time consistent public policy in this paper we study how a benevolent government that cannot commit to future policy should trade off the costs and benefits of public expenditure we characterize and solve for markov perfect equilibria of the dynamic game between successive governments the characterization consists of an inter temporal first order condition a generalized euler equation for the government and we use it both to gain insight into the nature of the equilibrium and as a basis for computations for a calibrated economy we find that when the only tax base available to the government is capital income an inelastic source of funds at any point in time the government still refrains from taxing at confiscatory rates we also find that when the only tax base is labour income the markov equilibrium features less public expenditure and lower tax rates than the ramsey equilibrium

understanding heterogeneous preferences in random utility models a latent class approach a finite mixture approach toconditional logit models is developed in whichlatent classes are used to promoteunderstanding of systematic heterogeneity the model is applied to wilderness recreationin which a branded choice experiment involvingchoice of one park from a demand system wasadministered to a sample of recreationists the basis of membership in the classes orsegments in the sample involved attitudinalmeasures of motivations for taking a trip aswell as their stated preferences overwilderness park attributes the econometricanalysis suggested that four classes of peopleexist in the sample using the model toexamine welfare measures of some hypotheticalpolicy changes identified markedly differentwelfare effects than the standard singlesegment model and provided insight into thedifferential impact of alternative policies

rethinking the global food crisis the role of trade shocks although fundamental factors were clearly responsible for shifting the world to a higher food price equilibrium in the years leading up the 2008 food crisis there is little doubt that when food prices peaked in june of 2008 they soared well above the new equilibrium price numerous arguments have been proposed to explain overshooting including financial speculation depreciation of the united states us dollar low interest rates and reductions in grain stocks however observations that international rice prices surged in response to export restrictions by india and vietnam suggested that trade related factors could be an important basis for overshooting especially given the very tangible link between export volumes and export prices in this paper we revisit the trade story by closely examining monthly data from thailand the largest exporter of rice and the united states the largest exporter of wheat and maize and the third largest exporter of soybeans in all cases except soybeans we find that large surges in export volumes preceded the price surges the presence of these large demand surges together with back of the envelope estimates of their price impacts suggests that trade events played a much larger and more pervasive role than previously thought

input demand under yield and revenue insurance previous studies disagree on the effects of insurance on fertilizer application rates the effect of increased fertilizer on the probability of low yields primarily determines whether fertilizer and insurance are substitutes or complements we estimate conditional distributions of corn yields to determine if the technical relationship between yields and fertilizer supports the hypothesis that insurance increases optimal application rates our results indicate no support for this hypothesis at all nitrogen fertilizer rates and reasonable levels of risk aversion nitrogen fertilizer and insurance are substitutes suggesting that those who purchase insurance are likely to decrease nitrogen fertilizer applications

responses to changes in domestic water tariff structures a latent class analysis on household level data from granada spain a problem that affects the estimation of water demand functions is the presence of unobserved individual heterogeneity which means that a common demand function is unlikely to represent the behavior of all users we implement latent class models to estimate water demand functions for four groups of users who are classified according to their unobservable preferences this more flexible approach makes it possible to distinguish four different response patterns to changes in the drivers of water use including different price elasticities these results should be of particular interest to regulators who would like to tailor water demand management policy to heterogeneous users our analysis exploits household level panel data on residential water demand and consumers characteristics obtained by combining information from a survey of 1 465 domestic users in the city of granada and bimonthly price and consumption data supplied by this city s water supplier from the period 2009 2011

the changing technology of technological change general and abstract knowledge and the division of innovative labour abstract in the past most innovations have resulted from empiricist procedures the outcome of each trial yielding knowledge that could not be readily extended to other contexts while trial and error may remain the primary engine of innovation developments in many scientific disciplines along with progress in computational capabilities and instrumentation are encouraging a new approach to industrial research instead of relying purely on trial and error the attempt is also to understand the principles governing the behaviour of objects and structures the result is that relevant information whatever its source can now be cast in frameworks and categories that are more universal the greater universality makes it possible for the innovation process to be organised in new ways firms can specialise and focus upon producing new knowledge and the locus of innovation may be spread across both users and producers more generally the use of general and abstract knowledge in innovation opens up the possibility for a division of labour in inventive activity the division of innovative labour the implications for public policy especially that on intellectual property rights are discussed

wheat storage and trade in an efficient global market domestic and international linkages in speculative stockholdings and trade of wheat are analyzed using a dynamic rational expectations model of the world wheat market dominated by the u s and the eu the results demonstrate the importance of endogenizing both storage and trade in studying commodity markets and suggest that past government stockholdings have not followed efficient market outcomes results indicate that elimination of the export enhancement program by the u s and of export restitution payments by the eu are unlikely to have a major impact on wheat exports from the two regions but will save millions of tax dollars in both regions

the value of ideal contingency markets in agriculture an incomplete markets equilibrium in which no contingency markets are available is compared to a complete markets equilibrium formed by introducing a futures market and a crop insurance market the two regimes are compared using comparative static and welfare analyses numerical examples highlight important characteristics of the model and illustrate how the effects of introducing contingency markets can be quantified the main conclusions are that contingency markets in agriculture increase economic efficiency but there is no guarantee that farmers and consumers both benefit it is found that futures and crop insurance markets may reduce farmer welfare when the demand for farm products is price inelastic

liberalized trade and domestic price stability the case of rice and wheat in india abstract this paper analyzes the effects of liberalizing foodgrain trade on domestic price stability using a multi market equilibrium model in which the direction of trade is determined endogenously and world prices are sensitive to the amount traded by india simulation results demonstrate that contrary to popular belief freeing of trade by india leads to greater domestic price stability even though world prices are more volatile freeing of trade by india also leads to higher world price stability under liberalized trade variable levies subsidies are more effective in stabilizing domestic prices compared to buffer stocks it is therefore in india s interest to argue for non zero binding on import tariffs and export subsidies at the wto negotiations

food inventory policies under liberalized trade abstract this paper evaluates the role of food inventories or buffer stocks in stabilizing prices of foodgrains in india when private external trade in grain is liberalized the model adopts a multi market equilibrium framework with the direction of trade determined endogenously world prices are assumed to be sensitive to the amount traded by india the large country effect the simulation results demonstrate that holding foodgrain inventories is an inefficient mechanism for stabilizing domestic prices under liberalized trade variable levies subsidies on trade appear to be more cost effective freeing of trade lowers domestic price variability even though world prices are more volatile

the choice theory approach to market research this paper surveys economic choice theory stressing developments that permit use of data from psychometric and conjoint experiments to produce market demand forecasts alternatives to the widely used multinomial logit model are summarized and a new method for estimating multinomial probits is described an integration of choice models with attitudinal scaling and perceptual mapping within a latent variable system is described estimation of such systems under either random effects or fixed effects descriptions of heterogeneity across individuals is discussed issues in the use of choice models to describe responses from conjoint experiments are presented new regression diagnostic tests for the consistency of multinomial logit representations are discussed

grain price stabilization in india evaluation of policy alternatives abstract stabilization of prices is an important element of food policy in india as in most other countries both developing and developed however since the magnitude of grain stocks held for this purpose as well as the costs of physical storage have become prohibitively high there is now a need for finding cost effective alternatives including non interventionist and market oriented methods for price stabilization in this paper we consider the case of rice and wheat which are staple foodgrains in india we make a comparison between alternative price stabilization policies including that of holding buffer stocks in terms of their impact on domestic price stability producer and consumer welfare and government costs a multi market equilibrium framework is used where private storage consumption supply and prices of rice and wheat are determined simultaneously indian exports and imports are assumed to affect world prices the alternative price stabilizing mechanisms are ranked according to both the criteria welfare and price stability achieved the main findings are as follows the ranking of alternatives varies with the criterion used greater price stability need not necessarily imply greater welfare the option of variable levies on private external trade turns out to be the most inexpensive and that of domestic buffer stocks the costliest in achieving price stability further the efficacy of buffer stocks and subsidy to private storage in stabilizing prices is lower under free trade as compared to the case where the economy is closed to private external trade

errors in the numerical assessment of the benefits of price stabilization this paper presents a simple computational procedure for determining a consumer s willingness to pay to have a price stabilization policy implemented numerical simulations are then provided which demonstrate that the commonly used expected surplus measures whether hicksian or marshallian can in fact seriously misstate the true benefits of price stabilization these simulations also illustrate the extent to which the results may be dependent upon the assumptions made implicitly or explicitly regarding the consumer s attitudes toward risk thereby underscoring the need to conduct sensitivity analyses to determine the robustness of cost benefit assessments with respect to these assumptions

storage slow transport and the law of one price theory with evidence from nineteenth century u s corn markets abstract this paper argues that localized price spikes should be a regular feature of competitive commodity markets it develops a rational expectations model of physical arbitrage in which trade takes time and shows that inventory management plays a crucial role in the way regional prices are determined in equilibrium arbitrageurs choose export quantities to ensure inventories in the importing center regularly fall to 0 they earn enough profits from high prices on these occasions to offset small losses at other times an analysis of detailed data from chicago and new york corn markets provides empirical support for the model

a simple method of incorporating income effects into logit and nested logit models theory and application substantive income effects are incorporated in a logit or nested logit model by assuming that utility is a piece wise linear spline function of residual income specific income data are not require

a finite mixture logit model of recreational angling with serially correlated random utility this article examines two issues concerning the trip taking behavior of recreational anglers over the course of a season the first is whether the random component of trip utility is serially correlated across trip occasions the second is the heterogeneity of preferences among anglers recent research has examined heterogeneity among recreational trip takers using random parameters models in this article the population of anglers is instead cast as a collection of several subpopulations distinguished by angler preferences and the method of finite mixtures is used to identify these subpopulations copyright 2002 oxford university press

the effects of commodity price stabilization programs in this paper the authors analyze the effects of commodity programs in which the government attempts to support and stabilize price through open market purchases and sales specifically they as sess the effects of such programs on the u s soybean market using a rational expectations model that allows for private storage expected price responsive production and arbitrary support and release price s a salient feature of the model is that private storage and product ion behavior adjusts to changes in government policy stochastic simu lations of the market model demonstrate that price stabilization prog rams can reduce long run market price and destabilize producer revenu e copyright 1988 by american economic association

sectoral patterns of technical change towards a taxonomy and a theory abstract the purpose of the paper is to describe and explain sectoral patterns of technical change as revealed by data on about 2000 significant innovations in britain since 1945 most technological knowledge turns out not to be information that is generally applicable and easily reproducible but specific to firms and applications cumulative in development and varied amongst sectors in source and direction innovating firms principally in electronics and chemicals are relatively big and they develop innovations over a wide range of specific product groups within their principal sector but relatively few outside firms principally in mechanical and instrument engineering are relatively small and specialised and they exist in symbiosis with large firms in scale intensive sectors like metal manufacture and vehicles who make a significant contribution to their own process technology in textile firms on the other hand most process innovations come from suppliers these characteristics and variations can be classified in a three part taxonomy based on firms 1 supplier dominated 2 production intensive 3 science based they can be explained by sources of technology requirements of users and possibilities for appropriation this explanation has implications for our understanding of the sources and directions of technical change firms diversification behaviour the dynamic relationship between technology and industrial structure and the formation of technological skills and advantages at the level of the firm the region and the country

the digital provide information technology market performance and welfare in the south indian fisheries sector when information is limited or costly agents are unable to engage in optimal arbitrage excess price dispersion across markets can arise and goods may not be allocated efficiently in this setting information technologies may improve market performance and increase welfare between 1997 and 2001 mobile phone service was introduced throughout kerala a state in india with a large fishing industry using microlevel survey data we show that the adoption of mobile phones by fishermen and wholesalers was associated with a dramatic reduction in price dispersion the complete elimination of waste and near perfect adherence to the law of one price both consumer and producer welfare increased

the law of one price intranational evidence for canada this study investigates the behaviour of intranational prices for 45 specific consumer goods across 25 canadian cities it finds positive roles for distance and provincial borders in intercity price disparities while sizable the provincial border effect is an order of magnitude smaller than the estimates for the canada u s border a majority of the intercity relative price series are stationary around small mean values indicating that long run price differences are close to zero the intercity prices converge at rates considerably faster than the consensus estimates for international prices in fact half lives for intercity price deviations average well under a year jel classification f15 f31 la loi d un seul prix resultats intra nationaux pour le canada ce memoire examine le comportement des prix intra nationaux de 45 biens de consommation specifiques dans 25 villes canadiennes il semble que la distance et les frontieres inter provinciales ont un impact sur les differentiels de prix entre villes meme si l impact des frontieres inter provinciales est important il est beaucoupplus petit que l impact de la frontiere canada u s une majorite des series de prix relatifs entre villes sont stationnaires autour de petites valeurs moyennes ce qui suggere que les differences de prix a long terme s approchent de zero il est clair que les prix entre villes convergent a des taux considerablement plus rapides que ce qu on observe au niveau international en fait les deviations de prix entre villes ont une esperance de vie qui en moyenne est de moins d un an

price dynamics in the bangladesh rice market implications for public intervention in this paper the price dynamics of a rice market are examined using dynamic programming techniques the model is parameterised to the case of bangladesh and thus represents the situation of a very poor country which has characteristically high price elasticity due to income effects and high storage and interest costs the incentives for private sector storage and its impact on price stability are examined various options for public intervention in the storage sector are also explored including price ceiling schemes and subsidisation of storage costs results show that interventions that remove private disincentives such as storage subsidies are much cheaper than direct intervention by government but the impact on the probability distribution of prices is quite different the effect of trade on the probability distribution of prices is also examined

who cares about environmental stigmas and does it matter a latent segmentation analysis of stated preferences for real estate this article uses latent segmentation analysis to estimate the benefits of contaminant cleanup in waukegan harbor illinois survey responses to attitudinal and perception questions provide significant information about the existence of distinct preference groups by comparison the predictive usefulness of demographic covariates is unclear the expected aggregate willingness to pay of waukegan homeowners for full cleanup is approximately equivalent to a 20 increase in the market value of homes the aggregate estimate is little affected by the identification of preference clusters

exact consumer s surplus and deadweight loss consumer s surplus is a widely used tool in applied welfare economics both economic theorists and cost benefit analysis often use consumer s surplus despite its somewhat dubious reputation the basic idea is to evaluate the value to a consumer or his willingness to pay for a change in price of a good from say pricep to pricep because price changes affect consumer welfare an evaluation of this effect is often a key input to public policy decisions yet consumer s surplus is probably the most controversial of widely used economic concepts both paul samuelson and ian little conclude that the economics profession would be better off without it it is my feeling of the situation that substantial agreement exists on the correct quantities to be measured the amount the consumer would pay or would need to be paid to be just as well off after the price change as he was before the price change the quantities correspond to john hicks compensating variation measures an alternative measure which takes ex post price change utility as the basis of comparison is hicks equivalent variation the controversy arises in the measurement of these quantities the usual measurement procedure is to use the area to the left of the marshallian market demand curve between two price levels jules dupuit originated this measure of welfare change and alfred marshall and hicks derived appropriate conditions for its use the primary condition for the area to the left of the demand curve to correspond to the compensating variation is to have constant marginal utility of income marshall gave this condition and if it holds the same quantity will be derived as the area to the left of the compensated hicksian demand curve this area to the left of the compensated demand curve is exactly what the compensating variation and equivalent variation measure thus the constant marginal utility of income is a sufficient condition for marshallian consumer s surplus to be equal to hicks consumer s surplus in this case arnold harberger s plea to use the welfare triangle as one half times the product of the price change times the quantity change to measure deadweight loss corresponds to the correct theoretical amount of welfare change in a recent paper robert willig derives bounds for the percentage difference between the correct measure of either the compensating or equivalent variation and the marshallian measure derived form the market demand curve his bounds which depend on the income elasticity of demand for the single good in the region of price change being considered as well as the proportion of the consumer s income spent on the good demonstrate that the marshallian consumer s surplus is often a good approximation to hicks consumer s surplus the fact that the proportion of the consumer s income spent matters as well as the income elasticity was first pointed out by harold hotelling willig contends that the approximation error will be less than the errors involved in estimating the demand curve thus he hopes to remove the need for apology that applied economists often need to give to theorists who remark on the inappropriateness of using marshallian consumer s surplus to measure welfare change however in this paper i show that for the case primarily considered by willig of a single price change which is also the situation in which consumer s surplus is often used in applied work no approximation is necessary professor of economics massachusetts institute of technology and research associate national bureau of economic research i would like to thank peter diamond erwin diewert daniel mcfadden robert merton robert solow hal varian joel yellin and the referees for help and comments research support from the national science foundation is acknowledged the reason that we still have two rather than one of samuelson s six measures of consumer s surplus arises from an index number problem of the correct basis for the welfare comparison i will give both measures but plan to concentrate on the compensating variation

steady change the 200 largest us manufacturing firms throughout the 20th century this paper discusses the existence of structural change in business activity and technological competence among the 200 largest us manufacturing companies throughout the 20th century the data were taken from chandler scale and scope 1990 and fortune magazine the analysis of corporate evolution in used to assess continuity versus turbulence of business organizations in the context of the neo schumpeterian long wave hypothesis the empirical results show that the giants of the late 20th century are not the same as those at the beginning of that period persistence in the sample is very limited moreover turbulence is not smooth but rather occurs by impulses that affect specific industries and it has increased over time overall the pattern of corporate entry and industry development is very indicative of the new opportunities emerging with information and communication technologies this process of open ended continuous transformation supports the case for putting change at the centre of economic analysis

oligopolistic pricing with sequential consumer search n identical stores compete by choosing prices for a homogeneous good with constant marginal costs consumers search sequentially with perfect recall for the lowest price one class of consumers called shoppers have zero search costs while all other consumers have a positive search cost c there is a unique symmetric nash equilibrium price distribution with the property that it changes smoothly from marginal cost pricing when all consumers are shoppers and or c 0 and monopoly pricing when no consumers are shoppers remarkably as the number of stores increases the nash equilibrium becomes more monopolistic copyright 1989 by american economic association

optimal food price stabilization in a small open developing country in poor countries most governments implement policies aiming to stabilize the prices of staple foods which often include storage and trade measures insulating their domestic market from the world market it is of crucial importance to understand the precise motivations and efficiency of those interventions because they can have consequences worldwide this paper addresses those issues by analyzing the case of a small open developing country confronted by shocks to both the crop yield and foreign price in this model government interventions may be justified by the lack of an insurance market for food prices considering this market imperfection the authors design optimal public interventions through trade and storage policies they show that an optimal trade policy largely consists of subsidizing imports and taxing exports which benefits consumers at the expense of producers import subsidies alleviate the non negativity of food storage in other words when stocks are exhausted subsidizing imports prevents domestic price spikes one striking result an optimal storage policy on its own is detrimental to consumers since its stabilizing benefits leak into the world market and it raises the average domestic price by contrast an optimal combination of storage and trade policies results in a powerful stabilizing effect for domestic food prices

trade and insurance with moral hazard abstract previous literature on the use of trade policy for insurance has relied implicitly on moral hazard and adverse selection as the reasons for the failure of private markets for risk bearing this paper begins with the observation that such forces should be incorporated explicitly into the models to ensure a fair comparison between markets and governments for the case of moral hazard it is found that market equilibrium given exclusive insurance is an informationally constrained pareto optimum in one case of non exclusive insurance a systematic role for government insurance is found but the scope of trade policy is ambiguous

on the sources and significance of interindustry differences in technological opportunities abstract the set of technological opportunities in a given industry is one of the fundamental determinants of technical advance in that line of business we examine the concept of technological opportunity and discuss three categories of sources of those opportunities advances in scientific understanding and technique technological advances originating in other industries and in other private and governmental institutions and feedbacks from an industry s own technological advances data from the yale survey on industrial research and development are used to measure the strength of various sources of technological opportunity and to discern interindustry differences in the importance of these sources we find that interindustry differences in the strength and sources of technological opportunities contribute importantly to explanations of cross industry variation in r d intensity and technological advance

trade and insurance with adverse selection this paper considers a small open economy with a safe sector and a risky sector the probability of success in the risky activity differs across individuals and is private information it is shown that policies that sustain informationally constrained pareto optima should not include tariffs a laissez faire competitive equilibrium if it exists is pareto optimal these results contrast with previous literature on the role of tariffs as insurance where private risk markets are assumed away in an ad hoc manner

expected consumer s surplus and the welfare effects of price stabilization suppose a consumer faces a price which is uncertain ex ante a question which often arises is whether the consumer would benefit from a stabilization policy under which the price would then be fixed and known with certainty many authors have addressed this question by calculating the expected compensating variation of the price change others have used expected marshallian consumer s surplus often with the explanation that it is a good approximation to expected compensating variation 2 an important unresolved issue however is whether expected compensating variation does in fact provide a valid ranking of stochastic prices against stabilized prices i e a ranking in agreement with that given by expected utility in section 2 we demonstrate that expected compensating variation is not in general a valid utility indicator in essence while utility comparisons under uncertainty require the use of the cardinal properties of von neumannmorgenstern utility functions the expected surplus measures depend only on ordinal preference rankings expected compensating variation then is completely insensitive to and cannot reflect the precise factor of interest in suchstudies the consumer s attitudes toward risk we then derive a set of restrictions on the utility function which are necessary in order for expected compensating variation to be a valid measure we see that price stabilization policies can only be evaluated with compensating variation if consumer preferences are assumed to satisfy quite stringent requirements this is in constrast to the familiar certainty case in which compensating variation always provides correct rankings

the inefficiency of interest rate subsidies in commodity price stabilization interest rate subsidies have been used to stimulate commodity stockholding with the intention of stabilizing prices however reductions in price variability can be achieved at less government cost using a direct storage subsidy and it is possible that an interest rate subsidy will increase price variability even though the interest subsidy increases mean stocks held these results are demonstrated using a stochastic dynamic programming model of optimal private storage with parameter values relevant to agricultural commodity markets and with particular reference to the u s soybean market

chandlerism in post war europe strategic and structural change in france germany and the uk 1950 1993 this paper examines the chandlerian model of corporate development in the light of new data on the strategies and structures of large european firms in the post war period conglomerate strategies continue to spread but these are typically less stable than strategies of related diversification the divisional structure now predominates in europe suppressing more indigenous forms the paper discusses implications both for economic arguments around the resource based view of the firm and for institutionalist arguments around the spread of american management ideas the paper concludes that chandler s original model is remarkably robust to both change over time and differences across countries copyright 1999 by oxford university press

combining discrete and continuous representations of preference heterogeneity a latent class approach unobserved preference heterogeneity has been widely recognized as a critical issue not only for modelling choice behaviour but also for policy analysis this paper examines alternative approaches for incorporating heterogeneity in recreational demand we apply a hybrid model combining discrete and continuous heterogeneity representations of tastes to capture the defining features of both the latent class and the random parameter logit specifications this model allows for the joint estimation of discrete segments and within segment heterogeneity providing a richer interpretation of preference heterogeneity a database of recreational trips to forest sites in mallorca has been used to compare the empirical performance of this hybrid approach with common specifications such as the conditional logit the random parameter logit and the latent class model

stigmatized asset value is it temporary or long term stigma is a negative attribute of real estate acquired by environmental contamination and reflected in its value elliot jones 1996 using a model of neighborhood turnover with external economies we show that both temporary stigma and long term stigma are possible equilibrium outcomes after the discovery and cleanup of a hazardous waste site the existence and duration of stigma are examined using hedonic price techniques with data from housing sales prices in dallas county texas we find that results depend critically on distance from the hazardous waste site neighborhood turnover due to changes in the level of poverty also appears likely

the theory of the knowledge creating firm subjectivity objectivity and synthesis the theory of the knowledge creating firm explains the differences among firms not as a result of market failure but as a result of the firm s visions of the future and strategy this paper proposes a framework to capture the dynamic process of knowledge creation in which knowledge is created through the dynamic interaction between subjectivity and objectivity knowledge is created through the synthesis of thinking and actions of individuals who interact with each other within and beyond the organizational boundaries

the technological competencies of the world s largest firms complex and path dependent but not much variety firm specific technological competencies help explain why firms are different how they change over time and whether or not they are capable of remaining competitive data on more than 400 of the world s largest firms show that their technological competencies have the following characteristics 1 1 they are typically multi field and becoming more so over time with competencies ranging beyond their product range in technical fields outside their distinctive core 2 2 they are highly stable and differentiated with both the technology profile and the directions of localised search strongly influenced by firms principal products 3 3 the rate of search is influenced by both the firm s principal products and the conditions in its home country however considerable unexplained variance suggests scope for managerial choice these findings confirm the importance of complexity and path dependency in the accumulation of firm specific technological competencies and show that managers are heavily constrained in the directions of their technological search they also show the limits of the notion of competition through variety given that the same specific field of technological competence is often essential to the development of a range of possible product configurations technological imperatives still exist

social stigma and asset value recent attempts by economists to identify and quantify the effect of social stigma on asset value have often been stymied by confounding mechanisms i use the unique circumstances surrounding the 1999 columbine shooting to estimate the effect of social stigma on asset value using a difference in differences model with property fixed effects i find the immediate effect of stigma from the columbine shooting is 5 7 of a property s value after one year this implies a 13 million loss from property sales in the year 2000 alone the results are robust to numerous specifications and synthetic control placebo tests this suggests that social stigma plays a role in consumer preferences

the economic role of commodity storage one of the earliest and most successful exainples of economic policy is the oftquoted biblical account of joseph s interpretation of the pharoah s dream joseph foretold that seven years of abundant harvests would precede seven years of drought and recommended that the pharoah accumulate grain during the good years since that time the central role of storage in stabilising the economy in the face of exogenous disturbances has been obvious but our understanding of the nature of that role has not greatly advanced without divine assistance in forecasting stochastic production the storage decision is considerably more complex than the one joseph faced and the role of storage quite different in fact several commonly held impressions about the role of storage of commodities such as grains are incorrect rather than stabilising production storage actually accentuates its variability rather than causing a mean price preserving decrease or a mean output preserving decrease in the dispersion of price storage generally causes a more complex modification of the distribution of price rather than being most effective at eliminating short falls in consumption storage actually is more effective at eliminating the incidence of exceedingly high consumption in this paper we explore the role of storage in a model where production is stochastic and both production and storage are performed by competitive profitmaximisers who form rational expectations about the returns to their activities we derive the subtle but very important interactions among production price expectations and storage which simpler models cannot capture finally we make a comparative statics assessment of the distributional implications of storage these results while confirming the importance of the specification of the demand function and the supply elasticity identified in recent analytical studies e g wright i979 and newbery and stiglitz i979 are surprisingly favourable to consumers considering the asymmetric nature of the effects of storage on consumption and price storage is simply a productive activity one that transfers a commodity from one period to the next like other forms of production it is costly the total cost of storing an amount st from period t to period t i is as of period t i

a joint latent class model combining likert scale preference statements with choice data to harvest preference heterogeneity in addition to choice questions revealed and stated choices preference surveys typically include other questions that provide information about preferences preference statement data include questions on the importance of different attributes of a good or the extent of agreement with a particular statement the intent of this paper is to model and jointly estimate preference heterogeneity using stated preference choice data and preference statement data the starting point for this analysis is the belief that the individual has preferences and both his her choices and preference statements are manifestations of those preferences our modeling contribution is linking the choice data and preference statement data in a latent class framework estimation is straightforward using the e m algorithm even though our model has hundreds of preference parameters our estimates demonstrate that 1 within a preference class the importance anglers associate with different green bay site characteristics is in accordance with their responses to the preference statements 2 estimated across class utility parameters for fishing green bay are affected by the preference statement data 3 estimated across class preference statement response probabilities are affected by the inclusion of the choice data and 4 both data sets influence the number of classes and the probability of belonging to a class as a function of the individual s type

using angler characteristics and attitudinal data to identify environmental preference classes a latent class model a latent class model of environmental preference groups is developed and estimated with only the answers to a set of attitudinal questions economists do not typically use this type of data in estimation group membership is latent unobserved the intent is to identify and characterize heterogeneity in the preferences for environmental amenities in terms of a small number of preference groups the application is to preferences over the fishing characteristics of green bay anglers answered a number of attitudinal questions including the importance of boat fees species catch rates and fish consumption advisories on site choice the results suggest that green bay anglers separate into a small number of distinct classes with varying preferences and willingness to pay for a pcb free green bay the probability that an angler belongs to each class is estimated as function of observable characteristics of the individual estimation is with the expectation maximization e m algorithm a technique new to environmental economics that can be used to do maximum likelihood estimation with incomplete information as explained a latent class model estimated with attitudinal data can be melded with a latent class choice model

the effects of rural electrification on employment new evidence from south africa this paper estimates the impact of electrification on employment growth by analyzing south africa s mass roll out of electricity to rural households using several new data sources and two different identification strategies an instrumental variables strategy and a fixed effects approach i find that electrification significantly raises female employment within five years this new infrastructure appears to increase hours of work for men and women while reducing female wages and increasing male earnings several pieces of evidence suggest that household electrification raises employment by releasing women from home production and enabling microenterprises migration behavior may also be affected jel h54 l94

learning from the crowd regression discontinuity estimates of the effects of an online review database internet review forums increasingly supplement expert opinion and social networks in informing consumers about product quality however limited empirical evidence links digital word of mouth to purchasing decisions we implement a regression discontinuity design to estimate the effect of positive yelp com ratings on restaurant reservation availability an extra half star rating causes restaurants to sell out 19 percentage points 49 more frequently with larger impacts when alternate information is more scarce these returns suggest that restaurateurs face incentives to leave fake reviews but a rich set of robustness checks confirm that restaurants do not manipulate ratings in a confounding discontinuous manner

random coefficient models for stated preference surveys abstract this paper combines the use of random coefficient discrete choice models that allow for correlated errors in the form of unobserved preference heterogeneity with an investigation of the reliability and usefulness of rankings data for the data we examine we find significant unobserved preference heterogeneity in the rankings which violates the underlying assumptions of the rank ordered logit model further directly modeling unobserved preference heterogeneity results in significant improvement in the precision of the parameter estimates and in estimated willingness to pay wtp the reliability and usefulness of rankings data should be re examined with econometric models not subject to the independence of irrelevant alternatives iia

a structural decomposition analysis of technological opportunity corporate survival and leadership this article considers corporate technological leadership and survival in the face of changing technological opportunities over the period 1930 1990 for firms selected from three broad industrial groups by using us patent data in a novel application of structural decomposition analysis it considers the extent to which selected firms positions of technological leadership benefited from a favorable change in the structure of their technological environment relative to changes caused through firm level choices copyright 2007 oxford university press

recreation demand models with taste differences over people we estimate random parameter logit models of anglers choice of fishing site the models generalize logit by allowing coefficients to vary randomly over anglers rather than being fixed the models do not exhibit the restrictive independence from irrelevant alternatives property of logit and can represent any substitution pattern estimation explicitly accounts for the fact that the variation in coefficients over anglers induces correlation in unobserved utility over trips by the same angler willingness to pay for improved fish stock and the value to anglers of specific sites are calculated from the models and compared with the estimates obtained from a standard logit model

export restrictions and price insulation during commodity price booms for individual countries variable trade barriers can be used to reduce the volatility of domestic relative to world prices if this is done by countries accounting for a large share of the market its effect is offset by increases in world price volatility this study shows the nature of the resulting collective action problem with the policy being ineffective on average in stabilizing domestic prices while increasing the volatility of the income transfers from terms of trade changes a simple approach to assessing the contribution of insulation to the price increases is developed and used with new estimates of agricultural distortions to assess its contribution to the price spikes in 1972 74 and 2006 08 for rice and wheat the analysis suggests that 45 percent of the increase in rice prices in 2006 08 and 30 percent of the increase in wheat prices was due to insulating behavior one sign of progress since 1972 74 was a substantial reduction in the extent of price insulating behavior by the industrial countries this provides little stabilizing benefit in the rice market because countries not classifying themselves at the world trade organization as developing account for only 3 percent of world rice consumption but it does offer some benefit for the wheat market where non developing countries account for 27 percent of consumption

mobile phones and economic development in rural peru the authors estimate the effects of mobile phone coverage on different measures of economic development the authors exploit the timing of mobile coverage at the village level merging it with a village level panel dataset for rural peru the main findings suggest that mobile phone expansion has increased household real consumption by 11 percent reduced poverty incidence by 8 percentage points and decreased extreme poverty by 5 4 percentage points moreover those benefits appear to be shared by all covered households regardless of mobile ownership

nonparametric bounds on treatment effects assume that each member of a population is characterized by values for the variables ya yb z x here x is a vector describing a person and z is a binary variable indicating which of two treatments this person receives the treatments are labelled a and b the variables ya and yb are scalar measures of the outcomes of the two treatments for example a cancer patient might be treated by a drug therapy or b surgery the relevant outcome y might be life span following treatment an unemployed worker might be given a vocational training or b job search assistance here the relevant outcome might be labor force status following treatment assume that a random sample is drawn and that one observes the realizations of z x and of the outcome under the treatment received thus ya is observed if treatment a is received but is a latent variable if treatment b is received similarly yb is either observed or latent suppose that one wants to learn the difference in expected outcome if all persons with attributes x were assigned to treatment a or b this treatment effect is

the method of constant market shares analysis reconsidered constant market shares cms analyses are frequently used in applied studies of export development this paper reviews the development of the method and argues that it can be considerably improved a new version of the method is developed which in addition to the familiar cms effects also allows for the calculation of effects reflecting the ability of each country to adapt its export structure to the changes in the commodity and country composition of world imports the method is applied to a sample of 20 oecd countries for the period 1961 83

the vanishing hand the changing dynamics of industrial capitalism alfred chandler s portrayal of the managerial revolution of the late nineteenth and early twentieth centuries does not extend well into the late twentieth century when widespread vertical disintegration began replacing the classical multi unit managerial enterprise this paper attempts to explain the new economy in a manner consistent with chandler by providing an enlarged theoretical account of industrial evolution in this account clusters of chandlerian firms appeared as a temporary episode within a larger smithian process of the division of labor

optimal food price stabilisation policy this paper proposes a framework for designing optimal food price stabilisation policies in a self sufficient developing country it uses a rational expectations storage model with risk averse consumers and incomplete markets government stabilises food prices by carrying public stock and by applying a state contingent subsidy tax to production the policy rules are designed to maximise intertemporal welfare the optimal policy under commitment crowds out all private stockholding activity by removing the profit opportunity from speculation the countercyclical subsidy tax to production helps price stabilisation by subsidising production in periods of scarcity and by taxing it in periods of glut it contributes little to welfare gains most of which come from stabilisation achieved through public storage

food price policy the rationale for government intervention abstract policy makers in the most successful developing countries have not accepted either of the two major schools of thought on food price policy the neo classical school favours free trade to maximize efficiency of resource allocation the structuralist school favours interventions to satisfy goals for income distribution especially in the rapidly growing rice based economies of asia policy makers have been more concerned about stability of domestic prices than their level relative to world prices this concern traditionally dismissed by economists as purely political is justified on economic grounds because of improved macroeconomic and dynamic efficiency from stable food prices the paper identifies both the benefits from food price stability and the costs of achieving it

the underemphasized role of established firms as the sources of major innovations we argue that established firms including industry incumbents and diversifying entrants play vital all underemphasized roles as the sources of major innovations in many industries the study presents empirical evidence showing that established firms are often sources of major innovations in the telecommunications and medical sectors we conduct an exploratory investigation of how variation in the types of technical and market change influence whether industry incumbents diversifying entrants or nets companies are the sources of major innovations copyright 1996 by oxford university press