periodic review and continuous ordering abstract many inventory control studies consider either continuous review and continuous ordering or periodic review and periodic ordering mixtures of the two are hardly ever studied however the model with periodic review and continuous ordering is highly relevant in practice as information on the actual inventory level is not always up to date while making ordering decisions this paper will therefore treat this model assuming zero fixed ordering costs and allowing for a non negative lead time and a general demand process we first consider a one period decision problem without salvage cost for inventory remaining at the end of the period in this setting we derive a base line optimal order path described by a simple newsvendor solution with safety stocks increasing towards the end of a review period we then show that for the general multi period problem the optimal policy in a period is to first arrive at this path by not ordering until the excess buffer stock from the previous review period is depleted then follow the path by continuous ordering and stop ordering towards the end to limit excess stocks for the next review period an important managerial insight is that typically no order should be placed at a review moment although this may seem intuitive and is also the standard assumption in periodic review models we illustrate that adhering to the optimal ordering path instead can lead to cost reductions of 30 60 percent compared to pure periodic ordering

investing in farmers the impacts of farmer field schools in relation to integrated pest management public policy in developing countries has failed to invest in educating farmers on how to deal with variable agro ecosystems and a changing world here we present an assessment of a participatory training approach in changing crop protection by farmers from chemically dependent to more sustainable practices in line with the tenets of integrated pest management ipm we review the evidence from the studies on an educational investment designed to capacitate farmers to apply ipm and discuss these data in the light of an on going policy debate concerning cost effectiveness the results indicate substantial immediate and developmental benefits of participation in farmer field schools

a dynamic inventory model with periodic auditing consider a single item periodic review stationary inventory model with stochastic demands proportional ordering costs and convex holding and shortage costs where shortages are backordered and veinott s well known terminal condition holds orders can be scheduled for any period but the actual inventory level is determined every t periods through an audit this leads to a dynamic programming model where stage n contains periods n 1t 1 through nt for both discounted and averaging criteria a simple rule optimally describes the orders for the t periods of a stage as a function of the state beginning inventory level and the cumulative t period order the latter is optimally determined by a base stock policy with two base stock levels one for the final stage another for the rest the horizon may be finite or infinite methods are presented for computing optimal policies together with bounds on the costs of suboptimal myopic policies models with proportional costs and continuous demands are studied in detail computational experiments indicate that myopic policies perform quite well for such models the selection of a best review period t is covered briefly applications of our model include just in time settings where audit decisions play a negligible role

a theory of real wage growth in ldcs abstract a general equilibrium framework is presented to explain a variety of developmental experiences the demand side is modelled by assuming a system of preferences that incorporate engel s law in a stark way the framework explains why poverty might be impervious to industrial progress in some countries it also explains why countries which have been able to boost the exports of manufactured goods have been more successful in raising real wages in their economies than countries which have continued to export primary goods the framework indicates how the initial conditions in terms of the level and distribution of wealth influence the growth of real wages in an economy

the optimal frozen period in a dynamic production model abstract we consider a periodic auditing model for manufacturers in a supply chain who observe stochastic demand proportional holding expedited ordering costs and setup cost customer demand for a component can arrive in any period but the procurement quantities are determined every t periods which is defined as a frozen period the demand forecasts are updated every period as more information becomes available from the marketplace this paper studies a forecast order policy and compares it with the optimal order policy our objective is to determine the optimal length of a frozen period and the safety stock in a frozen period such that the expected total cost per unit of time is minimized

an inventory model embedded in designing a supply contract to reduce lead time and its variability modern supply and transportation contracts often specify the frequency of and volume available for future deliveries in advance even when final demand is somewhat uncertain yano and gerchak yano c a y gerchak 1989 transportation contracts and safety stocks for just in time deliveries manufacturing and oper management 2 314 330 we explore the joint optimization of contract parameters and inventory control policy in such environments we first model and derive the optimal periodic review inventory policy corresponding to a given supply contract which generates piecewise linear convex ordering costs the optimal policy has two critical levels and there is a range of stock levels for which the quantity ordered equals the contract volume to numerically compute the critical levels we model consecutive inventory levels as a markov chain whose steady state distribution is used to compute the holding shortage and transportation costs we then use the

analysis of supply contracts with quantity flexibility this paper explores a class of supply contracts under which a buyer receives discounts for committing to purchases in advance the further in advance the commitment is made the larger the discount as time rolls forward the buyer can increase the order quantities for future periods of the rolling horizon based on updated demand forecast information and inventory status however the buyer pays a higher per unit cost for the incremental units such contracts are used by automobile and contract manufacturers and are quite common in fuel oil and natural gas delivery markets we develop a finite horizon dynamic programming model to characterize the structure of the optimal replenishment strategy for the buyer we present heuristic approaches to calculate the order volume in each period of the rolling horizon finally we numerically evaluate the heuristic approaches and draw some managerial insights based on the findings

whether crop diversification is a desired strategy for agricultural growth in bangladesh abstract this study aimed at examining the merit of crop diversification as a strategy for agricultural growth in bangladesh specifically the existence of economies of diversification scale economies and diversification efficiencies at the farm level were examined using a stochastic input distance function approach the results reveal strong evidence of diversification economies amongst most crop enterprises except the combination of modern rice and modern wheat enterprises ray economies of scale exist in bangladeshi cropping system also significant are efficiency gains made from diversification among cropping enterprises the key policy implication is that crop diversification should be a desired strategy for agricultural growth in bangladesh development of the rural infrastructure is also essential as this will not only improve technical efficiency but may also synergistically promote crop diversification by opening up opportunities for technology diffusion marketing storage and resource supplies

why does asset inequality affect unemployment a study of the demand composition problem abstract this paper is devoted to a general equilibrium analysis of the relationship between the inequality in asset holdings and the aggregate levels of output and employment in a developing economy since luxuries and basic goods compete for the use of the same scarce resources unemployment is concieved as a mechanism whereby the market demand for basic goods can be limited to a sufficiently low level so that the high demand for luxuries can be met the ambiguous effects of capital accumulation on employment are also examined

the optimal review period in a dynamic inventory model consider a single item periodic review infinite horizon undiscounted inventory model with stochastic demands proportional holding and shortage costs and full backlogging orders can arrive in every period and the cost of receiving them is negligible as in a jit setting every t periods one observes the current stock level and orders deliveries for the next t periods thus incurring a fixed setup cost the goal is to find a review period t and an ordering policy that minimize the long run expected average cost per period flynn and garstka flynn j s garstka 1990 a dynamic inventory model with periodic auditing opns res 38 1089 1103 characterize an optimal ordering policy when t is fixed and study a myopic policy whose cost is often close to the optimal cost this paper covers the problem of selecting t we prove an optimal review period t exists characterize its properties and present methods for its computation we also study an approximation to t based on the myopic policy of ou

an effective heuristic for the review period in an inventory model with staggered deliveries and normal demands abstract consider a single item periodic review infinite horizon undiscounted inventory model with stochastic demands proportional holding and shortage costs and full backlogging orders can arrive in every period and the cost of receiving them is negligible as in jit every t periods one audits the stocks and chooses a delivery schedule for each of the next t periods thus incurring a fixed audit cost and when one schedules actual deliveries a fixed order cost the problem is to find a review period t and an ordering policy minimizing the average cost an earlier article developed an algorithm for computing an optimal t and undertook a numerical study to evaluate various approximations assuming normal demands we characterize the asymptotic behavior for large of the optimal t and establish the asymptotic optimality of a heuristic calculable on a spreadsheet a numerical study indicates that patterns established here for large hold for above 2

smart policies to reduce pesticide use and avoid income trade offs an agent based model applied to thai agriculture abstract policy makers in developing countries need better evidence of how changes in pesticide regulation would affect pesticide reduction and farm incomes but there are very few modeling tools that can provide such information the present study develops a new model based on mathematical programming based multi agent system mpmas a simulation software that allows assessing ex ante the impact of alternative pesticide use reduction strategies including combinations of pesticide taxes the introduction of integrated pest management a price premium for safe agricultural produce and subsidies for biopesticides the model is parameterized with farm and plot level data from northern of thailand where the adoption of high value cash crops has been accompanied by a rapid increase in synthetic pesticide use simulation results suggest that a pesticide tax alone has little effect on synthetic pesticide use a smart policy package combining integrated pest management a progressive pesticide tax based on toxicity and subsidies lowering the price of biopesticides can reduce average use of hazardous pesticides by 34 over current levels without adverse effects on the average farm income

agricultural diversification and integrated pest management in bangladesh we study factors associated with a shift toward diversified high valued vegetable crops and the incentives associated with the use of ipm methods for vegetable producers in bangladesh the primary objective is to measure how ipm technologies affect the crop and technology choices of low income rice farmers a three season household optimisation model is used to study crop and technology choice under price and yield uncertainty the model is parameterised using data from vegetable farms and experimental ipm trials conducted in bangladesh simulation results show that access to ipm technology and ipm availability combined with access to credit increase household welfare and lead to higher rates of vegetable adoption off farm employment opportunities work against vegetable cultivation and ipm use by risk averse farmers implications for policy and extension efforts are highlighted

education democracy and growth abstract this note presents a model of endogenous growth where redistribution determined by a political equilibrium is in the form of public education it is shown that there need not be a negative relationship between growth and redistribution as public education increases the level of human capital in the conomy and at the same time tends to produce a more even income distribution

agricultural technology adoption and poverty reduction a propensity score matching analysis for rural bangladesh this study aims at shedding some light on the potential impact of agricultural technology adoption on poverty alleviation strategies it does so through an empirical investigation of the relationship between technological change of the green revolution type and wellbeing of smallholder farm households in two rural bangladeshi regions as technology adoption is not randomly assigned but there is self selection into treatment the paper tackles a methodological issue in assessing the causal effect of technology on farm household wellbeing through the non parametric p score matching analysis it pursues a targeted evaluation of whether adopting a modern seed technology causes resource poor farmers to improve their income and decrease the propensity to fall below the poverty line it finds a robust and positive effect of agricultural technology adoption on farm household wellbeing suggesting that there is a large scope for enhancing the role of agricultural technology in directly contributing to poverty alleviation 2006 elsevier ltd all rights reserved

farmer training in off season vegetables effects on income and pesticide use in bangladesh the cultivation of crops outside the regular cropping calendar when supply is low and prices are high can give farmers better profits and consumers more choice however off season production may increase pesticide risk if crops are more affected by pests and diseases and farmers do not handle pesticides correctly this study quantified the effect of training in off season tomato production on the income and pesticide use of smallholder vegetable farmers in southwestern bangladesh the study uses farm level data from 94 trained and 151 non trained farm households and applies propensity score matching and inverse probability weighting to correct for selection bias for the average smallholder vegetable farmer training increased net household income by about 48 we found that 31 of the trained farm households who had initially adopted the technology continued its use in the second year but farm households who discontinued using the technology also experienced significant income gains from the training there was a significant increase in pesticide use 56 and although there was an improvement in pesticide handling practices trained farmers may have been more exposed to pesticide health risk the policy implication is that while off season vegetable production can create dramatic income improvements it is important to emphasize safe and sustainable pest management methods as part of policies promoting it

an evaluation of the swedish system of active labour market programmes in the 1990s we investigate the presence of short and long term effects from joining a swedish labor market program vis a vis more intense job search in open unemployment overall the impact of the program system is found to have been mixed joining a program has increased employment rates among participants a result robust to a misclassification problem in the data on the other hand it has also allowed participants to remain significantly longer on unemployment benefits and more generally in the unemployment system this being particularly the case for those entitled individuals entering a program around the time of their unemployment benefits exhaustion

are there increasing returns to pollution abatement empirical analytics of the environmental kuznets curve in pesticides abstract according to the environmental kuznets curve ekc hypothesis economic growth and the reduction of environmental degradation are compatible goals an inverted u shaped relationship between economic performance and environmental pollution suggests that empirically an economy is associated with smaller levels of pollution after some threshold income point one potential explanation for the empirical evidence of an ekc is increasing returns to pollution abatement where the abatement efficiency rises with an increase in the scale of abatement doubling the clean up efforts more than doubles the abatement of pollution as this efficiency gain makes abatement less expensive pollution might fall as more abatement is undertaken this study tests the hypothesis that there are increasing returns to abating pollution empirical evidence on environmental risks in the us agricultural sector since 1970 support the existence of increasing returns in addition i estimate the productivity of pollution abatement using refined empirical productivity measurement methods and explicitly control the level of technology the results show the importance of including an environmental productivity variable in the ekc framework

macrodynamic adjustment mechanisms in a dual semi industrialized economy abstract the interplay between agriculture and the rest of the economy and the importance of the income distribution have been central to the macroeconomic analyses of semi industrialized economies a macrodynamic model is developed to investigate the adjustment mechanisms in the medium run it is shown how the roles of agriculture and income distribution depend on the macroeconomic situation and how the medium run adjustments may differ from short run effects

the impact of improved maize varieties on poverty in mexico a propensity score matching approach summary this study examines the adoption of improved maize germplasm in oaxaca and chiapas in mexico it employs a propensity score matching approach to analyze the impact of the adoption of improved maize varieties on household income and poverty reduction using cross sectional data of 325 farmers from the two regions the findings reveal a robust positive and significant impact of improved maize variety adoption on farm household welfare measured by per capita expenditure and poverty reduction specifically the empirical results suggest that adoption of improved maize varieties helped raise household per capita expenditure by an average of 136 173 mexican pesos thereby reducing their probability of falling below the poverty line by roughly 19 31

a periodic review replenishment model with a refined delivery scenario abstract this paper considers a single item replenishment problem where every n periods the buyer plans for the quantity delivered for each upcoming period assuming that demand not filled immediately is backlogged we suggest that the quantity delivered in the immediately upcoming period be of any size and the quantity delivered in each of the subsequent n 1 periods be equal to or smaller than a fixed quantity q we derive the average cost per n periods and compute the optimal order up to level for the proposed replenishment policy next assuming a fixed cost for reviewing inventory and planning deliveries we obtain the optimal n by minimizing the expected cost per period finally the optimal q can also be determined the proposed periodic review policy is easy to implement

agricultural pesticides and land use intensification in high middle and low income countries abstract we study levels and trends in agricultural pesticide use for a large cross section of countries using fao data for the period 1990 2009 our analysis shows that a 1 increase in crop output per hectare is associated with a 1 8 increase in pesticide use per hectare but that the growth in intensity of pesticide use levels off as countries reach a higher level of economic development however very few high income countries have managed to significantly reduce the level of intensity of their pesticide use because decreases in insecticide use at higher income levels are largely offset by increases in herbicide and fungicide use the results also show very rapid growth in the intensity of pesticide use for several middle income countries such as brazil mexico uruguay cameroon malaysia and thailand complementing our analysis with data from the rotterdam convention on prior informed consent pic we show that hazardous pesticides covered in the pic procedure are more weakly regulated in lower than in higher income countries we discuss the policy challenges facing developing countries with a rapid growth in pesticide use and recommend a four pronged strategy including an environmental tax on pesticides with revenues allocated to long term investments in awareness building the development of integrated crop management methods and the setting of food safety standards the interactions between these measures should help contribute to the effectiveness of the overall strategy package

valuing social sustainability in agriculture an approach based on social outputs shadow prices abstract interest in sustainability has gained ground among practitioners academics and policy makers due to growing stakeholders awareness of environmental and social concerns this is particularly true for agriculture however relatively little research has been conducted on the quantification of social sustainability and the contribution of social issues to the agricultural production efficiency this paper proposes a framework based on state contingent outputs to compute shadow prices of social outputs our methodological approach is based on the directional distance function and illustrated using a farm level dataset from a sample of catalan arable crop farms in 2015 our results indicate that in the sample of 180 farms included in the analysis efficiency scores are relatively high for the three alternative states of the nature considered in our state contingent analysis in addition our findings show that social outputs shadow prices are positive indicating that producing more social outputs is considered as great value to the farm for the efficient farms the social outputs shadow prices are contingent upon on the state of nature in a way that social outputs shadow prices increase with the improvement in crop growth conditions these results have implications in terms of eu farm payment redistribution

social articulation as a condition for equitable growth abstract a formal model is developed to establish the structural conditions that result in growth being progressive or regressive on the personal distribution of income these conditions include 1 intersectoral investment priorities between wage goods and luxuries and 2 the state of the levels and distribution of incomes which determines the social origin of demand for different sectors of the economy the particular combinations of investment and income structures that result in equalizing social articulation or unequalizing growth social disarticulation are derived we show empirically that the structural conditions that allowed rapid but unequalizing growth in brazil between 1968 and 1977 were those of social disarticulation

a note on social articulation abstract de janvry and sadoulet 1983 present a model of unequalizing growth and the closure rule of the model is discussed in this note it is shown that income distribution in the model is determined by the market clearing mechanism in the wage goods market and how the condition for social articulation is related to the excess demand function on the wage goods market

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

growth distribution and sectoral heterogeneity reading the kaleckians in latin america abstract the aim of this paper is to explore a parallelism between two episodes in the history of economic thought in order to suggest that the interaction between them can contribute to the research on kaleckian growth and distribution models first a brief summary of the theoretical development from steindl s stagnationist claims to the debate about demand regimes is offered then a more detailed account is provided of the latin american debate that began with furtado s stagnationist claims and resulted in the formulation of models of social articulation and disarticulation finally an analytical classification of kaleckian and latin american growth and distribution models is provided indicating the way in which sectoral heterogeneity and demand composition can act as a plausible link between growth and distribution

economic impact of direct marketing and contracts the case of safe vegetable chains in northern vietnam abstract the paper investigates the respective impacts on incomes of contractual arrangements direct sales and spot marketing for safe vegetable farmers in northern vietnam it is based on a survey of 137 peri urban vegetable farmers that was analyzed using different econometric methods to correct selection biases direct sales and contractual arrangements have a significant positive impact on income compared to spot marketing contracts have less impact on income compared to direct sales it is recommended that policies be formulated to stimulate direct dealings between farmers and consumers which enhance consumer confidence in terms of quality and translate into higher farmer income than anonymous exchanges or contracts

food aid targeting in ethiopia a study of who needs it and who gets it abstract the need for systematic empirical analysis of food aid targeting and impacts is overwhelming especially given the large numbers of people concerned and volume of funds allocated to the problem of feeding ethiopia s food insecure this research examines the efficiency of food aid targeting in rural ethiopia based on empirical evidence from a nationally representative survey of 4166 farm households a key finding of the study is that there is no significant association between household food insecurity vulnerability and food aid receipts a result of high errors of exclusion and inclusion at both the wereda and household levels four factors are identified as causes of the high level of targeting error 1 the primary beneficiaries of food aid programs are found to be households at the extremes in terms of food availability those with the least and those with the most food available 2 a disproportionate number of female and aged heads of households received food aid irrespective of their food needs 3 an inability of the food aid system to reach households outside of the historically deficit areas and 4 a disproportionate concentration of food aid in the region of tigray

supply chain differentiation contract agriculture and farmers marketing preferences the case of sweet pepper in thailand there is an emerging body of literature analyzing how smallholder farmers in developing countries can be linked to modern supply chains however most of the available studies concentrate on farm and farmer characteristics failing to capture details of institutional arrangements between farmers and traders moreover farmers preferences have rarely been considered here we address these gaps by analyzing different market channels for sweet pepper in thailand using data from a survey and choice experiment with farmers we find that there is a general preference for marketing options that do not involve a contract additional provision of inputs and credit can increase the attractiveness of contracts yet the most important factor for farmers is to personally know the buyer they deal with which may be related to issues of trust some policy implications are discussed

food aid dependency in northeastern ethiopia myth or reality summary food aid dependency among ethiopian farmers frequently is claimed with serious policy impacts this article explores this assertion with reference to south wollo ethiopia one of the country s largest recipients of food aid it uses household economic and ethnographic data from the 1999 2000 and 2002 03 droughts when food aid imports were very high by examining patterns of food aid distribution and resource allocation among groups of food aid recipients and non recipients the article suggests that food aid has not encouraged dependency like behaviors it suggests that few farmers would be foolhardy enough to significantly alter their actions since food aid delivery is too uncertain and poorly timed

pesticides productivity and farmer health a philippine case study health is recognized as one of the most important components of the human capital of rural people in developing countries there is a growing body of literature showing the productivity effects of health associated with nutrition e g bliss and stern 1978 strauss 1986 deolalikar 1988 pitt rosenzweig and hassan 1990 in this literature the productivity effects of health are inferred either by correlating health indicators with wages or by including health indicators in an agricultural production function the human capital literature also has demonstrated that farmer education plays an important role in the allocative and technical efficiency of farmers welch 1970 schultz 1975

impact of cooperatives on smallholders commercialization behavior evidence from ethiopia this article examines the impact of marketing cooperatives on smallholder commercialization of cereals using detailed household data in rural ethiopia we use the strong government role in promoting the establishment of cooperatives to justify the use of propensity score matching to compare households that are cooperative members to similar households in comparable areas without cooperatives the analysis reveals that although cooperatives obtain higher prices for their members they are not associated with a significant increase in the overall share of cereal production sold commercially by their members however these average results hide considerable heterogeneity across households in particular we find that smaller farmers tend to reduce their marketed output as a result of higher prices whereas the opposite is true for larger farmers

to spray or not to spray pesticides banana exports and food safety how governments regulate food safety and environmental protection including pesticide residue levels has important implications for trade the world trade organization wto ministerial held in doha qatar in november 2001 included statements on standards and their impact on market access for developing countries these issues will continue to be important in trade policy dialogues it is assumed and evidence from recent analysis confirms that food safety standards can affect the ability of agricultural producers to meet regulatory standards set by importing countries the authors explore a fundamental question in food safety and environmental standards do regulations on pesticide have an effect on trade they examine regulatory data from 11 oecd importing countries and trade data from 19 exporting countries the results suggest that a 10 percent increase in regulatory stringency tighter restrictions on the pesticide chlorpyrifos leads to a decrease in banana imports by 14 8 percent this represents a significant impact on trade and affect prospects of developing countries who continue to rely on exports of agricultural commodities such as bananas the findings also suggest that the lack of consensus on international standards and divergent national regulations on pesticides is costly for example the authors estimate that if the world were to adopt a standard at a level of regulatory stringency suggested by codex the body charged with setting global standards in this area in contrast with one set at the level in place in the european union there would be a u s 5 3 billion loss in world exports

the diffusion of new agricultural technologies the case of crossbred cow technology in tanzania the recent literature on agricultural technology adoption shows that diffusion of new technologies varies significantly across space and time furthermore puzzles exist about why some seemingly profitable technologies are not adopted especially in livestock production we employ a hazard or duration function to explain diffusion of crossbred cow technology in a unique sample of tanzania farmers a farmer s adoption of crossbred technology depends positively on the proximity of his farm to other users on his schooling and on his access to credit and contact with extension agents

sectoral balance in development a survey abstract this paper surveys the literature on sectoral balance to see how sectoral imbalances can retard economic development it examines definitions of sectors and balance provides background facts theories and planning tools reviews the debate on balanced growth and surveys two sector models of agriculture industry consumption investment and luxury basics interaction the open economy and the role of service nonmarket and unproductive sectors it argues that the examination of important development issues requires multisectoral analysis incorporating the insights of several of these models and that alternative models with different structural characteristics deserve attention

disarticulation and human welfare in less developed countries disarticulation refers to the juxtaposition of economic sectors with different levels of development and productivity disarticulation is hypothesized to have a negative effect on social well being net of economic development because it inhibits the spread effects generally thought to be associated with economic growth findings are in accord with this hypothesis although the relationship is complex the strongest effects of disarticulation are found among the poorest nations the concept of disarticulation opens a new and promising avenue of research that may help to resolve contradictory findings of recent research on the political economy of growth

inventory performance under staggered deliveries and autocorrelated demand production plans often span a whole week or month even when independent production lots are completed every day and service performance is tallied daily such policies are said to use staggered deliveries meaning that the production rate for multiple days are determined at a single point in time assuming autocorrelated demand and linear inventory holding and backlog costs we identify the optimal replenishment policy for order cycles of length p with the addition of a once per cycle audit cost we optimize the order cycle length p via an inverse function approach in addition we characterize periodic inventory costs availability and fill rate as a consequence of staggering deliveries the inventory level becomes cyclically heteroskedastic this manifests itself as ripples in the expected cost and service levels nevertheless the cost optimal replenishment policy achieves a constant availability by using time varying safety stocks this is not the case with suboptimal constant safety stock policies where the availability fluctuates over the cycle

can minimum wages cause a big push evidence from indonesia big push models suggest that local product demand can create multiple labor market equilibria one featuring high wages formalization and high demand and one with low wages informality and low demand i demonstrate that minimum wages may coordinate development at the high wage equilibrium using data from 1990s indonesia where minimum wages increased in a varied way i develop a difference in spatial differences estimator which weakens the common trend assumption of difference in differences estimation reveals strong trends in support of a big push formal employment increases and informal employment decreases in response to the minimum wage local product demand also increases and this formalization occurs only in the non tradable industrializable industries suggested by the model while employment in tradable and non industrializable industries also conforms to model predictions

the impact of a food security program on household food consumption in northwestern ethiopia a matching estimator approach abstract with the financial support from various development partners ethiopia has designed and implemented several programs to improve household food security yet food insecurity is still a major challenge to several millions of people in the country and it is questionable whether the different food security programs implemented over the past years have been successful using a propensity score matching method to control for pre intervention differences this study examined the impact on household food calorie intake of an integrated food security program ifsp which had been implemented in northwestern ethiopia by two non governmental organizations as a case study the estimated results provide evidence that ifsp has a positive and statistically significant effect on food calorie intake in particular ifsp has raised physical food calorie intake by 30 among the beneficiary households however we also found that ifsp has differential impact depending on family size landownership and gender of head of household overall the paper provides evidence that supporting integrated food security programs is important to improve food security in rural areas

determinants of food security in southern ethiopia at the household level in the early 1980s a paradigm shift occurred in the field of food security following amartya sens 1981 claims that food insecurity is more of a demand concern affecting the poor s access to food than a supply concern affecting availability of food at the national level despite the wide acceptance of sen s thinking many controversies including the relative importance of supply side versus demand side variables in causing and solving food insecurity have remained in academic and policy circles this study develops a recursive household food security model within the framework of consumer demand and production theories following singh et al 1986 and parses out the relative importance of supply side versus demand side variables in determining household food security in southern ethiopia based on results of a test of full reduced model and the magnitude of changes in conditional probabilities of food security we conclude that the supply side variables are more powerful determinants of food security than the demand side variables