the effect of the food stamp program on nutrient intake i introduction one of the goals of the food stamp program as stated in the preamble of the law is to ensure that low income households have the opportunity to attain a nutritionally adequate diet previous economic studies evaluating the effects of food stamp income on nutrient intake have typically found a positive usually small correlation between the receipt of food stamps and nutrition two recent papers by devaney and moffitt 1991 and horton and campbell 1991 reach very positive conclusions concerning the effect of income in general papers from the nutrition literature generally find positive but weak and often insignificant effects of income on nutrition we employ information on two groups of low income people and find slightly different results for the two groups but very different results from many of the other studies for a sample of rural families taken from data from the rural income maintenance experiment we find almost no effect of food stamp income or evidence of selection bias 1 however for a sample of elderly people from the food stamp cashout project we find strong evidence that self selection into the food stamp program is highly correlated with attaining nutritional adequacy and that controlling for the self selection food stamp income and other income have a negative effect on nutrition we re examine the relationship between food stamp income and the nutrient intake of the poor and improve upon the existing literature in several important ways first it is possible that the positive correlation between the receipt of food stamps and nutrition is not a direct causal link but rather is the result of other factors affecting both for example in one of the samples examined in this paper only 50 percent of those eligible actually apply for and receive food stamps it could be the case that those who care more about nutrition are at the same time more likely to apply for and receive food stamps and more likely to maintain a nutritionally adequate diet these possible self selection problems can be disentangled from possible direct effects of food stamp income on nutrition using estimation procedures which correct for selection bias another issue which our research addresses is that the level of one nutrient may be correlated with the levels of other nutrients this may occur either because individuals who care about nutrition may be more likely to attain adequate levels of all nutrients or because combinations of nutrients occur naturally in foods we posit a multi equation model of the levels of nutrients and allow the disturbances in each equation to be correlated none of the previous studies considered this correlation finally we recognize the fact that above some level extra nutrients are superfluous if an individual has attained a nutritionally adequate diet then whether or not food stamp income allows him or her to consume more nutrients is irrelevant we are primarily interested in therefore whether or not an individual attains an adequate level of a nutrient rather than the absolute amount of a nutrient consumed in previous studies devaney and moffitt 1991 had addressed simultaneously the issues of selection bias and the superfluity of nutrients above some level the finding that food stamp income actually lowers nutrient intake ceteris paribus is a novel result for studies of the food stamp program but it would not be novel in the literature on nutrition in less developed countries pitt and rosenzweig 1985 behrman and deolalikar 1987 it is reasonable to believe that as income increases households employ relatively more money than time in household production this is silberberg s 1985 explanation for decreased efficiency in producing pure nutrients in other words as income increases people spend less time preparing meals and more money on foods which are easier to prepare if as is often the case foods which are more convenient to prepare are less nutritious than foods which require a lot of time to prepare then our result is not surprising

limit order book as a market for liquidity we develop a dynamic model of an order driven market populated by discretionary liquidity traders these traders must trade yet can choose the type of order and are fully strategic in their decision traders differ by their impatience less patient traders demand liquidity more patient traders provide it three equilibrium patterns are obtained the pattern is determined by three parameters the degree of impatience of the patient traders which we model as the cost of execution delay in providing liquidity their proportion in the population which determines the degree of competition among the liquidity providers and the tick size which is the cost of the minimal price improvement despite its simplicity the model generates a rich set of empirical predictions on the relation between market parameters time to execution and spreads we argue that the economic intuition of this model is so basic its main results must be robust in much more general models

impact of income on nutrient intakes implications for undernourishment and obesity the relationship between income and nutrient intake is explored nonparametric panel and quantile regressions are used engle curves for calories fat and protein are approximately linear in logs with carbohydrate intakes exhibiting diminishing elasticities as incomes increase elasticities range from 0 10 to 0 25 with fat having the highest elasticities countries in higher quantiles have lower elasticities than those in lower quantiles results predict significant cumulative increases in calorie consumption which are increasingly composed of fats though policies aimed at poverty alleviation and economic growth may assuage hunger and malnutrition they may also exacerbate problems associated with obesity

crises food prices and the income elasticity of micronutrients estimates from indonesia the 2008 global food price crisis and more recent food price spikes have led to a greater focus on policies and programs to cushion the effects of such shocks on poverty and malnutrition analysis of the income elasticities of micronutrients and their changes during food price crises can shed light on the potential effectiveness of cash transfer and nutrition supplement programs this article examines these issues using data from two cross sectional household surveys in indonesia taken before 1996 and soon after 1999 the 1997 98 economic crisis which led to a sharp increase in food prices first using nonparametric and regression methods the article examines how the income elasticity of calories from starchy staples as a share of total calories differs between the two survey rounds second the article estimates income elasticities of important nutrients in indonesia the analysis finds that although summary measures such as the income elasticity of the starchy staple ratio might not change during crises this stability masks important differences across individual nutrients in particular income elasticities of some key micronutrients such as iron calcium and vitamin b1 are significantly higher in a crisis year than in a normal year yet the income elasticities of others such as vitamin c remain close to zero these results suggest that cash transfer programs might be even more effective during crises to ensure the consumption of essential micronutrients but to ensure that all key micronutrients are consumed nutrition supplement programs are also likely required jel classification codes i12 o12 d12 e31 keywords income elasticity crisis prices micronutrients vitamin c starchy staple ratio

the economics of two sided markets at a local best buy a child places a new sony playstation 3 on the cashier s counter while the parents dig out their visa card the gaming system and the payment card may appear to have little connection other than this purchase however these two items share an important characteristic that is generating a series of economic insights and has important implications for strategic decision making and economic policymaking both video game systems and payment cards are examples of two sided markets broadly speaking a two sided market is one in which 1 two sets of agents interact through an intermediary or platform and 2 the decisions of each set of agents affects the outcomes of the other set of agents typically through an externality in the case of a video game system the intermediary is the console producer sony in the scenario above while the two sets of agents are consumers and video game developers neither consumers nor game developers will be interested in the playstation if the other party is not similarly a successful payment card requires both consumer usage and merchant acceptance where both consumers and merchants value each others participation many more products fit into this paradigm such as search engines newspapers and almost any advertisersupported media examples in which consumers often negatively value rather than positively value the participation of the other side as well as most software or title based operating systems and consumer electronics malls which seek retailers and consumers convention organizers which seek buyers and sellers dating services which seek men and women and the journal of economic perspectives which seeks content and readership all experience the economics of two sided markets the multi sided nature of many internet and high technology markets as well as

comparing the post earnings announcement drift for surprises calculated from analyst and time series forecasts post earnings announcement drift is the tendency for a stock s cumulative abnormal returns to drift in the direction of an earnings surprise for several weeks following an earnings announcement we show that the drift is significantly larger when defining the earnings surprise using analysts forecasts and actual earnings from i b e s than when using a time series model based on compustat earnings data neither compustat s policy of restating earnings nor the inclusion of special items in reported earnings contribute significantly to the disparity in drift magnitudes rather our results suggest that this disparity is attributable to differences between analyst forecasts and those of time series models or at least to factors correlated with these differences further we document that analyst forecasts lead to return patterns around future earnings announcements that differ from those observed when using time series models suggesting that the two types of surprises may capture somewhat different forms of mispricing

execution risk in high frequency arbitrage in this paper we investigate the role of execution risk in high frequency trading through arbitrage strategies we show that if rational agents face uncertainty about completing their arbitrage portfolios then arbitrage is limited even in markets with perfect substitutes and convertibility using a simple model we demonstrate that this risk arises from the crowding effect of competing arbitrageurs entering the same trade and inflicting negative externalities on each other our empirical results provide evidence that support the relevance of execution risk in high frequency arbitrage this paper was accepted by wei xiong finance

a probit latent variable model of nutrition information and dietary fiber intake nutrition information and intake data for a sample of u s household meal planners are used to estimate the effects of fiber specific information on dietary fiber intake the information variables are measured using survey questions on fiber content of foods attitude toward consuming fiber rich foods and awareness of fiber health links the evidence confirms the influence of nutrition information on fiber intake household income meal planner age smoking status vegetarian status race and ethnicity are major determinants of both information and intake education exerts a sizable intake effect by enhancing the information level direct and indirect effects of exogenous variables are reported

trading volume and asset liquidity since the depth and liquidity of a market depend on the entry decisions of all potential participants each trader assesses them according to conjectures about entry by others if trade is equally costly across markets this externality leads to the concentration of trade on one market if not it can produce multiple conjectural equilibria some where trade concentrates on one market and others where large traders resort to a separate market or to search for a trading partner while fragmentation is welfare reducing in the two market case no such ranking is possible if it involves off exchange search

prices and quality effects in cross sectional demand analysis a conceptual clarification of the sources and meaning of cross sectional price variability is used to motivate a theoretical and econometric framework for the estimation of cross sectional demand functions quality effects are distinguished from supply related price variability to identify cross sectional demand for disaggregated food commodities an empirical application using data from the 1977 78 nationwide food consumption survey indicates that parameter differences resulting from a failure to adjust cross sectional prices for quality effects are likely to be small for relatively homogenous disaggregated food commodities in demand analysis with cross sectional household budget data it is usually assumed that prices are constant allen and bowley prais and houthakker george and king given this assumption engel functions are estimated where expenditure or quantity is regressed on income or total expenditures family size and other demographic characteristics the assumption that cross sectional price effects are absent or are captured adequately by spatial and temporal dummy variables has not been evaluated empirically whether cross sectional price effects can be treated in this manner has implications for the specification of cross sectional demand functions as well as the estimation of engel functions there is a considerable literature on estimating price elasticities with cross sectional data most of the applications utilize timeseries cross sectional data annual or quarterly household consumption surveys and

an emprical model of the demand for a varied diet this study attempts to measure some aspects of the household s demand for a varied die by invesigaing how he number of individual foods consumed b he household is affeced b is preferences and food expendiure a heoriical model suggesed b household production theory is adopted to empirical data from a cross section of households it is found that the number of individual foods consumed is strongly responsive to househjold expenditure on all foods

cross sided liquidity externalities we study the empirical relevance of the participation externality between liquidity suppliers makers and demanders takers i e whether liquidity demand attracts or reduces liquidity supply and vice versa we use exogenous shocks to exchange fees and technology as experiments to identify cross sided complementarities between liquidity suppliers and demanders in the u s equity market we find that the externality is large and positive on average however the externality is negative in periods of high adverse selection we quantify the economic significance of the externality by evaluating an exchange s revenue after a fee change the internet appendix is available at https doi org 10 1287 mnsc 2016 2658 this paper was accepted by lauren cohen finance

determinants of the intrahousehold allocation of food in the rural philippines this study shows that the opportunity cost of time for husbands and wives can affect the intrahousehold distribution of food in a developing country equations which explain the relative allocation of calories within households were estimated for husbands wives and children with data for the rural philippines the estimating equation is derivable from both a joint household utility function and a bargaining model because the same households were included in the four survey rounds the various observations for a given individual were averaged for each variable in the estimation procedure wages were estimated using the heckman approach

substitution between goods and leisure in a developing country the paper explores the substitutability between goods female leisure and male leisure we find that goods and leisure are not separable we then adapt the almost ideal demand system aids to include leisure in the system in the same manner as commodities the model is not sensitive to variations in the assumption of total time available for each individual s work and leisure results from sri lanka indicate the marginal propensity to consume leisure is quite high especially in rural areas this finding has important implications for transfer programs designed to raise food consumption a somewhat surprising complementarity between male and female leisure was also observed a number of goods were found to be complements to both male and female leisure

program interventions intrahousehold distribution and the welfare of individuals modelling household behavior abstract in this essay the implications for the intrahousehold distribution of resources derived from economic models of household behavior that treat the household as maximizing a single welfare function are reviewed particular attention is paid to the within family allocation of time and food and to the effects of these resources on the schooling earnings and health status of individuals as they are affected by direct food intervention and female employment schemes and price altering policies empirical applications are provided from data sets from india indonesia and the philippines to illustrate the power and limitations of such models for illuminating household interventions and for placing restrictions on data

consolidation fragmentation and market performance this paper studies the impact of market consolidation or fragmentation on its performance examining four alternative models of exchange a consolidated clearing house fragmented clearing houses a monopoly dealer market and an interdealer market the effects of the market mechanism on the expected quantity traded the price variance faced by individual traders the quality of market price signals the expected gains from trade and the exchange implementation costs are studied

on bias correction in the multivariate sample selection model heien and wessells two step estimator for the multivariate sample selection model has been used extensively during the past 15 years a modified version of it with slightly different selectivity regressors has also appeared in the empirical literature both estimators are unfounded and generally do not correct for the sample selectivity bias as intended but have continued to gain popularity in empirical applications the properties of the modified heien wessells procedure are investigated in both the bivariate and multivariate contexts and the conditions under which this estimator fails to correct for sample selectivity are examined the theoretical properties are demonstrated with a simulated random sample

variety prices and food status in low income households the basic premise of this paper is that a household receives utility directly from the status of a food composite good which is created by combining a household s skill and creativity in preparing foods other inputs and the kinds and amounts of foods available we proceed to investigate the factors influencing the demand for and prodcution of this composite good the demand for food status in influenced most by the following characteristics race education houshold size homeownership region of household residence and income direct price effects were minor estimates of a food status production function imply that the production of food status is not much a matter of the quantities of foods consumed but rather the types of food purchased variety and the creativity of the homemaker

food security and health status in the united states food security is defined as access by all times to enough food for an active healthy life this paper explores the relationships between food security and women s self evaluated health status a theoretical model is developed which suggests that our primary interests can be served by estimating health and food security production functions we find that food security has a significant influence on a woman s self evaluated health status however the exact manifestations are difficult to quantify they may be psychological or physiolgical the most food insecure women tend to be poor and less educated tobacco use lack of physical exercise and obesity also weigh heavily good health status

market sidedness insights into motives for trade initiation we infer motives for trade initiation from market sidedness we define trading as more two sided one sided if the correlation between the number of buyer and seller initiated trades increases decreases and assess changes in sidedness relative to a control sample around events that identify trade initiators consistent with asymmetric information trading is more one sided before merger news consistent with belief heterogeneity trading is more two sided before earnings and macro announcements with greater dispersion in analyst forecasts and after news with larger announcement surprises we examine the codeterminacy of sidedness bid ask spread volatility number of trades and order imbalance

determinants of dietary quality evidence from bangladesh summary whereas a large number of studies have been devoted to analyzing consumer demand for dietary quantity much less attention has been paid to the demand for dietary quality to address this gap in the literature this paper explores the determinants of dietary quality in bangladesh using data from a nationally representative household expenditure survey conducted in 2000 we find that while male education plays a positive role female education has a substantially stronger influence further female household headship is associated with lower dietary quality than male headship thus promoting female education and addressing the unique constraints faced by female headed households with respect to diet quality could be a significant policy instrument for addressing food insecurity in bangladesh

households grocery shopping behavior in the short run theory and evidence this paper extends the study of nonmarket work activities to explain the impact of household characteristics on grocery shopping behavior a constrained utility maximization model is developed and the equilibrium conditions of the model are derived these conditions and the hypotheses implied by them relating to the determinants of time spent in a grocery shopping trip the size of a purchase and the number of such trips within a given period of time were tested using data from a sample which identified the household characteristics of grocery shoppers in these tests using two stage least squares the theoretical implications of our simultaneous equations model are significantly supported

a demand systems analysis of food commodities by u s households segmented by income using the 1987 88 nationwide food consumption survey twelve food commodity groups were analyzed according to household poverty status parameter estimates were used to obtain subsistence expenditures own price elasticities expenditure elasticities and income elasticities own price elasticities were similar between the income groups for most commodities however income elasticities were consistently higher for the lower income group the use of average estimates of price and income elasticities for the population as a whole for the projection of individual commodity demands is not likely to be successful if notable changes are evident in income distribution

mixed bundling in two sided markets in the presence of installed base effects we analyze mixed bundling in two sided markets where installed base effects are present and find that the pricing structure deviates from traditional bundling as well as the standard two sided markets literature we determine prices on both sides fall with bundling mixed bundling acts as a price discrimination tool segmenting the market more efficiently consequently as a by product of this price discrimination the two sides are better coordinated and social welfare is enhanced we show unambiguously that platform participations increase on both sides of the market after theoretically evaluating the impact mixed bundling has on prices and welfare we take the model predictions to data from the portable video game console market we find empirical support for all theoretical predictions this paper was accepted by j miguel villas boas marketing

nutrient consumption and household income in rural mexico we estimate the income elasticity for a variety of macro and micronutrients using a sample of poor rural households in mexico the nutrientincome elasticity is estimated using both parametric and semiparametric methods a special focus is placed on the nonlinearity of the relationship between nutrient intake and income and on measurement error and endogeneity issues one major finding is that income elasticity for calories is close to zero when we control for measurement error issues for some nutrients namely fats vitamin a and c calcium and heme iron we find a sizeable positive income elasticity robust to the choice of the estimator and percentiles at which it is evaluated these nutrients are also those for which we find the largest deficiency in our sample in addition we find that for the poorest households in our sample the deficiency of total energy protein and zinc is not accompanied by a positive income elasticity

hierarchic demand and the engel curve for variety ahstract the usual treatment of consumer demand theory assumes a solution to the demand equations with positive quantities of all commodities this paper characterises a class called hierarchic demand systems for which only a subset of commodities are in the purchased set the hierarchic linear expenditure svstem is used to illustrate interesting properties of such systems the empirical section shows how the number of commodities purchased expands with total expenditure both in aggregate and for commodity groups the data clearly establish the empirical importance of corner solutions and of the purchase decision in demand studies

eighths sixteenths and market depth changes in tick size and liquidity provision on the nyse using limit order data provided by the nyse we investigate the impact of reducing the minimum tick size on the liquidity of the market while both spreads and depths quoted and on the limit order book declined after the nyse s change from eighths to sixteenths depth declined throughout the entire limit order book as well the combined e ect of smaller spreads and reduced cumulative limit order book depth has made liquidity demanders trading small orders better o however traders who submitted

evaluating food plans and poverty thresholds 1987 evaluating food plans and poverty thresholds applied economics vol 19 no 10 pp 1341 1352

price discrimination in the context of vertical differentiation an application to canadian wheat exports this study examines the ability of the canadian wheat board cwb to price discriminate in bread wheat exports this study models wheat as a vertically differentiated intermediate good and modifies the model of vertical differentiation by mussa and rosen to the realities of wheat import demand the conceptual model isolates the bases of price discrimination and demonstrates that the cwb s ability to exploit cost differences in pricing depends on the extent of the differentiation between canadian and u s wheat this model is implemented using monthly confidential price data provided by the cwb for exports to japan the united kingdom and two markets aggregating remaining exports through canada s west and east coasts for 1982 1994 the data indicate that the cwb charges different prices to different countries for wheat of the same grade and protein content results from the model indicate that the price difference between any two markets is not completely explained by elements of perfect competition however the evidence is mixed regarding the ability of the cwb to utilize all the instruments available to price discriminate thus the cwb s pricing strategy may be more complex and dynamic than the prescription for static producer surplus maximization derived in this study

demographic variables in demand analysis in this paper the authors discuss five procedures for incorporating demographic variables into theoretically plausible demand systems translating scaling and the gorman reverse gorman and implicit prais houthakker procedures these five procedures are used to incorporate a single demographic variable the number of children in a household into the generalized ces demand system using household budget data for the united kingdom for the period 1966 1972 excerpt

economies of scale and market structure in international grain trade a large body of literature has examined international grain trade in imperfectly competitive models the article develops a two stage duopoly model that considers a private trader and a state trading enterprise ste competing on a foreign market the key difference between the private trader and the ste is their international organization while the ste makes use of external agents to export the private firm may choose to internalize international transactions the game is solved for different modes of competition and under both assumptions of homogeneous and differentiated products in order to assess how these assumptions affect the outcome of the game the results of the game are examined by using numerical examples the analysis shows that external shocks on export markets may result in a change of market structure and consequently of market shares these effects depend on the initial market structure furthermore the degree of product differentiation and the assumed mode of competition significantly affect the relative values of transaction and fixed costs at which the market structure changes

does religion matter to informal finance evidence from trade credit in china informal finance plays an important role in transitional economies with weak legal institutions such as china as a major informal finance instrument trade credit relies on informal institutions

market behavior in a clearing house one of the most fundamental market mechanisms is the clearing house where orders are accumulated over time and the market is cleared periodically the issue addressed in this study is the statistical behavior of the market under this neutral mechanism in the framework of a tractable stochastic model which captures the underlying uncertainties and indivisibilities in the demand and supply schedules applying renewal theory we derive closed form results for the behavior of prices and quantities and pursue the implications of the possibility of no trade and the multiplicity of market clearing prices

can drought increase total calorie availability the impact of drought on food consumption and the mitigating effects of a conditional cash transfer program abstract this study uses the panel data of a randomized experiment from the mexican progresa program to evaluate the impact of drought on total calorie availability and the mitigating effects of progresa on food consumption in periods of drought drought reduced total expenditures and total food expenditures but increased the total availability of calories this paradox can be explained by the impact of drought on the composition of calories that is it reduced the consumption of expensive calories in such foods as vegetables fruits and animal products but increased calories consumed from cheaper sources such as grains this study finds that progresa can completely mitigate the negative effects of drought on calorie availability from vegetables fruits and other sources however progresa cannot mitigate the impact of drought on calories available from grains the analysis also shows that during drought households who increase their consumption of grains get them mainly from purchased sources rathe

market microstructure and securities values evidence from the tel aviv stock exchange abstract this paper examines the value effects of improvements in the trading mechanism selected stocks on the tel aviv stock exchange were transferred gradually from a daily call auction to a mechanism where the call auction was followed by iterated continuous trading sessions this event was associated with a positive and permanent price appreciation the cumulative average market adjusted return over a period that started five days prior to the announcement and ended 30 days after the stocks started trading by the new method was approximately 5 5 in addition we find positive liquidity externalities spillovers across related stocks and improvements in the value discovery process due to the improved trading method finally there was a positive association between liquidity gains and price appreciation

will developing country nutrition improve with income a case study for rural south india aggregate estimates of food expenditure are consistent with such a possibility implying income expenditure elasticities close to one however the high degree of aggregation at which such estimates are made means that the considerable increase in price per nutrient as income increases is ignored and the nutrient elasticities are therefore overstated estimates for a rural south indian sample indicate that this bias is considerable and that the true nutrient elasticities with respect to income may be close to zero

determinants of food consumption in rural sierra leone abstract this paper reports the application of a quadratic expenditure system with demographic variables to the household consumption leisure choice component of a household firm model a system of seven commodities is estimated including five foods non food and leisure appropriate for such a level of disaggregation a demand system is used the quadratic expenditure system which allows for a flexible relationship between full income and commodity expenditures without sacrificing parsimony in parameters demographic data on households are explicitly incorporated into the model allowing for a richer specification than can be achieved by using per capita variables the data are from a cross section survey of households in rural sierra leone price variation exists by region permitting estimation of a complete demand system engel curves are found to be significantly non linear with marginal expenditure on rice the major staple declining with higher income most foods are found to be reasonably price responsive with sizeable own price substitution effects declining with higher income aggregate labor supply is found to be price inelastic

trading fees and efficiency in limit order markets competition among trading platforms has considerably reduced trading fees in stock markets we show that this evolution is not necessarily beneficial to investors although they increase gains from trade when a trade happens lower trading costs can induce investors to post limit orders with a smaller execution probability in this case gains from trade are realized less frequently and investors can be worse off our model has testable implications for the effects of trading fees and their breakdown between liquidity suppliers and liquidity demanders on limit order fill rates and bid ask spreads

do liquidity measures measure liquidity abstract given the key role of liquidity in finance research identifying high quality proxies based on daily as opposed to intraday data would permit liquidity to be studied over relatively long timeframes and across many countries using new measures and widely employed measures in the literature we run horseraces of annual and monthly estimates of each measure against liquidity benchmarks our benchmarks are effective spread realized spread and price impact based on both trade and quote taq and rule 605 data we find that the new effective realized spread measures win the majority of horseraces while the amihud 2002 illiquidity and stock returns cross section and time series effects journal of financial markets 5 31 56 measure does well measuring price impact

island goes dark transparency fragmentation and regulation responding to a september 2002 regulatory enforcement the island electronic communications network stopped displaying its limit order book in the three most active exchange traded funds etfs where it was the dominant venue island s share of trading activity and price discovery fell fragmenting the market etf prices adjust more slowly when island goes dark and there is substantial price discovery movement from etfs to the futures market trading costs increase on island and decrease off island with higher trading costs overall when island later redisplays its orders market quality improves with transparency and the reduction in fragmentation both playing important roles copyright 2005 oxford university press

market structure determinants of national brand private label price differences of manufactured food products reply this paper estimates the relationships between market structure and the lerner index of monopoly constructed from price data on processed food products sold through grocery stores a theoretical model of a differentiated oligopoly specifies two determinants of price cost margins the herfindahl hirschman index of seller concentration adjusted for the elasticity of demand and the industry advertising to sales ratio the results indicate that the three principal determinants of price cost margin variation in order of their impacts are advertising intensity elasticity of demand and concentration previous structure performance studies that did not incorporate the elasticity of demand were probably misspecified

competing at home to win abroad evidence from japanese industry the study explores the influence of domestic competition on international trade performance using data from a broad sample of japanese industries domestic rivalry is measured directly using market share instability rather than employing structural variables such as seller concentration we find robust evidence that domestic rivalry has a positive and significant relationship with trade performance measured by world export share particularly when r d intensity reveals opportunities for dynamic improvement and innovation conversely trade protection reduces export performance these findings support the view that local competition not monopoly collusion or a sheltered home market pressures dynamic improvement that leads to international competitiveness

demand for nutrients in india 1993 to 2004 in response to the deaton and dreze 2009 explanation of a downward shift in the calorie engel curve in terms of lower requirements due to health improvements and lower activity levels in india we develop an alternative explanation embedded in a standard demand theory framework with food prices and expenditure as a proxy for income cast in a pivotal role we find robust food price and expenditure effects and shifting food price elasticities there are shifts in demands due to factors other than lower requirements so while the deaton and dreze 2009 explanation is not rejected it is arguable that it is complementary to the demand based explanations

liquidity resiliency and market quality around predictable trades theory and evidence abstract we extend the theory of strategic trading around a predictable liquidation by considering the role of market resiliency our model predicts that even a monopolist strategic trader improves market quality and increases liquidator proceeds if trades temporary price impacts are quickly reversed and that competition among strategic traders strictly improves market quality we provide related empirical evidence by studying prices liquidity and individual account trading activity around the large and predictable roll trades undertaken by a large exchange traded fund etf the evidence indicates narrower bid ask spreads greater order book depth and improved resiliency on roll dates we find that a larger number of individual trading accounts provide liquidity on roll dates and do not find evidence of the systematic use of predatory strategies on balance the theory and evidence imply that traders supply liquidity to rather than exploit predictable trades in resilient markets

two sided markets a progress report the paper provides a road map to the burgeoning literature on two sided markets and presents new results it identifies two sided markets with markets in which the structure and not only the level of prices charged by platforms matters the failure of the coase theorem is necessary but not sufficient for two sidedness the paper builds a model integrating usage and membership externalities that unifies two hitherto disparate strands of the literature emphasizing either form of externality and obtains new results on the mix of membership and usage charges when price setting or bargaining determine payments between end users

impacts of capital and land constraints on the economics of new livestock technology in western kenya abstract the introduction of new forages and milk marketing improvements was projected to permit even the smallest modeled farms in a western kenya region to adopt dual purpose goats and thereby improve family income and nutrition expanded credit permitted modeled medium and large farms especially to vigorously exploit these innovations credit also expanded income more than did goat management improvements because credit extension assistance marketing improvements and new forages will leave projected incomes of small farmers below those of medium and large farmers in the study region development of off farm jobs may still be necessary to supplement the incomes of this fast growing group the marginal value of capital for medium and large farmers with new livestock technology was high this suggests that government subsidized credit might be unnecessary with proper infrastructural and legal support private capital markets might develop as new livestock technology and marketing improvements expand the demand for borrowing

managing global sourcing inventory performance the use of global suppliers has increased considerably over the last three decades operations management theory establishes that global sourcing requires more units of inventory but since these units are often procured at a lower cost from global suppliers the capital invested in inventory and the consequent financial burden may increase or decrease with global sourcing this study provides rigorous firm level empirical evidence that links the global sourcing practices of public u s firms and their inventory investments we process bill of lading manifests customs forms to extract information on over half a million sea shipments from global suppliers to u s public firms and link this information with quarterly financial data from the compustat database we provide stylized facts on the participation of different firms and sectors in global trade using a simultaneous equation model we find that an increase in global sourcing results in an increase in inventory investment a 10 shift in sourcing from domestic to global suppliers increases the inventory investment by 8 8 for an average firm in our sample we also find that increasing the number of suppliers can mitigate this increase in inventory investment for example going from single to dual sourcing reduces inventory investment by about 11 we illustrate the use of our estimates to identify the impact of changing global sourcing strategy on inventory investment and operational performance metrics this paper was accepted by martin lariviere operations management

two sided network effects a theory of information product design how can firms profitably give away free products this paper provides a novel answer and articulates trade offs in a space of information product design we introduce a formal model of two sided network externalities based in textbook economics a mix of katz and shapiro network effects price discrimination and product differentiation externality based complements however exploit a different mechanism than either tying or lock in even as they help to explain many recent strategies such as those of firms selling operating systems internet browsers games music and video the model presented here argues for three simple but useful results first even in the absence of competition a firm can rationally invest in a product it intends to give away into perpetuity second we identify distinct markets for content providers and end consumers and show that either can be a candidate for a free good third product coupling across markets can increase consumer welfare even as it increases firm profits the model also generates testable hypotheses on the size and direction of network effects while offering insights to regulators seeking to apply antitrust law to network markets

information endogeneity and consumer health behaviour application to dietary intakes due to heightened public health interest a growing number of consumer health behaviour studies are focusing on the effect of health information on the demand for health inputs and outcomes many of these studies however have overlooked the potential endogeneity of information variables stemming from unobserved individual heterogeneity due to simultaneity bias ignoring endogeneity may lead to inaccurate estimates of informational effects on health behaviour using dietary intake data for fat saturated fat cholesterol and fibre this paper illustrates the pitfalls of treating health information related to these nutrients as exogenous variables in their demand equations in most of the estimated models the exogeneity of information is statistically rejected when the information variables are treated as exogenous variables their effects on dietary intakes are underestimated the estimated effects of key intake determinants such as income education ethnicity and race are also different in such a

better late than nothing some comments on deaton 2009 and heckman and urzua 2009 two recent papers deaton 2009 and heckman and urzua 2009 argue against what they see as an excessive and inappropriate use of experimental and quasi experimental methods in empirical work in economics in the last decade they specifically question the increased use of instrumental variables and natural experiments in labor economics and of randomized experiments in development economics in these comments i will make the case that this move towards shoring up the internal validity of estimates and towards clarifying the description of the population these estimates are relevant for has been important and beneficial in increasing the credibility of empirical work in economics i also address some other concerns raised by the deaton and heckman urzua papers

estimating a household production function heterogeneity the demand for health inputs and their effects on birth weight the household production literature emphasizes that technical or biological processes condition input selection by households in their production activities along with prices and income exogenous variations in health to the extent that they are perceived by individuals heterogeneity lead to correlations between inputs and health outcomes that cannot be used to derive causal conclusions therefore estimates of health technology must be obtained from a behavioral model in which health inputs are themselves choices consistent estimates are reported of the effect of endogenous inputs such as medical care smoking and fertility on birth weight and fetal growth in the presence of health heterogeneity

liquidity externalities and adverse selection evidence from trading after hours this paper examines liquidity externalities by analyzing trading costs after hours there is less than 1 20 as many trades per unit time after hours as during the trading day the reduced trading activity results in substantially higher trading costs quoted and effective spreads are three to four times larger than during the trading day the higher spreads reflect greater adverse selection and order persistence but not higher dealer profits because liquidity provision remains competitive after hours the greater adverse selection and higher trading costs provide a direct measure of the magnitude of the liquidity externalities generated during the trading day understanding network effects and liquidity externalities is one of the most important outstanding issues in market design madhavan 2000 and market regulation macey and o hara 1999 liquidity externalities arise from bringing traders together in space and time to reduce search and trading costs bringing traders together creates liquidity externalities because the additional traders arriving in the marketplace reduce trading costs for all investors to date attention has focused almost exclusively on spatial network effects by examining the trading of securities in different markets at the same time lee 1993 hasbrouck 1995 and others in contrast this paper studies the effects of temporal consolidation of trades by analyzing trading during and outside of exchange trading hours a well known liquidity externality arises from asymmetric information rational informed traders break up their orders across markets and over time this provides incentives for liquidity traders to consolidate their trades geographically garbade and silber 1979 mendelson 1982 1987 pagano 1989a 1989b and intertemporally admati and pfleiderer 1988 and foster and viswanathan 1990 it has been difficult to document the importance of these liquidity externalities however unless there are barriers that restrict the flow of orders from one trading venue to another in equilibrium contemporaneous

liquidity and the law of one price the case of the futures cash basis deviations from no arbitrage relations should be related to market liquidity because liquidity facilitates arbitrage at the same time a wide futures cash basis may trigger arbitrage trades and in turn affect liquidity we test these ideas by studying the dynamic relation between stock market liquidity and the index futures basis there is evidence of two way granger causality between the short term absolute basis and liquidity and liquidity granger causes longer term absolute bases shocks to the absolute basis predict future stock market liquidity the evidence suggests that liquidity enhances the efficiency of the futures cash pricing system copyright 2007 by the american finance association

the intrahousehold demand for nutrients in rural south india individual estimates fixed effects and permanent income good estimates of nutrient intake responses to prices and income are very useful for the evaluation of the numerous efforts to improve nutrition in many developing countries through pricesubsidy and income generation policies we discuss three problems in standard estimates of these responses and then illustrate their implications for nutrient demand relations for a poor sample from rural south india 1 intra household nutrient allocations usually are ignored in this case nutrient intakes for females systematically have algebraically lower price elasticities than do those for males which may leave the females particularly vulnerable at times of food shortages 2 unobserved fixed effects may bias the estimates of responses to observed variables in this case not only the community fixed effects on which the previous literature has focused but also household and individual fixed effects are important failure to control for them results in substantial algebraically upward biases in many estimated price responses 3 most previous studies use current instead of permanent income which a priori may account for the low estimated income elasticities in this case however the use of permanent income does not change the conclusion that the nutrient intakes responses to income are quite small

further evidence on competition in the us grain export trade this study analyzes the relationship between export market structure and the pricing behavior of u s grain exporting firms a generalized cournot model is estimated by two stage least squares using pooled data sets for u s wheat and corn exports the cross sectional units correspond to foreign country destinations discriminatory export pricing behavior was found to be significantly related to export seller concentration u s market share total export volume and import market size yet the estimated coefficients linking these market structure variables to the export price markup were relatively small in magnitude suggesting little quantitative impact from market power copyright 1994 by blackwell publishing ltd

keyword search advertising and first page bid estimates a strategic analysis in using the generalized second price gsp auction to sell advertising slots a search engine faces several challenges advertisers do not truthfully bid their valuations and the valuations are uncertain furthermore advertisers are budget constrained in this paper we analyze a stylized model of the first page bid estimate fpbe mechanism first developed by google and demonstrate its advantages in dealing with these challenges we show why and when the fpbe mechanism yields higher profits for the search engine compared with the traditional gsp auction and the gsp auction with advertiser specific minimum bid in the event that a high valuation advertiser is budget constrained the search engine can use the fpbe mechanism to alter the listing order with the intent of keeping the high valuation advertiser in the auction for a longer time the resulting increase in the search engine s profits is not necessarily at the expense of the advertisers because the combined profits of the advertisers and the search engine increase this paper was accepted by j miguel villas boas marketing

prices infrastructure household characteristics and child height household survey data from brazil matched with information collected at the municipio county level are used to examine the relation between parental characteristics primarily education community infrastructure and services and child height data are drawn from 2 sources informacoes basicas municipais 1974 is a periodic survey of 4000 municipios on infrastructure health and education services estudo nacional da despesa familiar 1974 75 is a household survey covering 37000 children under age 8 on income expenditure anthropometry and socio demographic characteristics local food price indices were derived from these data child height is significantly affected by local infrastructure particularly modern sewerage and piped water in urban areas and electricity in rural settings these effects are stronger for children over 2 those of better educated mothers and those in households spending more higher prices for dairy products and sugar are linked to lower urban child height and higher fish prices to lower rural child height significantly for children of illiterate mothers higher prices for meat and rice are associated with taller height possible because men usually eat these foods mothers with elementary schooling can counteract the effects of food prices on child height number of teachers is positively related to height in rural children numbers of nurses and of hospital beds is associated with shorter children suggesting that large hospitals locate in poor urban areas this study has succeeded in identifying some public investments that affect child health

more evidence on nutrition demand income seems overrated and women s schooling underemphasized abstract malnutrition is widespread in the developing world controversy continues concerning the roles of income household size and women s schooling on nutrient demand empirical estimates for nicaragua suggest that income elasticities are small and inversely associated with income levels there are some economies of scale in household size the elasticity for women s schooling is higher than those for income or household size and women s backgrounds are important the results cast doubt on the strong emphasis the world bank and others have placed on income and suggest that schooling may be working through tastes not only through productivity

towards a theory of famine relief policy abstract this paper examines how famine mortality is related to the distribution of food consumption a theoretical model is proposed of how individual survival chances are affected by changes in consumption uncertainty in survival prospects arises from the errors made by any observer in assessing health at given current consumption the theory is used to explore two policy issues in famine relief the choice of budgetary rules for allocating emergency aid and the case for price stabilization policies during famines applications to data for two famines in south asia suggest that successful price stabilization would have had substantial benefits in reducing mortality

random competitive exchange price distributions and gains from trade abstract this paper studies the behavior of a competitive exchange under uncertain preferences and random indivisible endowments we obtain explicit closed form results for the price distribution and expected gains from trade both for case where the market is thin and the number of traders is low and for the asymptotic case where the number of traders tends to infinity we demonstrate that increasing the number of traders reduces price variability and increases the expected gains from trade and that increasing the variability of traders reservation prices increases price variability as well as the expected asymptotic gains from trade