the private sector in the provision of agricultural services

leveling with friends social networks and indian farmers demand for a technology with heterogeneous benefits abstract agricultural technologies typically spread as farmers learn about profitability through social networks this process can be nuanced however when net returns for some farmers may not be positive we investigate how social learning influences demand for a resource conserving technology in eastern uttar pradesh india we identify potential adopters through an experimental auction and randomly select a subset to adopt we exploit this variation in adoption across networks to estimate network effects on demand for the technology one year later using a second auction technology benefits vary and network effects are completely conditional on benefits having a benefiting adopter in one s network increased demand by over 50 whereas having a non benefiting adopter had no effect these effects are strong enough to bring average demand in line with expected benefits for many farmers however demand remains below the market price suggesting that network effects will lead to increased but not rapid widespread adoption

how does population density influence agricultural intensification and productivity this study uses household level panel data on smallholder farmers in ethiopia to estimate how rural population density rpd affects agricultural intensification and productivity our results suggest that higher rpd is associated with smaller farm sizes and has a positive effect on input demand represented by increased fertilizer use per hectare overall increased input use does not lead to a corresponding increase in staple crop yields and thus farm income declines as population density increases this suggests a situation where farmers in areas of high rpd may be stuck in place unable to sustainably intensify in the face of rising rpd and declining farm sizes 2014 elsevier ltd

extending quadrature methods to value multi asset and complex path dependent options abstract the exposition of the quadrature quad method andricopoulos widdicks duck and newton 2003 universal option valuation using quadrature methods journal of financial economics 67 447 471 see also corrigendum journal of financial economics 73 603 2004 is significantly extended to cover notably more complex and difficult problems in option valuations involving one or more underlyings trials comparing several techniques in the literature adapted from standard lattice grid and monte carlo methods to tackle particular types of problem show that quad offers far greater flexibility superior convergence and hence increased accuracy and considerably reduced computational times the speed advantage of quad means that even under the curse of dimensionality it is not necessary to resort to monte carlo methods certainly for options involving up to five underlying assets given the universality and flexibility of the method it should be the method of choice for pricing options involving multiple underlying assets in the presence of many features such as early exercise or path dependency

the economics of vocation or why is a badly paid nurse a good nurse abstract given the longstanding shortage of nurses in many jurisdictions why could not nursing wages be raised to attract more people into the profession we tell a story in which the status of nursing as a vocation implies that increasing wages reduces the average quality of applicants attracted the underlying mechanism accords with the notion that increasing wages might attract the wrong sort of people into the profession and highlights an in efficiency wage mechanism particular to vocations which makes wages sticky up wards the analysis has implications for job design in vocation based sectors such as nursing and teaching

pricing and hedging path dependent options under the cev process much of the work on path dependent options assumes that the underlying asset price follows geometric brownian motion with constant volatility this paper uses a more general assumption for the asset price process that provides a better fit to the empirical observations we use the so called constant elasticity of variance cev diffusion model where the volatility is a function of the underlying asset price we derive analytical formulae for the prices of important types of path dependent options under this assumption we demonstrate that the prices of options which depend on extrema such as barrier and lookback options can be much more sensitive to the specification of the underlying price process than standard call and put options and show that a financial institution that uses the standard geometric brownian motion assumption is exposed to significant pricing and hedging errors when dealing in path dependent options

agricultural technology crop income and poverty alleviation in uganda summary this paper evaluates the ex post impact of adopting improved groundnut varieties on crop income and poverty in rural uganda the study utilizes cross sectional data of 927 households collected in 2006 from seven districts in uganda using propensity score matching methods we find that adopting improved groundnut varieties technology significantly increases crop income and reduces poverty the positive and significant impact on crop income is consistent with the perceived role of new agricultural technologies in reducing rural poverty through increased farm household income this study supports broader investment in agriculture research to address vital development challenges reaching the poor with better technologies however requires policy support for improving extension efforts access to seeds and market outlets that simulate adoption

impacts of subsidized hybrid seed on indicators of economic well being among smallholder maize growers in zambia we test the hypotheses that subsidies on hybrid seed change maize production total household income the severity of poverty and relative deprivation among smallholder maize growers in zambia the analysis contributes to the literature by measuring the quantitative effects of seed as compared to fertilizer subsidies on indicators of household well being rather than input demand we apply a combination of econometric approaches to a nationally representative balanced panel of smallholder maize growing households and invoke the chain rule to generate quantitative estimates of impacts per kilogram of subsidized seed our findings demonstrate that in the initial years of the program subsidized seed enhanced the well being of smallholder maize growers according to each indicator but by small magnitudes simple calculations suggest high private and social benefit cost ratios when benefits are measured in terms of household income although magnitudes are sensitive to seed price and administrative costs

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

optimum taxation in an efficiency wage model recently efficiency wage models of unemployment have received much attention in public economics for example johnson and layard 3 and pisauro 4 have used different versions of these models to examine how an ad valorem tax on labor i e a wage tax or a specific tax an employment tax affects the after tax wage and unemployment the rudimentary model proposed for expositive purpose by yellen 6 can also be used to examine the effects of different labor taxes agell and lundborg 1 specified a two sector general equilibrium model with fair wages and involuntary unemployment to study the effects of tax policy and unemployment benefits on employment resource allocation and tax incidence rather than involving in the debates of the effects of different tax policies the present paper will examine the optimal tax structure using the framework of such a model the primary question addressed is the following given that a wage tax may adversely affect after tax wages and employment while a commodity tax should not have such harmful effects how should the government impose taxes on labor and commodities to minimize the welfare loss of taxation it should be noted that the exercise here is not merely of academic interest it has important implications for policy making efficiency wage models were invented to better describe existence of involuntary unemployment with prevailing unemployment in most economy design of any tax policy should not neglect the influences of taxation on employment and resource allocation the model specified below differs from most efficiency wage models in two important respects first it explicitly introduces commodities demanded and labor supplied rather than wage income and work effort into an individual s utility function a two stage approach is used to show that this way of specifying utility provides the micro foundation of the shirking version of efficiency wage models especially the one used by pisauro 4 in which a worker chooses work effort to maximize expected utility second the one sector model used widely in the efficiency wage literature is extended to a two sector model by allowing for differences in the production methods used by the two sectors or industries 2 in addition to revealing how different tax policies

the importance of business owners in assessing the size of precautionary savings abstract not properly accounting for differences between business owners and nonbusiness owners in studies of household wealth can lead to erroneous conclusions about the significance of different saving motives using data from the panel study of income dynamics from the 1980s and 1990s we show that within samples of both business owners and non business owners the amount of precautionary savings with respect to labor income risk is modest and accounts for less than 10 of total household wealth previous large estimates of the size of precautionary balances resulted from pooling these two groups together such pooling is inappropriate given that business owners face higher labor risk and accumulate more wealth than non business owners for reasons unrelated to precautionary motives

granger causality real factor prices and employment a re appraisal with uk data this paper reports the results produced by applying tests for granger causality of post war u k real wage and employment data the results suggest that real wages granger cause employment with no feedback this result is robust to the inclusion of real materials prices the results are not robust to changes in the sample period real wages and employment appear independent with data up to 1977 4 the oscillations of real wages between 1976 and 1978 when a stern wage policy was implemented and dismantled are responsible for these different results this explains the contradictory results reported in previous studies

subsidies and crowding out a double hurdle model of fertilizer demand in malawi this article uses a double hurdle model with panel data from malawi to investigate how fertilizer subsidies affect farmer demand for commercial fertilizer the article controls for potential endogeneity caused by the nonrandom targeting of fertilizer subsidy recipients results show that on average 1 additional kilogram of subsidized fertilizer crowds out 0 22 kg of commercial fertilizer but crowding out ranges from 0 18 among the poorest farmers to 0 30 among relatively nonpoor farmers this indicates that targeting fertilizer subsidies to the rural poor is likely to maximize the contribution of the subsidy program to total fertilizer use

pricing a class of american and european path dependent securities path dependent securities depend on current and past values of underlying state variables consequently the usual backward evaluation technique is difficult to apply since state variable values existing earlier in real time are unknown this paper develops a series of propositions which makes possible the pricing of a certain class of both american and european versions of these path dependent securities

unemployment and the efficiency wage hypothesis there has been much recent discussion of the reasons why prices in certain markets and in particular in labour markets may not adjust to eliminate excess supply the absence of speedy adjustment of prices is an essential feature of the recent models of disequilibrium macroeconomics but for the most part no explanation for this absence is provided from within those models one explanation that has been around in the literature for some time and has been receiving increasing attention recently is the efficiency wage hypothesis initially applied to developing economies see leibenstein i957 it has more recently been adapted to developed economies by weiss i 980 and used in the context of a keynesian macroeconomic model by hart i 980 similar concepts have been applied to the credit market by stiglitz and weiss i98i the purpose of the present paper is to explore further the conditions under which the notion of an efficiency wage is applicable and can provide an explanation of involuntary unemployment the essential feature of the efficiency wage hypothesis is that the productivity of a firm s employees increases as their wage is increased at least over an economically relevant part of its range if the wage paid by the firm is denoted by w the number of employees by l and the productivity of each employee by p w where p w o then the effective labour force of the firm e can be represented by

canadian jobs and firm size do smaller firms pay less even after controlling for observable workers characteristics and for occupation and industry specific effects a substantial wage differential remains between large and small firms what underlies the remaining wage differential is unclear direct evidence on pension plan coverage and on lay off rates by firm size is inconsistent with the bad working conditions hypothesis the union avoidance hypothesis does not seem to explain an important portion o f the wage differential as suggested by efficiency wage models part of the remaining wage differential may be due to firms heterogeneity similarly perhaps large firms pay higher wages simply partly beca use they employ workers with more unobserved abilities because differen t explanations of the wage differential may lead to different policy implications determining the source of the wage firm size effect is an important question for future research

the impact of agricultural extension and roads on poverty and consumption growth in fifteen ethiopian villages this article investigates whether public investments that led to improvements in road quality and increased access to agricultural extension services led to faster consumption growth and lower rates of poverty in rural ethiopia estimating an instrumental variables model using generalized methods of moments and controlling for household fixed effects we find evidence of positive impacts with meaningful magnitudes receiving at least one extension visit reduces headcount poverty by 9 8 percentage points and increases consumption growth by 7 1 percentage points access to all weather roads reduces poverty by 6 9 percentage points and increases consumption growth by 16 3 percentage points these results are robust to changes in model specification and estimation methods

macroeconomic adjustment with segmented labor markets this paper analyzes the macroeconomic effects of fiscal and labor market policies in a developing economy with an informal sector and a heterogeneous work force a permanent reduction in government spending on nontraded goods leads in the long run to a deprecia tion of the real exchange rate a fall in the market clearing wage for unskilled labor an increase in output of traded goods and a lower stock of net foreign assets a permanent reduction in the minimum wage improves competitiveness and expands the formal sector the effect of changes in unemployment benefits are also analyzed q 1999 elsevier science

the pricing of default free interest rate cap floor and collar agreements the paper focuses on the valuation of caps floors and collars in a contingent claim framework under continuous time these instruments are interpreted as options on traded zero coupon bonds the bond prices themselves are used as the underlying stochastic variables this has the advantage that we end up with closed form solutions which are easy to compute special attention is devoted to the choice of the stochastic process appropriate for the price dynamics of the underlying zero coupon bonds the increased volatility of interest rates and the introduction of numerous variable rate instruments have led to a more intensive use of highly sophisticated risk hedging tools among them interest rate caps floors and collars have recently gained a growing popularity an interest rate cap is an agreement between the provider of the cap and a borrower to limit the borrower s floating interest rate to a specific level for a given period of time to be more precise the borrower selects a reference rate to hedge e g libor a period of time to hedge e g 5 years and the level of protection desired e g a ceiling of 200 basis points above the current level of the libor if the market rate exceeds the ceiling rate the cap provider will make payments to the buyer sufficient to bring his rate back to the ceiling when the market rate is below the ceiling no payment is made

the effect of import price changes on domestic inflation an empirical test of the ratchet effect note the possibility of downward rigidity of wages and prices has been considered in the literature at least since keynes general theory many argue that monopolistic forces such as oligopolies and unions respond to inflationary pressures by raising wages and prices but resist wage and price reductions l to the extent that these entities resist downward wage and price movements they contribute to the existence of a ratchet effect in which wages and prices behave asymmetrically the issue of a possible ratchet effect is particularly important in the context of international price movements commonly known as the mundell laffer hypothesis 2 the ratchet effect implies an upward bias in the response of domestic prices to changes in import prices consider the effect of an exchange rate movement on prices depreciation raises import prices thereby increasing the domestic price level the question is whether appreciation causes an equal downward movement in prices for example a 10 percent exchange rate depreciation followed by 10 percent appreciation would leave the exchange rate intact but may leave domestic prices higher than the original level if prices adjust asymmetrically throughout the world such an exchange rate movement would result in higher world prices despite the attention this issue has received in the theoretical literature little empirical work has been devoted to it in a discussion of the literature ahmad 1984 p 4 assumes the ratchet effect is significant and inflationary in empirical research sachs 1985 and feldman 1984 among others make the opposite assumption in the only paper devoted to empirical testing of the ratchet effect goldstein 1977 presents evidence that price movements are symmetric but his

labor contracts under asymmetric information when workers are free to quit this paper examines the impact of workers ability to quit on the performance of labor contracts between workers and privately informed firms while the need to induce workers to remain with the firm necessarily lowers total welfare the effect on employment levels is to reduce the magnitude of the inefficiency due to asymmetric information whether this inefficiency is under or overemployment the model predicts that employment distortions increase with the strength of lock in effects on workers a prediction which contrasts with the results of efficiency wage models and which may help in empirical testing of labor contract theory

involuntary unemployment and worker self selection abstract consider a firm that lacks information about the reservation wage or ability of any specific worker but is aware that workers with higher reservation wages tend to be more able on average we show that under a simple condition that the efficiency wage exceeds the lowest reservation wage the optimal hiring policy for the firm involves 1 no wage discrimination and 2 rationing of jobs when demand for its product is low the result also extends to the case where hours of work are variable provided each worker is most productive when working a strictly positive number of hours per week

on the optimal rate structure of an individual income tax what is the optimal rate structure of a personal income tax in the literature on optimal taxation this important question has been approached by introducing a linear income tax formula into a revised ramseyian model which takes into account both efficiency and equity objectives of taxation the assumption of a linear tax enables us to examine the degree of tax progression through the behavior of the average rate but it does not throw light on how the marginal rate should vary with income 1 lecture 13 a classic paper by mirrlees 7 which was later expounded on by atkinson and stiglitz 1 412 22 solves this problem by explicitly considering a general income tax schedule however both linear and general tax formulae provide little guide for policy making since in practice the tax rates are graduated by a bracket system that is the income scale is divided into segments or brackets and rates are applied only to the income in each bracket rates increase or decrease by small percentage points from one bracket to the next in order to avoid large and abrupt changes in tax burden as income rises the present paper attempts to demonstrate how we can easily transform a segment graduated tax system into a multiple linear system and then incorporate it into the standard optimum taxation model we then proceed to derive the conditions governing the optimal value of an upper or lower limit of a tax bracket and the marginal tax rate applied to the bracket combining these conditions together will enable us to infer what the optimal rate structure should be

commercialization of the small farm sector and multidimensional poverty abstract global poverty rates have declined considerably but the number of people living in extreme poverty remains high many of the world s poor are smallholder farmers agricultural commercialization meaning a shift from subsistence to more market oriented farming can play a central role in improving smallholder welfare previous studies evaluated the impact of agricultural commercialization on income poverty but whether income gains from commercialization are really used for satisfying basic needs was hardly analyzed up till now here we evaluate the effect of commercialization on income poverty as well as on the multidimensional poverty index that looks at deprivations in terms of education nutrition health and other dimensions of living standard using data from 805 farm households in kenya we estimate average treatment effects and also analyze impact heterogeneity with quantile regressions results show that commercialization reduces both income poverty and multidimensional poverty the magnitude of the income gains is positively correlated with income level meaning that market linkage support for marginalized farms may be needed to avoid rising inequality however the effect in terms of reducing basic needs deprivations is stronger for the poorest households suggesting that agricultural commercialization contributes effectively to achieving the sustainable development goals

efficiency wages deferred payments and direct incentives in agriculture empirical evidence from agricultural labor markets is consistent with efficiency wage theory and inconsistent with several alternative explanations according to this theory the higher wage or deferred payment benefits that direct hire growers pay relative to that of farm labor contractors is an efficiency wage growers use this extra compensation to lower their monitoring expenses and reduce shirking by workers copyright 2002 oxford university press

neighbors and extension agents in ethiopia who matters more for technology adoption improving agricultural productivity is seen as vital to economic growth in poor countries particularly in sub saharan africa where productivity growth has lagged behind that of other continents the focus has therefore been on new technologies particularly the adoption and diffusion of improved seed varieties and the increased use of fertiliser supported by investments in effective extension services it is important to understand how these new technologies spread and the effectiveness of extension services in this process

incentive compatible long term contracts and job rationing this article presents a model in which markets for long term contractual employment coexist with spot markets for labor assuming the absence of third party enforcement wage contracts are required to be incentive compatible as a consequence contract wages yield higher expected utility to the worker than spot market wages so that in equilibrium contractual long term jobs are rationed

agricultural technology adoption and household welfare measurement and evidence abstract previous studies on the adoption and impacts of improved crop varieties have relied on self reported adoption status of the surveyed households however in the presence of weak variety maintenance and poorly functioning seed certification system measurement errors in self reported adoption status can be considerable this paper investigates how such measurement errors can lead to biased welfare estimates using dna fingerprinting based varietal identification as a benchmark we find that misclassification in self reported adoption status is considerable with significant false negative and positive response rates we empirically show that such measurement errors lead to welfare estimates that are biased towards zero and substantially understate the poverty reduction effects of adoption while the empirical evidence suggests attenuation bias our theoretical exposition and simulations demonstrate that upward bias and sign reversal effects are also possible the results point to the need for improved monitoring of the diffusion process of improved varieties through innovative adoption data collection approaches to generate robust evidence for prioritizing and justifying investments in agricultural research and extension

dollar a day revisited the article presents the first major update of the international 1 a day poverty line proposed in world development report 1990 poverty for measuring absolute poverty by the standards of the world s poorest countries in a new and more representative data set of national poverty lines a marked economic gradient emerges only when consumption per person is above about 2 00 a day at 2005 purchasing power parity below this the average poverty line is 1 25 which is proposed as the new international poverty line the article tests the robustness of this line to alternative estimation methods and explains how it differs from the old 1 a day line

the importance of the savings device in precautionary savings empirical evidence from rural bangladesh we test if precautionary behavior in the consumption decisions of rural households differs across the forms of savings using monthly panel data from bangladesh we find that on average the savings device does not matter but that the effect of income on savings indeed depends on the savings device precautionary savings in the form of staple grain are relatively constant across income quartiles while nongrain precautionary savings vary across income quartiles previous studies which treat these two types of savings devices as fungible misdiagnose the reasons for and by extension the market failures behind a large percentage of the precautionary savings held by rural households

wage interdependence through decentralized bargaining abstract the idea that sector specific unions are influenced by the wages obtained by other unions has mainly been used to support the empirical observation that wages are highly correlated among industries the sources of wage interdependence can mainly be found in unions preferences in the nature of technology and in price and demand determination the presence of externalities and of strategic complementarity among unions leads to suboptimal equilibria which generates non desired inflation unemployment and possibly also trade balance deficit this enforces the idea that part of current unemployment can be eliminated by improving the cooperation between social actors

multiple expectational equilibria under monopolistic competition this paper shows that a monopolistically competitive economy with real investment can have multiple rational expectations equilibria one is associated with entrepreneurs optimistic expectations about future demand another with entrepreneurs pessimism it also shows that an optimistic expectational equilibrium pareto dominates a pessimistic equilibrium an investment subsidy can be beneficial both by reducing the original underinvestment distortion and by changing firms expectations from pessimistic to optimistic the most important assumption is increasing returns to scale and monopolistic competition makes increasing returns consistent with each producer s optimization

welfare impacts of improved chickpea adoption a pathway for rural development in ethiopia we analyse the impact of improved chickpea adoption on welfare in ethiopia using three rounds of panel data first we estimate the determinants of improved chickpea adoption using a double hurdle model we apply a control function approach with correlated random effects to control for possible endogeneity resulting from access to improved seed and technology transfer activities to instrument for these variables we develop novel distance weighted measures of a household s neighbours access to improved seed and technology transfer activities second we estimate the impact of area under improved chickpea cultivation on household income and poverty we apply a fixed effects instrumental variables approach where we use the predicted area under cultivation from the double hurdle model as an instrument for observed area under cultivation we find that improved chickpea adoption significantly increases household income while also reducing household poverty finally we disaggregate results by landholding to explore whether the impact of adoption has heterogeneous effects adoption favoured all but the largest landholders for who the new technology did not have a significant impact on income overall increasing access to improved chickpea appears a promising pathway for rural development in ethiopia s chickpea growing regions

efficiency wage models of unemployment keynesian economists hold it to be self evident that business cycles are characterized by involuntary unemployment but construction of a model of the cycle with involuntary unemployment faces the obvious difficulty of explaining why the labor market does not clear involuntarily unemployed people by definition want to work at less than the going wage rate why don t firms cut wages thereby increasing profits

online low price guarantees a real options analysis a common practice among large retailers is the low price guarantee rebating consumers if they find an identical product cheaper elsewhere this provides consumers with some level of comfort in their purchase decision a similar low price guarantee is provided by numerous service industries that allow reservation of capacity yet do not penalize the consumer for failure to keep that reservation examples include hotels and car rental given that a consumer is not required to keep the reservation they may make another reservation either at a competing firm or the same firm if future prices decline the increasing availability of pricing information on the internet affords consumers the opportunity to be more strategic in their purchasing behavior as consumers we are able to quickly and easily check prices from numerous service or goods providers the ease of price information potentially makes these guarantees very costly to the service or good provider we analyze the implied costs associated with these guarantees by making analogies to financial options motivation for this research comes from a large car rental firm dollar thrifty automotive group inc that considered offering a low price guarantee to all consumers that book a reservation though their website

the causes of increasing interindustry wage dispersion in the united states using establishment level data from a variety of sources this study documents and analyzes the consistent rise in interindustry wage dispersion in the united states between 1970 and 1987 the authors attribute about 60 of the rise in this measure of wage dispersion to competitive market factors such as changes in the demographic and occupational mix of industrial sectors they find however that noncompetitive factors also play an important part in this trend the most important noncompetitive factor is a strong link between the long term trends in industry wages and productivity growth which appears to stem largely from rent sharing behavior among industries

house prices development costs and the value of waiting abstract this paper demonstrates that new house prices can exceed direct development costs by considerable margins in competitive housing markets with finite price elasticities of demand and no restrictive land use regulation the premium reflects the value of the option to delay developing the marginal piece of undeveloped land competition amongst landowners reduces the option value relative to the standard open city framework but as long as undeveloped land is heterogeneous does not reduce it to zero calibrating a special case of the model to us data suggests that the premium is economically significant in addition to proving that prices can exceed costs without regulation this paper shows that the relationship between volatility and the rate of investment is more complicated than previously thought

a model of the natural rate of unemployment since the publication of edmund phelps volume the new macroeconomics has treated the labor market as a dynamic process of rational search by unemployed workers for available vacancies wages are viewed as at least potentially flexible though free contracting between workers and firms may lead to fixed wages in the short run imperfect information is a crucial element of the theory for it implies both a need for contracting and a need for rational search rather than simple market clearing in each period a positive rate of frictional unemployment may exist in equilibrium denoted as the natural rate this unemployment is due to the frictions in the search process and imperfections in information rather than to any deficiency in aggregate demand milton friedman defined the natural rate as the level that would be ground out by the walrasian system of general equilibrium equations provided there is embedded in them the actual structural characteristics of the labor and commodity markets including market imperfections stochastic variability in demands and supplies the cost of gathering information about job vacancies and labor availabilities the costs of mobility and so on p 8 this paper reexamines the micro foundations of the natural rate in a model of labor market equilibrium in which turnover flows and imperfect information are explicitly considered workers may quit their current jobs to enter the unemployment pool in order to search among available vacancies for a more preferred position firms economize on turnover by an appropriate wage policy

an efficiency wage model with explicit monitoring abstract this paper develops an efficiency wage model of involuntary unemployment in a small open economy which uses two factors to produce three goods one of which is non traded monitoring aimed at reducing shirking by workers in all industries the analysis shows how a tariff on imports may lower employment but paradoxically raise social welfare at the same time as the paper also demonstrates the optimal policy combination includes not only taxes on capital and monitoring as well as a subsidy on employment but also despite the small country assumption a tax on consumption

the impacts of hybrid maize seed on the welfare of farming households in kenya this paper explores the impacts of hybrid maize adoption on the welfare of farming households in kenya we use a four year panel dataset to estimate the effects of hybrid seed use on four indicators of household welfare namely income assets inequality and poverty results show that use of hybrid seed not only contributes to higher annual income but also to raising the value of assets possibly reflecting longer term welfare effects further we find that use of hybrid seed reduces the depth of poverty and that the amount planted reduces inequality as expected impacts differ between major and minor maize growing areas of the country maize farmers who do not use hybrid seed are clearly disadvantaged this calls for continued public and private investments in the infrastructure and policy process that supports a competitive liberalized seed industry and improved access of smallholder farmers to well adapted affordable hybrids

profit sharing risk sharing and firm size implications of efficiency wages by taking account of output fluctuations this paper constructs a synthesis of profit sharing and efficiency wage models to highlight the role of the risk attitudes of the firm and its employees we show contrary to the traditional efficiency wage theory that in a profit sharing economy unemployment is no longer a necessary device to induce work effort and consequently the labor market equilibrium may be characterized by full employment such a result is more likely to be true when the economy is characterized by small sized firms in addition we also provide a preliminary sketch of the situations in which the firm chooses a profit sharing program or a fixed wage one and discuss how a firm determines its pay parameters and employment in response to output fluctuations

an exogeneity test for a simultaneous equation tobit model with an application to labor supply a test of weak exogeneity in the simultaneous equation tobit model is proposed and illustrated using a female labour supply model estimated using cross section data the test statistic can be simply output from any standard tobit maximum likelihood package and is asymptotically efficient the procedure provides consistent estimators for the simultaneous tobit model whose asymptotic covariance matrix is a simple extension of the usual tobit formula we also provide the lagrange multiplier test of weak exogeneity this abstract was borrowed from another version of this item

path dependent options the case of lookback options lookback options are path dependent contingent claims whose payoffs depend on the extrema of a given security s price over a certain period of time using probabilistic tools we derive explicit formulas for various european lookback options and provide some results about their american counterparts

consumption risk technology adoption and poverty traps evidence from ethiopia much has been written on the determinants of input and technology adoption in agriculture with issues such as input availability knowledge and education risk preferences profitability and credit constraints receiving much attention this paper focuses on a factor that has been less well documented the differential ability of households to take on risky production technologies for fear of the welfare consequences if shocks result in poor harvests building on an explicit model this is explored in panel data for ethiopia historical rainfall distributions are used to identify the counterfactual consumption risk controlling for unobserved household and time varying village characteristics it emerges that not just ex ante credit constraints but also the possibly low consumption outcomes when harvests fail discourage the application of fertilizer the lack of insurance causes inefficiency in production choices