assortment planning and inventory decisions under stockout based substitution we present an efficient dynamic programming algorithm to determine the optimal assortment and inventory levels in a single period problem with stockout based substitution in our model total customer demand is random and comprises fixed proportion of customers of different types customer preferences are modeled through the definition of these types each customer type corresponds to a specific preference ordering among products a customer purchases the highest ranked product according to his type if any that is available at the time of his visit to the store stockout based substitution we solve the optimal assortment problem using a dynamic programming formulation we establish structural properties of the value function of the dynamic program that in particular help to characterize multiple local maxima we use the properties of the optima to solve the problem in pseudopolynomial time our algorithm also gives a heuristic for the general case i e when the proportion of customers of each type is random in numerical tests this heuristic performs better and faster than previously known methods especially when the mean demand is large the degree of substitutability is high the population is homogeneous or prices and or costs vary across products

sustainable development and corporate performance a study based on the dow jones sustainability index the goal of this paper is to examine whether business performance is affected by the adoption of practices included under the term corporate social responsibility csr to achieve this goal we analyse the relation between csr and certain accounting indicators and examine whether there exist significant differences in performance indicators between european firms that have adopted csr and others that have not the effects of compliance with the requirements of csr were determined on the basis of firms included in the dow jones sustainability index djsi and specific accounting indicators were applied to measure performance for the purposes of this study we selected one group of firms belonging to the djsi and another comprised of firms quoted on the dow jones global index djgi but not on the djsi the sample was made up of two groups of 55 firms studied for the period 1998 2004 empirical analysis supports the conclusion that differences in performance exist between firms that belong to the djsi and to the djgi and that these differences are related to csr practices we find that a short term negative impact on performance is produced

the value relevance of reputation for sustainability leadership this study investigates whether the market valuation of the two summary accounting measures book value of equity and net income is higher for firms with reputation for sustainability leadership when compared to firms that do not enjoy such reputation the results are interpreted through the lens of a framework combining signalling theory and resource based theory according to which firms signal their commitment to sustainability to influence the external perception of reputation a firm s reputation for being committed to sustainability is an intangible resource that can increase the value of a firm s expected cash flows and or reduce the variability of its cash flows our findings are according to expectations and show that the net income of firms with good sustainability reputation has a higher valuation by the market when compared to their counterparts

revisiting the role of education for agricultural productivity while the majority of micro studies finds that rural education increases agricultural productivity various recent cross country regressions analysing the determinants of agricultural productivity were only able to detect insignificant or even surprising negative effects of schooling in this paper we argue and show that this failure to find a positive impact of education in the international context is rather a data problem related to the use of enrolment and literacy indicators using a panel of 95 developing and middle income countries from 1961 to 2002 together with the newest version of the barro lee educational attainment dataset we show that education indeed has a highly significant positive effect on agricultural productivity which is robust to changes in the control variables and in the econometric methods applied distinguishing between different levels of education further reveals that only primary and secondary schooling have significant positive impacts while tertiary education remains insignificant finally the effect of education is estimated separately for countries with different income levels results indicate that the coefficient of the education variable remains insignificant for countries from the poorest three income quintiles while it is positive and highly significant for the richest two quintiles this finding can be interpreted as support for the prominent argument claiming that education leads to higher agricultural productivity only in the presence of rapid technical change where education will help farmers to adjust more readily to the new opportunities

estimation of consumer demand with stock out based substitution an application to vending machine products the occurrence of temporary stock outs at retail is common in frequently purchased product categories available empirical evidence suggests that when faced with stock outs consumers are often willing to buy substitute items an important implication of this consumer behavior is that observed sales of an item no longer provide a good measure of its core demand rate sales of items that stock out are right censored while sales of other items are inflated because of substitutions knowledge of the true demand rates and substitution rates is important for the retailer for a variety of category management decisions such as the ideal assortment to carry how much to stock of each item and how often to replenish the stock the estimated substitution rates can also be used to infer patterns of competition between items in the category in this paper we propose methods to estimate demand rates and substitution rates in such contexts we develop a model of customer arrivals and choice between goods that explicitly allows for possible product substitution and lost sales when a customer faces a stock out the model is developed in the context of retail vending an industry that accounts for a sizable part of the retail sales of many consumer products we consider the information set available from two kinds of inventory tracking systems in the best case scenario of a perpetual inventory system in which times of stock out occurrence and cumulative sales of all goods up to these times are observed we derive maximum likelihood estimates mles of the demand parameters and show that they are especially simple and intuitive however state of the art inventory systems in retail vend ing provide only periodic data i e data in which times of stock out occurrence are unobserved or missing for these data we show how the expectation maximization em algorithm can be employed to obtain the mles of the demand parameters by treating the stock out times as missing data we show an application of the model to daily sales and stocking data pooled across multiple beverage vending machines in a midwestern u s city the vending machines in the application carry identical assortments of six brands since the number of parameters to be estimated is too large given the available data we discuss possible restrictions of the consumer choice model to accomplish the estimation our results indicate that demand rates estimated naively by using observed sales rates are biased even for items that have very few occurrences of stock outs we also find significant differences among the substitution rates of the six brands the methods proposed in our paper can be modified to apply to many nonvending retail settings in which consumer choices are observed not their preferences and choices are constrained because of unavailability of items in the choice set one such context is in store grocery retailing where similar issues of information availability arise in this context an important issue that would need to be dealt with is changes in the retail environment caused by retail promotions

quality and competition in recent years the practitioner literature in operations management has seen a dramatic surge in articles on quality management it reflects the increased emphasis on quality by u s firms which has been attributed largely to increased competition faced by them the question of how quality is influenced by competitive intensity however has not received much attention either in the practitioner or the academic research literatures the notion of competitive intensity itself has not been defined precisely in this paper we develop formal models of oligopolistic competition to investigate whether equilibrium levels of quality increase as competition intensifies we consider three different competitive settings i asymmetric duopolistic competition where the dominant firm s intrinsic demand potential decreases ii a symmetric duopoly where the firms are precluded from cooperating in setting quality levels and iii symmetric oligopolistic competition where the number of firms increases we find that the relation between equilibrium quality and competitive intensity depends on what is understood by increased competition and in addition the relation is contingent on the values of parameters describing the cost and demand structure for the industry

single period multiproduct inventory models with substitution we study a single period multiproduct inventory problem with substitution and proportional costs and revenues we consider n products and n demand classes with full downward substitution i e excess demand for class i can be satisfied using product j for i j we first discuss a two stage profit maximization formulation for the multiproduct substitution problem we show that a greedy allocation policy is optimal we use this to write the expected profits and its first partials explicitly this in turn enables us to prove additional properties of the profit function and several interesting properties of the optimal solution in a limited computational study using two products we illustrate the benefits of solving for the optimal quantities when substitution is considered at the ordering stage over similar computations without considering substitution while ordering specifically we show that the benefits are higher with high demand variability low substitution cost low profit margins or low price to cost ratio high salvage values and similarity of products in terms of prices and costs

multinomial logit market share models equilibrium characteristics and strategic implications we specify and analyze the conditions under which the mnl market share models are appropriate for equilibrium analysis our results show that a linear price response function as is often used in empirical research in conjunction with the typical concavity assumed in a large range of marketing response functions would yield an interior equilibrium solution we then consider the optimal reactions on pricing and marketing spending to entry and potential market expansion in the context of the mnl models we demonstrate that the entry of a new brand evokes a decrease in the equilibrium prices of the existing brands as a defensive reaction this is true in both an expanding market as well as a fixed market however while new entry into a fixed market would trigger the incumbents to lower the marketing expenditure we show that firms tend to raise marketing activities as they experience market expansion consequently there exist distinct possibilities that marketing efforts for the existing brands increase in view of entry in an expanding market further managerial and marketing implications for endogeneity of the number of firms are explored

the role of corporate sustainability performance for economic performance a firm level analysis of moderation effects abstract this paper analyses the link between sustainability management and economic performance its main research question concerns the association of social responsibility and environmental management with economic performance determinants of the latter and possible moderation effects based on data collected from financial databases and kinder lydenberg domini for the period 1992 to 2003 the paper analyses the link of corporate sustainability performance with economic performance using panel estimation techniques the analysis shows that advertising intensity moderates the association of corporate sustainability performance and economic performance as measured by tobin s q for research and development efforts relative to firm size no moderating role on the link between corporate sustainability and economic performance is identified a sensitivity analysis using separate measures for social and environmental performance reveals that the latter only has a direct effect and the former only a fully moderated effect on economic performance policy and management implications of these findings are discussed

do stock investors value corporate sustainability evidence from an event study this paper analyzes the impacts of index inclusions and exclusions on corporate sustainable firms by studying a sample of us stocks that are added to or deleted from the dow jones sustainability world index over the period 2002 2008 the impacts are measured in terms of stock return risk and liquidity we cannot find any strong evidence that announcement per se has any significant impact on stock return and risk however on the day of change index inclusion exclusion stocks experience a significant but temporary increase decrease in stock return liquidity deteriorates after the announcement day and bounces back significantly near the day of change systematic risk shows little change after announce ments but idiosyncratic risk is higher after announcements the overall results support harris and eitan s the journal of finance41 4 815 829 1986 price pressure hypothesis which posits that event announcement does not carry information and any shift in demand and hence the corresponding price change and liquidity change is temporary

implications of agricultural trade liberalization for the developing countries abstract the developing countries as a group could expect to experience only small welfare gains if they chose not to actively participate in agricultural trade liberalization and relied solely on the benefits of partial liberalization in the oecd countries participation along the lines of the dunkel package with the developing countries reducing positive assistance by less than the developed countries would yield gains of the order of us 20 billion more comprehensive participation in trade liberalization involving reductions of both positive and negative protection would almost triple these welfare gains while some developing countries do not gain from trade liberalization even with full participation the number of such countries and the magnitude of their losses are greatly reduced

profit efficiency among basmati rice producers in pakistan punjab farm specific profit inefficiency among basmati rice producers was estimated from a variable coefficient profit frontier the mean level of inefficiency at farm resources and price levels was 28 with a wide range 5 87 average loss of profit was rs 1 222 per hectare socioeconomic factors related to profit loss were the farm household s education nonagricultural employment and a credit constraint institutional determinants of profit loss were a water constraint and the late application of fertilizer punjab wide benefits of increasing farmer s profit efficiency are large a 25 reduction in profit loss among basmati rice producers may generate over rs 240 million in extra profits each rice season rice is a major export commodity for pakistan generating about 2 5 billion pakistan rupees rs annually or 20 of foreign exchange earnings from commodity trade in the early 1980s two varieties dominate in pakistan s international trade in rice basmati 370 a high quality long grained aromatic variety and the medium long grained irri 6 distinct export markets exist for these rices over 90 of the basmati is exported to oil rich middle eastern nations while the mediumlong varieties are mainly marketed in southeast asia in 1983 the export price of basmati was about rs 7 900 per ton while the price of medium long grained varieties averaged rs 2 700 per ton pakistan has a comparative advantage in the international market for basmati but probably not for medium long grained rices azhar and mamhud historically pakistan had a near monopoly in international trade in basmati but now faces increased competition from thailand and the united states efferson therefore pakistan must strive to increase the efficiency of basmati production to retain its comparative advantage and competitive edge in foreign rice markets basmati 370 is a pure line selection made in

long run competition in capacity short run competition in price and the cournot model in this article we investigate the nature of equilibrium in markets in which firms choose the scale of operation before they make pricing decisions we analyze a duopoly model in which firms choose their capacities before engaging in bertrand like price competition we demonstrate that the cournot outcome is unlikely to emerge in such markets and that the equilibrium tends to be more competitive than the cournot model would predict in addition our results indicate a tendency toward asymmetric firm sizes and price dispersion that results from the mixed strategies firms use in equilibrium

the returns from schooling in a diversified rural economy controlling for the endogeneity of activity choice and considering both household head and family schooling we findevid ence of high returns from schooling in both crop andnoncrop activities as schooling levels increase the returns from schooling shift away from crop production failure to control for activity selection andfamily schooling is likely to result in biasedestimates of the returns from schooling in individual activities copyright 2000 oxford university press

health and schooling investments in africa this paper first outlines an organizing framework for considering how health and schooling affect labor productivity and growth and how household and community factors can in turn affect the demand for these human capital investments both cross country growth models and various aspects of microeconomic studies of individual productivity as related to education and health are discussed the conclusion offers some tentative leads for policy in this area based on existing research and an agenda for future research

the competitive newsboy we consider a competitive version of the classical newsboy problem in which a firm must choose an inventory or production level for a perishable good with random demand and the optimal solution is a fractile of the demand distribution and investigate the impact of competition upon industry inventory a splitting rule specifies how initial industry demand is allocated among competing firms and how any excess demand is allocated among firms with remaining inventory we examine the relation between equilibrium inventory levels and the splitting rule and provide conditions under which there is a unique equilibrium our most general result is that if all excess demand is reallocated i e there is perfect substitutability then competition never leads to a decrease in industry inventory

product and price competition with satiation effects consumers become satiated with a product when purchasing too much too quickly how much is too much and how quickly is too quickly depends on the characteristics of the product relative to the time interval between consumption periods knowing that consumers allocate their budget to products that generate less satiation effects retailers should then choose to sell products that induce minimal satiation but usually this is operationally more costly to study this trade off we provide an analytical model based on utility theory that relates customer consumption to price and satiation in the context of multiple competing retailers we determine the purchasing pattern over time and provide an explicit expression to determine the consumption level in steady state we derive market shares and show that they take the form of an attraction model in which the attractiveness depends on price and product satiation we use this to analyze the competition between firms that maximize long term average profit we characterize the equilibrium under three scenarios i price only competition ii product only competition and iii price and product competition the results reveal the interplay between a key marketing lever price and the firm s ability to offer products that generate less satiation in particular we show that when a firm becomes more efficient at reducing satiation its competitor may benefit if competition is on product only but not if it is on price and product we also find that when satiation effects are not managed a firm s profit may be significantly reduced while a strategic competitor can largely benefit this paper was accepted by yossi aviv operations management

joint inventory and pricing decisions for an assortment we seek optimal inventory levels and prices of multiple products in a given assortment in a newsvendor model single period stochastic demand under price based substitution but not stockout based substitution we address a demand model involving multiplicative uncertainty motivated by market share models often used in marketing the pricing problem that arises is known not to be well behaved in the sense that in its deterministic version the objective function is not jointly quasi concave in prices however we find that the objective function is still reasonably well behaved in the sense that there is a unique solution to the first order conditions and this solution is optimal for our problem

the impact of education in rural ghana examining household labor allocation and returns on and off the farm most of the human capital literature pertaining to developing countries focuses on the returns to education in either farm work or wage work few studies examine how education affects the allocation of time between these activities this paper estimates the returns to education in farm and off farm work and consequently the role of education in determining the allocation of labor the results from this study show that off farm work has a much higher return to education than does farm work and suggest that this divergence in returns affects the allocation of labor in farm households between farm and off farm work

prices and productivity in agriculture developing countries often tax agriculture heavily a practice that might affect the productivity as well as the quantity of resources allocated to agriculture a variable coefficient cross country agricultural production function is estimated with past price expectations among the determinants of the production coefficients productivity s responsiveness to those expectations implies that had these developing economies eliminated price interventions agricultural productivity would have increased on average by about a fourth copyright 1993 by mit press

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

looking at pro poor growth from an agricultural perspective summary pro poor growth has been identified as one of the most promising pathways to accelerate poverty reduction in developing countries the diagnostic pro poor growth toolbox has so far focused on the income dimension as well as key non income achievements in education and health this article contributes to the literature by expanding the toolbox with several new measures that take into account the extraordinary importance of agricultural productivity for poverty reduction in developing countries we distinguish between land productivity and labor productivity and find that the poor identified by low incomes poor education outcomes low land productivity and low labor productivity overlap only to a small degree suggesting that analyses of pro poor growth from these different perspectives are complementary the toolbox is then applied to three comparable household surveys from rwanda eicv data for the years 1999 2001 2005 06 and 2010 11 a country that has experienced impressive economic growth since the genocide in the mid 1990s and that has undertaken considerable efforts to increase agricultural productivity and improve the population s access to social services over the first decade of the 2000s our application shows that the enormous progress made in the income education and health dimension of well being has been pro poor according to most definitions of the concept the new tools reveal that the land productivity poor experienced pro poor growth in the relative and absolute sense while the labor productivity poor increased their labor productivity relatively but not absolutely faster than the labor productivity rich even though the former dispose of considerably lower education levels

two period dynamic versus fixed ratio pricing in a capacity constrained duopoly this paper analyzes the impact of dynamic and fixed ratio pricing policies on firm profits and equilibrium prices under competition firms that have equal inventories of perfectly substitutable and perishable products compete for customer segments that demand the product at different times in each period customers first purchase from the low price firm and then from the high price firm up to their inventories provided the prices are lower than the maximum they are willing to pay the main conclusions of this paper are as follows although dynamic pricing is a more sophisticated policy than fixed ratio pricing it may lead to decreased equilibrium profits under both pricing policies one firm assumes the role of a low cost high output firm while the other assumes the role of a high cost low output firm and the supply demand ratio has more impact on the outcome of the competition than the heterogeneity in consumer reservation prices

an investigation of real versus perceived csp in s p 500 firms firms are spending billions annually in the name of corporate social responsibility csr whilst markets are increasingly willing to reward good and responsible firms they lack the instruments to measure corporate social performance csp to convince investors and other stakeholders firms invest heavily in building a reputation for good corporate behaviour this article argues that reputations for csp are often unrepresentative of true csp and investigates how differences in perceived and actual as measured by the fortune and kld databases respectively can partly be explained by firm characteristics amongst other things it finds that overrated firms are more likely to be relatively big profitable operating in non polluting but competitive industries and with no history of wrong doings to their primary stakeholders they will also typically spend a lot of effort satisfying the claims of their secondary stakeholders above all the results emphasise the need for researchers to recognise that the databases measure different phenomenon and are not interchangeable

the role of education on the adoption of chemical fertiliser under different socioeconomic environments in ethiopia studies on input adoption consider education as one of the most important factors that affect adoption decisions however very little is known about the spill over effect of intra household education on the adoption process and about the impact of education on adoption decisions under different socioeconomic conditions we investigate these two issues using a discrete choice model the results indicate that the decision making process is a decentralised one in which educated adult members of the household actively participate in the decision making process this casts doubt on the traditional assumption that the household head is the sole decision maker the results reveal that there is a substantial and statistically significant intra household spill over effect of education on the adoption decision of households the results of the study also show that the coefficient of the education and the environment interaction variable is negative and statistically significant this demonstrates that education and socioeconomic environments could be substitutes in modern environments and complementary in traditional ones this implies that the expansion of education in traditional areas may be more attractive than in modern areas since education is usually the only means to enhance the ability of farmers to acquire synthesise and respond to innovations such as chemical fertiliser

a static approximation for dynamic demand substitution with applications in a competitive market we propose a static approximation of dynamic demand substitution behavior based on a fluid network model and a service inventory mapping this approximation greatly enhances our ability to analyze the interdependent inventory service price and product assortment decisions in noncompetitive and competitive scenarios with demand substitution we demonstrate that the approximation is well behaved and then apply it to two previously intractable applications first we study a price and service competition between single product retailers after establishing a unique pure strategy nash equilibrium we find that competition results in lower price higher demand and a higher level of inventory we also observe that the aggregate profit and inventory level increase to positive constants as the number of retailers goes to infinity second we study a duopolistic competition on price service and product assortment we establish a pure strategy nash equilibrium for the product assortment competition and identify a condition for uniqueness we find that competition on both price and product assortment results in lower price and less variety for each competitor but the total number of products and the aggregate inventory level in a duopoly market are both likely to be higher than in a monopolistic market

product assortment in a triopolgy producers of super premium ice cream such as haagen dazs offer a smaller assortment of flavors than the producers of lesser quality ice cream examples of this phenomenon can be found in other industries as well in many industries the producers of higher quality products offer a smaller assortment of flavors colors sizes patterns textures fragrances tones styles models designs types or other options this paper explores when and why producers of super premium products should find it profitable to offer a smaller assortment than the producers of nonpremium products we derive a nash equilibrium both on prices and product assortments for a triopoly at the nash equilibrium we show that additional product quality increased consumer price sensitivity and greater assortment costs discourages product assortment we also show that a larger market potential greater competitive costs and sharper competition encourage more assortment by the super premium producer

climate change health care access and regional influence on components of u s agricultural productivity this article examines factors driving three components of total factor productivity change tfpc in u s agriculture technical change tc technical efficiency change tec and scale and mix e

externality effects of education dynamics of the adoption and diffusion of an innovation in rural ethiopia abstract this article investigates the role of schooling at the household and community levels in the adoption and diffusion of agricultural innovations in rural ethiopia we find that household level education is important to the timing of adoption but less crucial to the question of whether a household has ever adopted fertilizer since those without schooling may eventually copy the educated community level education substitutes for low levels of household education encouraging uneducated farmers to adopt sooner than would be predicted in the absence of educated neighbors moreover community level education is complementary to household education in determining which farmers will eventually adopt thus evidence is presented to suggest that there are two externality effects educated farmers are early innovators providing an example that may be copied by less educated farmers and educated farmers are better able to copy those who innovate first enhancing diffusion of the new technology more wide

on the determinants of corporate social responsibility international evidence on the financial industry this article sets out to undertake a thorough point by point examination of the theory postulated by campbell 2007 in which an attempt is made to specify the conditions under which corporations may or may not act in socially responsible ways in order to ensure the overall reliability of our study and to attempt to provide a new understanding of and greater insights into whether corporate social responsibility csr is affected by financial and institutional variables we empirically investigate a total of 520 financial firms in 34 countries between the years 2003 and 2005 our empirical findings are i firms with larger size are more csr minded and the financial performance and csr are not related ii firms would actually act in more socially responsible ways to enhance their competitive advantages when the market competitiveness is more intense iii financial firms in countries with stronger levels of legal enforcement tend to engage in more csr activities however interestingly and rather strikingly those firms in countries with stronger shareholder rights tend to engage in less csr activities and iv self regulation within the financial industry has a significantly positive effect on csr with firms being found to act in more socially responsible ways in those countries which have more cooperative employer employee relations higher quality management schools and a better macroeconomic environment

farm productivity and efficiency in rural bangladesh the role of education revisited this article reassesses the debate over the role of education in farm production in bangladesh using a large dataset on rice producing households from 141 villages average and stochastic production frontier functions are estimated to ascertain the effect of education on productivity and efficiency a full set of proxies for farm education stock variables are incorporated to investigate the internal as well as external returns to education the external effect is investigated in the context of rural neighbourhoods our analysis reveals that in addition to raising rice productivity and boosting potential output household education significantly reduces production inefficiencies however we are unable to find any evidence of the externality benefit of schooling neighbour s education does not matter in farm production we discuss the implication of these findings for rural education programmes in bangladesh

learning by doing and learning from others human capital and technical change in agriculture household level panel data from a nationally representative sample of rural indian households describing the adoption and profitability of high yielding seed varieties hyvs associated with the green revolution are used to test the implications of a model incorporating learning by doing and learning spillovers the estimates indicate that i imperfect knowledge about the management of the new seeds was a significant barrier to adoption ii this barrier diminished as farmer experience with the new technologies increased iii own experience and neighbors experience with hyvs significantly increased hyv profitability and iv farmers do not fully incorporate the village returns to learning in making adoption decisions

optimal and competitive assortments with endogenous pricing under hierarchical consumer choice models this paper studies assortment planning and pricing for a product category with heterogeneous product types from two brands we model consumer choice using the nested multinomial logit framework with two different hierarchical structures a brand primary model in which consumers choose a brand first then a product type in the chosen brand and a type primary model in which consumers choose a product type first then a brand within that product type we consider a centralized regime that finds the optimal solution for the whole category and a decentralized regime that finds a competitive equilibrium between two brands we find that optimal and competitive assortments and prices have quite distinctive properties across different models specifically with the brand primary model both the optimal and the competitive assortments for each brand consist of the most popular product types from the brand with the type primary choice model the optimal and the competitive assortments for each brand may not always consist of the most popular product types of the brand instead the overall assortment in the category consists of a set of most popular product types the price of a product under the centralized regime can be characterized by a sum of a markup that is constant across all products and brands its procurement cost and its marginal operational cost implying a lower price for more popular products the markup may be different for each brand and product type under the decentralized regime implying a higher price for brands with a larger market share these properties of the assortments and prices can be used as effective guidelines for managers to identify and price the best assortments and to rule out nonoptimal assortments our results suggest that to offer the right set of products and prices category and or brand managers should create an assortment planning process that is aligned with the hierarchical choice process consumers commonly follow to make purchasing decisions this paper was accepted by pradeep chintagunta and preyas desai special issue editors this paper was accepted by pradeep chintagunta and preyas desai special issue editors

category management and coordination in retail assortment planning in the presence of basket shopping consumers this paper studies the assortment planning problem with multiple merchandise categories and basket shopping consumers i e consumers who desire to purchase from multiple categories we present a duopoly model in which retailers choose prices and variety level in each category and consumers make their store choice between retail stores and a no purchase alternative based on their utilities from each category the common practice of category management cm is an example of a decentralized regime for controlling assortment because each category manager is responsible for maximizing his or her assigned category s profit alternatively a retailer can make category decisions across the store with a centralized regime we show that cm never finds the optimal solution and provides both less variety and higher prices than optimal in a numerical study we demonstrate that profit loss due to cm can be significant finally we propose a decentralized regime that uses basket profits a new metric rather than accounting profits basket profits are easily evaluated using point of sale data and the proposed method produces near optimal solutions

the paradigm of agricultural efficiency and its implication on food security in africa what does meta analysis reveal summary the study investigates whether african agricultural efficiency levels have been improving or not and what drives them over the years based on 442 frontier studies using meta regression analysis the results show that the mean efficiency estimates from studies decrease significantly as year of survey in the primary study increases also studies published in journals with parametric specification and with panel data produced significantly higher efficiency estimates while those with a focus on grain crops reported significantly lower efficiency estimates other results show that education followed by experience extension and credit are the major drivers of agricultural efficiency levels in africa

signaling sustainability leadership empirical evidence of the value of djsi membership we explore the relationship between corporate sustainability reputation and firm value by asking whether signaling sustainability leadership through membership on a recognized sustainability index is value generating increasingly stakeholders are demanding that firms demonstrate their commitment to sustainability one signal that companies can send to stakeholders to indicate that they are sustainability leaders is membership on a recognized best in class sustainability index this article explores both the short term and the intermediary impact on north american firms of being included or removed from the dow jones sustainability world index djsi our results provide evidence that being added to the djsi results in a sustained increase in a firm s share price suggesting that the benefits of being included on the djsi outweigh the costs associated with applying this article also notes a temporary decrease in the value of firms for the first 10 days after their removal from the djsi however this effect is eliminated within the next ten trading days

an efficient algorithm for capacitated assortment planning with stochastic demand and substitution abstract the ever increasing product variety in grocery retailing is in conflict with the limited shelf space managing the assortment and regular order quantity for perishable and non perishable products is therefore a core task for retailers retailers want to maximize profit by considering potential revenues purchase costs diminishing profits for products and opportunity costs for unfulfilled demand when determining assortment sizes and order volume to meet stochastic consumer demand we considered a newsvendor based decision model that jointly optimizes assortment size and the associated order volumes for listed items the model considers out of assortment ooa and out of stock oos substitution effects the model is a structural equivalent to the model described in kok and fisher 2007 and solved there via a heuristic procedure we develop an optimal solution procedure and a time efficient heuristic that solves the model the heuristic suggested is applicable for practically relevant large scale problem instances numerical tests reveal that the heuristic procedure produces close to optimal solutions and outperforms the kok and fisher heuristic with regard to both computational time and solution quality a simulation study with discrete demand justifies our approach with using continuous demand distributions the numerical analyses show that considering substitution effects in a decision based model has a significant impact on the total profit and solution structure further managerial insights are presented with regard to assortment heterogeneity when shelf size substitution and demand variability are varied

education and technical efficiency during the green revolution in pakistan tion is more likely to arise during disequilibrium caused by technical change in agriculture this may be because technical change renders the existing cultural practices obsolete or inadequate and calls for an adjustment a more educated farmer is supposed to make the required adjustment more quickly this article tests the foregoing hypothesis in pakistan agriculture during the green revolution when introduction of new crop varieties disturbed the prevailing equilibrium for this purpose a production function approach is used and the analysis is conducted not only for the new crop varieties but also for their traditional counterparts the results lend support to the hypothesis by showing that the worker effect is stronger for new crop varieties than it is for traditional ones the article is divided into five sections in the next section a brief review of the literature is presented section iii presents the hypothesis and discusses the methodology used for the analysis the results and their policy implications are discussed in section iv and section v concludes the article ii brief literature review in a pioneering study exploring the economic effects of education z griliches used production function analysis to highlight the contri

stocking retail assortments under dynamic consumer substitution we analyze a single period stochastic inventory model newsboy like model in which a sequence of heterogeneous customers dynamically substitute among product variants within a retail assortment when inventory is depleted the customer choice decisions are based on a natural and classical utility maximization criterion faced with such substitution behavior the retailer must choose initial inventory levels for the assortment to maximize expected profits using a sample path analysis we analyze structural properties of the expected profit function we show that under very general assumptions on the demand process total sales of each product are concave in their own inventory levels and possess the so calleddecreasing differences property meaning that the marginal value of an additional unit of the given product is decreasing in the inventory levels of all other products for a continuous relaxation of the problem we then show via counterexamples that the expected profit function is in general not even quasiconcave thus global optimization may be difficult however we propose and analyze a stochastic gradient algorithm for the problem and prove that it converges to a stationary point of the expected profit function under mild conditions finally we apply the algorithm to a set of numerical examples and compare the resulting inventory decisions to those of some simpler naive heuristics the examples show that substitution effects can have a significant impact on an assortment s gross profits the examples also illustrate some systematic distortions in inventory decisions if substitution effects are ignored in particular under substitution one should stock relatively more of popular variants and relatively less of unpopular variants than a traditional newsboy analysis indicates

the multi item newsvendor model with cross selling and the solution when demand is jointly normally distributed abstract products are often demanded in tandem because of the cross selling effect the demand for an item can increase if sales of its cross selling associated items are achieved or decrease when the associated items are out of stock resulting in lost sales therefore a joint inventory policy should be pursued in a cross selling system this paper introduces customer driven cross selling into centralized and competitive newsvendor nv models by representing an item s effective demand as a function of other items order quantities we derive first order optimality conditions for the centralized model in addition to pure strategy nash equilibrium conditions and uniqueness conditions of the equilibria for the competitive model we further develop gradient based gb and iteration based ib algorithms to solve the centralized and competitive models respectively a computational study verifies the effectiveness of the proposed algorithms the computational results show that a larger cross selling effect leads to a larger order quantity in a centralized nv model but a smaller order quantity in a competitive nv model and a larger positive correlation between items demands leads to higher profits with smaller order quantities in both models moreover nvs will order more items if the demand variance is greater however resulting in lower profits in a competitive situation one will prefer smaller order quantities than in a centralized decision situation

inventory management under price based and stockout based substitution abstract we examine a stochastic inventory and pricing problem for a firm that sells two vertically differentiated products the demands for the two products are determined by total random market size and the customers net utility from buying the two products which is determined by the products quality attributes the individual quality valuation unknown to the firm and the selling prices in case the preferred product is out of stock customers may be willing to buy a substitute instead if their net utility is non negative therefore we analyze an inventory and pricing model considering price based and stockout based substitution we show that the demand function is not continuous in price by decomposing the profit function into different price regimes we are able to derive closed form expressions for the stockout based substitution rates upward and downward substitution and the optimal inventory levels under exogenous pricing under endogenous pricing we find that the profit function is not necessarily unimodal however we show that a unique solution exists for the integrated price and inventory problem under price based substitution only numerical results reveal that not considering stockout based substitution i leads to lower profit margins for high quality products and ii may cause severe supply demand mismatches throughout the entire assortment finally we show the performance of two approximated pricing policies

where has all the education gone cross national data show no association between increases in human capital attributable to the rising educational attainment of the labor force and the rate of growth of output per worker this implies that the association of educational capital growth with conventional measures of total factor production is large strongly statistically significant and negative these are on average results derived from imposing a constant coefficient however the development impact of education varied widely across countries and has fallen short of expectations for three possible reasons first the institutional governance environment could have been sufficiently perverse that the accumulation of educational capital lowered economic growth second marginal returns to education could have fallen rapidly as the supply of educated labor expanded while demand remained stagnant third educational quality could have been so low that years of schooling created no human capital the extent and mix of these three phenomena vary from country to country in explaining the actual economic impact of education or the lack thereof

international productivity patterns accounting for input quality infrastructure and research in this paper we present measures of land and labor productivity for a group of ninety eight developed and developing countries using an entirely new data set with annual observations spanning the past three decades the substantial cross country and intertemporal variation in productivity in our sample is linked to both natural and economic factors we extend previous work by dealing with multiple sources of systematic measurement error in conventional agricultural inputs the mix of conventional inputs indicators of quality of agricultural inputs and the amount of publicly provided infrastructure are all significant in explaining observed cross sectional differences in productivity patterns

a classification of the literature on the planning of substitutable products abstract a company s assortment of products and corresponding inventory levels are constrained by available resources such as production capacity storage space and capital to acquire the inventory thus customers may not always be able to find a most preferred product at the time of purchase this unsatisfied demand is often substituted with an alternative in the extant literature there have been an increasing number of studies that consider product substitution when planning product assortment inventory and capacity in conjunction with pricing in this paper we classify the literature on the planning of substitutable products published in the major om and marketing journals during the past thirty years 1974 2013 and present a comprehensive taxonomy of the literature one criterion is adopted to discuss modeling objectives and three major criteria are provided to define the nature of product substitution including substitution mechanism substitution decision maker and direction of substitutability we also identify research gaps to provide guidance for related research in the future

the manufacturing sector s environmental motives a game theoretic analysis what motivates manufacturing companies to make costly investments in producing in an environmentally clean manner the traditional argument is that such behaviour is value reducing and that therefore firms must be forced by regulation to invest in green production processes a counter argument is that firms have an incentive to make environmental investments in an attempt to attract green consumers and investors hence gaining competitive advantage over their rivals in this paper we employ a game theoretic approach that demonstrates that competing firms incentives to make voluntary investments in environmental clean up are affected by the size of the investment costs and the extent of consumer and investor green awareness we argue that an increase in green behaviour can be induced by a combination of governmental subsidies for firms that invest in environmentally clean production processes together with an education program that promotes green awareness amongst consumers investors and the managers themselves

education and innovation adoption in agriculture evidence from hybrid rice in china this paper uses the diffusion of f1 hybrid rice as a case for examining the effects of education on the adoption of new technology in china a simple behavioral model that treats the adoption of hybrid rice as a portfolio selection problem is presented the implications of the model are tested with farm level data collected from a sample of 500 households in hunan province the results from a dichotomous probit model and a two limit tobit model are consistent with the hypothesis that education has a positive impact on the adoption of new technology

total factor productivity growth in agriculture a malmquist index analysis of 93 countries 1980 2000 in this paper we examine levels and trends in agricultural output and productivity in 93 developed and developing countries that account for a major portion of the world population and agricultural output we make use of data drawn from the food and agriculture organization of the united nations and our study covers the period 1980 2000 due to the non availability of reliable input price data the study uses data envelopment analysis dea to derive malmquist productivity indexes the study examines trends in agricultural productivity over the period issues of catch up and convergence or in some cases possible divergence in productivity in agriculture are examined within a global framework the paper also derives the shadow prices and value shares that are implicit in the dea based malmquist productivity indices and examines the plausibility of their levels and trends over the study period

global standards and ethical stock indexes the case of the dow jones sustainability stoxx index the increased scrutiny of investors regarding the non financial aspects of corporate performance has placed portfolio managers in the position of having to weigh the benefits of holding the market against the cost of having positions in companies that are subsequently found to have questionable business practices the availability of stock indexes based on sustainability screening makes increasingly viable for institutional investors the transition to a portfolio based on a socially responsible investment sri benchmark at relatively low cost the increasing share of socially responsible investments may play a role in providing incentives towards a continuous upgrading of sustainability standards to the extent that their performance is not systematically inferior to that of the other funds this article examines whether these incentives have been so far detectable with particular reference to the dow jones sustainability stoxx index djssi that focuses on the european corporations with the highest csr scores among those included in the dow jones stoxx 600 index the aim of the article is twofold first we analyse the performance of the djssi over the period 2001 2006 compared to that of the surrogate complementary index sci a new benchmark that includes only the components of the dj stoxx 600 that do not belong to the ethical index to evaluate more correctly the size of possible divergent performances second we perform an event study on the same data set to analyse whether the stock market evaluation reacts to the inclusion deletion in the djssi in both cases the results suggest that the evaluation of the csr performance of a firm is a significant criterion for asset allocation activities

the economics of product variety a survey demand for variety may arise from a taste for diversity in individual consumption and or from diversity in tastes even when each consumer chooses a single variant the full degree of variety potentially demanded will not in general be supplied because scale economies even to a small degree mean that the potential welfare or revenue gain from greater variety must be balanced against the lower unit production costs with fewer variants the economics of product variety consists essentially in analysing the effect of this balance in different situations and comparing the degree of product variety for different market structures with each other and with the optimum the survey commences with the work on market structures with single product firms generalized monopolistic competition tracing modern developments in both the chamberlinian and hotelling traditions the latter has been particularly fruitful due to the expansion of the original locational ideas into virtual spaces in product characteristics the emphasis in recent work on product variety has been on multiproduct firms in both monopolistic and oligopolistic structures including strategic market preemption although most work has been in a full information context there have been advances in product variety under imperfect information either by consumers to properties of the firms products or firms as to consumers demands

the meta production function approach to technological change in world agriculture abstract an alternative meta production function for agriculture is estimated with the cross section data for 43 countries and three years 1960 1970 and 1980 constructed and used by kawagoe hayami and ruttan and hayami and ruttan in their studies by allowing for country specific efficiency factors and using a flexible functional form the transcendental logarithmic production function strikingly different results from those of kawagoe hayami and ruttan are obtained in particular it is found that elasticity of output with respect to machinery is variable and the degree of local returns to scale is not constant and increases with the usage of machinery

the causal effect of education on farm related disability evidence from a compulsory schooling reform in taiwan we investigate the causal effect of education on the incidence and severity of farm related disability our dataset is comprised of 75 708 farmers drawn from the taiwanese agriculture census supplemented with administrative data on farmer disability approximately 46 of the farmers in our sample were affected by legislation expanding compulsory schooling from the primary school level to the junior high school level utilizing the compulsory schooling reform as a natural experiment for identification we estimated an instrumental variable two part model of the incidence and severity of disability where the latter is measured using the number of disabled days for farmers aged from 35 to 45 we find that greater educational attainment significantly reduced the likelihood of farm related disability as well as the severity of disability two potential mechanisms for this effect were fewer on farm work days and less use of chemical inputs to farm production among more educated farmers

what determines the inclusion in a sustainability stock index a panel data analysis for european companies this paper examines the determinants of the inclusion of european companies in the dow jones sustainability world index and the dow jones stoxx sustainability index in doing so the paper contributes to the micro econometric literature analyzing the determinants and economic effects of sustainability performance in three respects first it examines a broad measure of corporate sustainability behavior and thus does not only apply narrow measures of environmental performance such as toxic releases which is common in other studies second the paper examines the effect of internal assessment processes regarding corporate sustainability performance by an independent financial service institution finally it analyzes the influence of unobserved heterogeneity in the framework of panel data models the analysis shows that the probability for an inclusion in the sustainability indexes strongly decreases if a company does not respond to the written survey of the assessing institution furthermore time invariant random effects and an autoregressive structure in the stochastic components are important factors in contrast a significant influence of past economic performance cannot be confirmed robustly

a general equilibrium model for industries with price and service competition this paper develops a stochastic general equilibrium inventory model for an oligopoly in which all inventory constraint parameters are endogenously determined we propose several systems of demand processes whose distributions are functions of all retailers prices and all retailers service levels we proceed with the investigation of the equilibrium behavior of infinite horizon models for industries facing this type of generalized competition under demand uncertainty we systematically consider the following three competition scenarios 1 price competition only here we assume that the firms service levels are exogenously chosen but characterize how the price and inventory strategy equilibrium vary with the chosen service levels 2 simultaneous price and service level competition here each of the firms simultaneously chooses a service level and a combined price and inventory strategy 3 two stage competition the firms make their competitive choices sequentially in a first stage all firms simultaneously choose a service level in a second stage the firms simultaneously choose a combined pricing and inventory strategy with full knowledge of the service levels selected by all competitors we show that in all of the above settings a nash equilibrium of infinite horizon stationary strategies exists and that it is of a simple structure provided a nash equilibrium exists in a so called reduced game we pay particular attention to the question of whether a firm can choose its service level on the basis of its own input characteristics i e its cost parameters and demand function only we also investigate under which of the demand models a firm under simultaneous competition responds to a change in the exogenously specified characteristics of the various competitors by either i adjusting its service level and price in the same direction thereby compensating for price increases decreases by offering improved inferior service or ii adjusting them in opposite directions thereby simultaneously offering better or worse prices and service

a critical review of sustainable business indices and their impact most studies into the performance of socially responsible investment vehicles have focused on the performance of sustainable or socially responsible mutual funds this research has been complemented recently by a number of studies that have examined the performance of sustainable investment indices in both cases the majority of studies have concluded that the returns of socially responsible investment vehicles have either underperformed or failed to outperform comparable market indices although the impact of sustainable indices to date has been limited the recent launch of sustainable indices by dow jones and ftse suggests that more attention is being paid to the subject by financial markets investors and companies this development raises a number of important issues which are reviewed in this article a the performance of indices compared with their benchmark indices b the methodologies employed in compiling the indices and c the impact of the indices on companies and the investment community the article concludes with a number of suggestions for areas that merit future research

optimal production pricing and substitution policies in continuous review production inventory systems abstract we consider the optimal production pricing and substitution policies of a continuous review production inventory system with two products a high end product and a low end product each product has its associated customer stream however the demands for the low end product may be satisfied by the high end product we formulate the problem as a markov decision process and characterize the structure of the optimal control policy which specifies when to produce for each product when to use the high end product as a substitute and how to set the optimal prices we show that a base stock production policy is optimal however the optimal base stock level for each product depends on the inventory level of the other product and it features a monotonic property we also demonstrate that the optimal substitution policy is a rationing policy with the rationing level depending on the total inventory amount we find that the optimal prices can be either decreasing or increasing in the inventory levels depending on the forms of demand functions furthermore we utilize numerical experiments to investigate the impact of different system characteristics on the benefits of using substitution and dynamic pricing finally we investigate when the dynamic pricing strategy and the substitution strategy are complements or substitutes

sources of agricultural productivity growth and stagnation in sub saharan africa this paper examines sources of agricultural growth in sub saharan africa growth in the stock of traditional inputs land labor livestock remains the dominant source of output growth growth in modern input use was of secondary importance but still accounted for a 0 2 0 4 annual growth rate in three of four sub regions econometric results support earlier studies that suggest that land abundance may be a constraint on land productivity growth growth in agricultural exports and historic calorie availability had positive impacts on productivity these latter results suggest that positive feedback effects exist between export performance and food security on one hand and agricultural productivity on the other

the intercountry agricultural production function and productivity differences among countries abstract the sources of differences in labor productivity in agriculture between developed countries dc s and less developed countries ldc s are identified by estimating an aggregate agricultural production function based on cross county data for 1960 1970 and 1980 the production function was found to be stable over the entire period agriculture in the dc s was characterized by increasing returns and in the ldc s by constant returns to scale the results imply that unfavorable man land ratios do not represent an immediate barrier to rapid agricultural development in the low income ldc s but they may create a serious agricultural adjustment problem as those countries advance into the middle income range

land distribution and international agricultural productivity the unequal distribution of agricultural land is often cited as a source of inefficiency in agriculture previous cross country studies of agricultural productivity differences though have not considered land inequality this article addresses this issue by using cross country data on inequality in operational holdings of agricultural land from deininger and squire 1998 in an estimation of an agricultural production function the gini coefficient for land holdings is found to have a significant negative relationship with productivity this is consistent with the existence of heterogeneity in productivity by farm size within countries a one standard deviation drop in the gini coefficient implies an increase in productivity of 8 5

is there a slowdown in agricultural productivity growth in south america this article estimates agricultural productivity growth in 10 south american countries in 1969 2009 with the objective of investigating if the slowdown being measured in other countries is present in the region results show that productivity growth accounts for half of the three fold increase in agricultural output during this period and that performance is sensitive to r d investments in the sector the slowdown found for the 1990s to 2000s in the u s and some european economies does not seem to be present yet in south america the region s total factor productivity tfp growth rate increased steadily from 1 07 during the 1970s to 2 29 during the 2000s given lags in adoption and the adaptive nature of innovations in these economies we have yet to see the potential effects in south american agriculture of decreases in r d in advanced economies

inventory competition under dynamic consumer choice we analyze a model of inventory competition among n firms that provide competing substitutable goods each firm chooses initial inventory levels for their good in a single period newsboy like inventory model customers choose dynamically based on current availability so the inventory levels at one firm affect the demand of all competingfirms this creates a strategic interaction amongthe firms inventory decisions our work extends earlier work on variations of this problem by karjalainen 1992 lippman and mccardle 1997 and parlar 1988 specifically we model demand in a more realistic way as a stochastic sequence of heterogeneous consumers who choose dynamically from amongthe available goods or choose not to purchase based on a utility maximization criterion we also use a sample path analysis so minimal assumptions are imposed on this demand process we characterize the nash equilibrium of the resulting stocking game and prove it is unique in the symmetric case we show there is a bias toward overstocking caused by competition specifically reducing the quantity stocked at any equilibrium of the game increases total system profits and at any joint optimal set of stocking levels each firm has an individual incentive to increase its own stock for the symmetric case we show that as the number of competing firms increases the overstockingbecomes so severe that total system and individual firm profits approach zero finally we propose a stochastic gradient algorithm for computing equilibria and provide several numerical examples

the role of education in facilitating risk taking and innovation in agriculture the impact of education on farmers attitudes toward endogenous risk measured using an attitude survey instrument is estimated with household data from rural ethiopia education of the household head is found to decrease risk aversion next the effects of education and risk attitudes on technology adoption are estimated schooling encourages farmers to adopt innovations whereas risk aversion reduces the probability of adoption thus we find that schooling encourages innovation a potentially risky undertaking not only directly but also indirectly through its effect upon attitudes toward risk to the extent that educated farmers are early innovators and are copied by those with less schooling as other research on the same data has shown the reduction of riskaversion not only has private benefits for those with education but also may have externality benefits

on the relationship between inventory costs and variety benefits in retailassortments consider a category of product variants distinguished by some attribute such as color or flavor a retailer must construct an assortment for the category i e select a subset variants to stock and determine purchase quantities for each offered variant we analyze this problem using a multinomial logit model to describe the consumer choice process and a newsboy model to represent the retailer s inventory cost we show that the optimal assortment has a simple structure and provide insights on how various factors affect the optimal level of assortment variety we also develop a formal definition of the level of fashion in a category using the theory of majorization and examine its implications for category profits

the impact of corporate pollution on market valuation some empirical evidence abstract this paper investigates the relation between the market valuation of publicly listed corporations and their social performance as measured by their pollution record relative to environmental regulations expectations are that corporations with a good bad environmental record should be valued at a premium discount by the stock market such a relation results from the emergence of ethical or green investing and from an increased awareness by investors of the potential negative consequences from corporate environmental damages two significant innovations are introduced in this study first using governmental data a pollution index is computed for each sample firm second the relevance of social information for investors purposes is directly assessed by looking at the relation between the pollution index and a firm s market valuation within the accounting identity framework modigliani and miller 1958 results suggest that a firm s pollution performance is interpreted by market participants as providing information about its environmental liabilities furthermore results weakly support the existence of a premium discount in the stock market valuation of firms that meet do not meet environmental regulations thus lending some credence to the existence of a demand by some stock market participants for ethical or green investments this suggests that the disclosure of audited social information of a non financial nature in a firm s annual report could be beneficial to market participants

human capital entrepreneurship and farm household earnings abstract the allocation of resources between agriculture and non agriculture is a central decision of the farm household in this paper we formulate a profit maximization model in which human capital enhances efficiency through both within sector effects and across sector allocation of quasi fixed inputs the model is estimated using chinese household data that contain detailed information on production activities we find that schooling and experience improve the sectoral uses of household supplied inputs accounting for 27 of their total contribution to earnings the evidence suggests that conventional estimates of human capital returns obtained within sectors would undervalue the role of human capital in development

how does the market value corporate sustainability performance this study provides empirical evidence on how corporate sustainability performance csp as proxied by membership of the dow jones sustainability index is reflected in the market value of equity using a theoretical framework combining institutional perspectives stakeholder theory and resource based perspectives we develop a set of hypotheses that relate the market value of equity to csp for a sample of north american firms our preliminary results show that csp has significant explanatory power for stock prices over the traditional summary accounting measures such as earnings and book value of equity however further analyses suggest that we should not focus on corporate sustainability itself our findings suggest that what investors really do is to penalize large profitable firms with low level of csp firms with incentives to develop a high level of csp not engaging on such strategy are thus penalized by the market

education and off farm work an investigation is presented of the determinants of educational selectivity in a framework that emphasizes the coordination of household members sectoral time allocation is based on members comparative advantage which in turn depends on the utilization and returns to schooling in the farm and nonfarm sectors central to the model is a knowledge spillover hypothesis that workers who participate in off farm work may still contribute knowledge to farm management estimation of the model is based on cross sectional chinese farm household data collected in 1990 from 204 households in sichuan province it is concluded that schooling does not enhance labour productivity when carrying out routine tasks that the contribution to farm efficiency by the most educated members is not affected by their non farm participation and that schooling increases labour market wage rates these empirical results give comparative advantage for the better educated farmers to work off the farm

the effects of education in early stage agriculture some evidence from china the stochastic production frontier approach is used to study the effects of education on agricultural efficiency for a cross section of early stage farms from guanghan county sichuan province china education for farm families in rural china is multifaceted with a combination of formal education intragenerational transfer of knowledge within the home and agricultural extension services since our survey data span two different years with markedly different policy environments we are able to examine not only which aspects of education affect agricultural efficiency but also whether or not the policy environment matters we find limited evidence that in a policy environment that is conducive to agriculture formal education provides positive returns in agriculture furthermore general education may provide greater returns than the more targeted extension services

international comparisons of rural urban educational attainment data and determinants we study cross country differences in rural and urban educational attainment by using a data set comprising 56 countries we focus on the determinants of rural urban educational inequality which is measured by the ratio of rural to urban average years of schooling within each country we find that riskier human capital investment less credit availability a colonial heritage a legal system of french origin and landlockedness of nations are all associated with relatively lower rural educational levels and greater rural urban educational inequality conversely larger formal labor markets better infrastructure and a legal system of british origin are associated with relatively higher rural educational levels and lower rural urban educational inequality we also identify an interaction effect between economic development level and some of these factors in particular we find that as development level increases the negative positive relationship between french british legal systems and rural urban educational inequality is reversed and becomes positive negative

economic development and the role of agricultural technology in earlier debates on economic development the agricultural sector s role was somewhat controversial while dualistic models highlighted the importance of agriculture the mainstream literature placed a greater emphasis on the creation of a modern industrial sector soon agriculture disappeared from the mainstream development literature to re emerge recently with a variety of multiple sector growth models emphasizing the key role of agriculture and specifically technology in agriculture this article is an empirical cross country analysis of agricultural technology s role in economic development specifically the hypothesis being tested is whether improvements in agricultural technology have a significant impact on long run economic growth the results indicate that agricultural modernization has a positive effect on both measures of economic growth and human development

education and allocative efficiency household income growth during rural reforms in china this paper studies the contribution of schooling to rural income in china during factor market liberalization between 1986 and 1995 the relaxation of controls permitted farm households to reallocate productive inputs from agriculture to nonagricultural activities it is hypothesized that education facilitates this adjustment panel data from sichuan province suggest that schooling enhanced the ability of farmers to devote labor and capital to nonfarm production given the evidence that less than optimum levels of these inputs were allocated to nonagricultural uses during the transition the expansion of nonfarm activities contributed significantly to household income growth

multiple product firms a nested logit approach this paper proves the existence of a symmetric equilibrium with multiproduct firms using a nested logit model of demand the demand model is parameterized by two variables that characterize different dimensions of preference for variety these reflect intragroup heterogeneity and intergroup heterogeneity a group or nest being the set of products produced by a firm there are then two dimensions to market performance the total number of firms and the range of products produced per firm it is shown that the market equilibrium involves an excessive number of firms but each firm provides too few products copyright 1992 by blackwell publishing ltd

corporate sustainability ratings an investigation into how corporations use the dow jones sustainability index abstract the purpose of this paper is to explore the use of the dow jones sustainability index djsi with an emphasis on canadian corporations the paper provides insight into the use of the djsi in several areas including the use of its logo the steps taken by corporations to achieve initial acceptance to the index and the steps corporations take to maintain their inclusion in the djsi a content analysis of publicly available information from 24 canadian corporations listed in the djsi north america djsina showed that less than half of those sampled used the djsi logo in their sustainability reports or on their websites the majority of the published references to the djsi were in highlighting corporate achievements or in providing background information on the index a survey of 10 experts from the canadian corporations listed in the djsina revealed a wide range of strategies for gaining and maintaining inclusion in the index particularly involving a large number of internal stakeholders in responding to data requests and working with third parties several suggestions for improving the djsi were also provided including streamlining the questionnaire improving coordination among sustainability ratings agencies and enhancing transparency

assortment planning and inventory decisions under a locational choice model we consider a single period assortment planning and inventory management problem for a retailer using a locational choice model to represent consumer demand we first determine the optimal variety product location and inventory decisions under static substitution and show that the optimal assortment consists of products equally spaced out such that there is no substitution among them regardless of the distribution of consumer preferences the optimal solution can be such that some customers prefer not to buy any product in the assortment and such that the most popular product is not offered we then obtain bounds on profit when customers dynamically substitute using the static substitution for the lower bound and a retailer controlled substitution for the upper bound we thus define two heuristics to solve the problem under dynamic substitution and numerically evaluate their performance this analysis shows the value of modeling dynamic substitution and identifies conditions in which the static substitution solution serves as a good approximation