the optimal indexation of asymmetric information contracts the indexation of labour contracts is examined in a setting from which the hedging motive for partial indexation has been excluded since firms have better information than workers contracts must satisfy an incentive compatibility constraint the optimal degree of indexation depends on the incentives generated by the best fully indexed contract if firms would understate overstate the productivity of labour under this contract the optimal contract is partially more than fully indexed l indexation optimale des contrats quand l information est asymetrique l auteur examine l indexation de contrats de travail dans un monde dont on a elimine l indexation partielle dans le simple but de se couvrir comme les firmes ont une meilleure information que les travailleurs les contrats doivent satisfaire une contrainte de compatibilite le degre optimal d indexation depend des incitations engendrees par le meilleur contrat pleinement indexe si les firmes sous evaluent sur evaluent la productivte des travailleurs dans le contrat le contrat optimal est partiellement plus que pleinement indexe

involuntary unemployment and implicit contracts this paper provides an explanation of involuntary umemployment arising as a consequence of asymmetric information between firms and workers involuntary unemployment is defined as a situation where ex post gains to trade exist a model of labor contracts is developed where the allocations are not ex post optimal it is shown that inferiority of leisure is a necessary and sufficient condition for the existence of involuntary unemployment

strategic labour contracts labor contracts affect a firm s cost function and for this reason they can be used as a recommitment device to gain a strategic advantage against other firms in a model that is otherwise neutral it is found that if firms compete in prices then strategic considerations alone yield results similar to those obtained by c azariadis 1983 workers are underemployed and worse off in more adverse states of nature on the other hand if firms compete in quantities then the equilibrium contracts resemble those of j green and c kahn 1983 workers are overemployed and better off in more adverse states

implicit contracts moral hazard and unemployment this paper considers a firm whose marginal revenue product of labor is a random variable we derive the form of an optimal long term contract between workers and the firm under the assumption that labor s marginal product is observed by the firm but not by the workers we show that the existence of asymmetric information causes unemployment to be greater than in a situation where information about labor s marginal product is public or where employment is determined in spot markets in particular unemployment can occur when the marginal product of labor exceeds the reservation wage

a factor analytic probit model for representing the market structure in panel data internal market structure analysis infers both brand attributes and consumer preferences for those attributes from preference or choice data the authors exploit a new method for estimating probit models from panel data to infer market structures that can be displayed in few dimensions even though the model can represent every possible vector of purchase probabilities

asymmetric information multiperiod labor contracts and inefficient job separations economists have for some time been telling the world and each other that in a dynamic economy some labor turnover is to be expected and is in fact efficient however there is a pervasive feeling that not all of the observed turnover is efficient the dilemma of course is to provide satisfactory reasons why inefficient turnover should occur with optimizing rational economic agents in light of this problem recent developments in implicit contract theory 1 4 5 have begun to focus on the idea that in a world of uncertainty asymmetric information and moral hazard problems may prevent efficient fully enforceable contingent claims contracts from developing in particular the asymmetric information i e firms privately observe their profits and workers privately observe their alternatives and moral hazard problems make efficient turnover unlikely because parties making separation decisions have neither all available relevant information nor have an incentive to use this information to make an efficient decision while this investigation into the ramifications of asymmetric information has yielded new insights analysis in previous studies has been limited to models in which separations occur only in the final period of the model in this paper a simple multiperiod model is developed in which separations may occur in each of several successive periods the multiperiod specification enables us to distinguish between temporary and permanent separations and to focus attention on the potential for inefficient separations induced by asymmetric information problems in an intertemporal setting in an intertemporal model in which separations may occur in any one of several successive periods intertemporal allocation problems arise because compensation in a given period plays an allocative role not only in that particular period but also in all periods prior to that period that the terms of compensation may play a multiple intertemporal role in allocating labor has been recognized previously in other contexts for instance this argument has been used to explain the observed occurrence of rising wage profiles with tenure in the presence of such factors as worker shirking or firm specific skill acquisition 2 9 in this asymmetric information setting intertemporal allocation problems

endogeneity in brand choice models applications of random utility models to scanner data have been widely presented in marketing for the last 20 years one particular problem with these applications is that they have ignored possible correlations between the independent variables in the deterministic component of utility price promotion etc and the stochastic component or error term in fact marketing mix variables such as price not only affect brand purchasing probabilities but are themselves endogenously set by marketing managers this work tests whether these endogeneity problems are important enough to warrant consideration when estimating random utility models with scanner panel data our results show that not accounting for endogeneity may result in a substantial bias in the parameter estimates

invited paper even the rich can make themselves poor a critical examination of iv methods in marketing applications marketing is a field that is rich in data our data is of high quality often at a highly disaggregate level and there is considerable variation in the key variables for which estimates of effects on outcomes such as sales and profits are desired the recognition that in some general sense marketing variables are set by firms on the basis of information not always observable by the researcher has led to concerns regarding endogeneity and widespread pressure to implement instrumental variables methods in marketing problems the instruments used in our empirical literature are rarely valid and the iv methods used can have poor sampling properties including substantial finite sample bias and large sampling errors given the problems with iv methods a convincing argument must be made that there is a first order endogeneity problem and that we have strong and valid instruments before these methods should be used if strong and valid instruments are not available then researchers need to look toward supplementing the information available to them for example if there are concerns about unobservable advertising or promotional variables then the researcher is much better off measuring these variables rather than using instruments such as lagged marketing variables that are clearly invalid ultimately only randomized variation in marketing variables with proper implementation and large samples can be argued to be a valid instrument without further assumptions

a regime switching model of cyclical category buying in many categories consumers display cyclical buying they repeatedly purchase in the category for several periods followed by several periods of not buying we believe that the cyclicality is a manifestation of cross category substitution by the consumer caused by variety seeking tendencies as well as by the firm s marketing activities in all relevant categories we propose a markov regime switching random coefficient logit model to represent these behaviors as stochastic switching between high and low category purchase tendencies the main feature of the proposed model is that it divides the stream of purchase decisions of a consumer into distinct regimes with different parameter values that characterize high versus low purchase tendencies in an empirical application of the model to purchases of yogurt buying households we find that as many as 38 3 households display cyclicality between high and low yogurt purchasing tendencies predictions from our proposed model track observed yogurt purchases of households over time closely and the model also fits better than two benchmark models alternating between high and low purchase tendencies may correspond with changing levels of consumer inventory in a substitute category if one ignores this phenomenon a correlation between yogurt inventory and the error term in utility arises leading to biased estimates also we show that cyclicality in buying has a key implication for a firm s price promotion strategies a price reduction that is offered to a household during its high purchasing tendency period will result in greater increases in sales than one that is offered during its low purchasing period this opens up a new dimension for enhancing the effectiveness of promotions customized timing of price reductions

a bayesian semiparametric approach for endogeneity and heterogeneity in choice models marketing variables that are included in consumer discrete choice models are often endogenous extant treatments using likelihood based estimators impose parametric distributional assumptions such as normality on the source of endogeneity these assumptions are restrictive because misspecified distributions have an impact on parameter estimates and associated elasticities the normality assumption for endogeneity can be inconsistent with some marginal cost specifications given a price setting process although they are consistent with other specifications in this paper we propose a heterogeneous bayesian semiparametric approach for modeling choice endogeneity that offers a flexible and robust alternative to parametric methods specifically we construct centered dirichlet process mixtures cdpm to allow uncertainty over the distribution of endogeneity errors in a similar vein we also model consumer preference heterogeneity nonparametrically via a cdpm results on simulated data show that incorrect distributional assumptions can lead to poor recovery of model parameters and price elasticities whereas the proposed semiparametric model is able to robustly recover the true parameters in an efficient fashion in addition the cdpm offers the benefits of automatically inferring the number of mixture components that are appropriate for a given data set and is able to reconstruct the shape of the underlying distributions for endogeneity and heterogeneity errors we apply our approach to two scanner panel data sets model comparison statistics indicate the superiority of the semiparametric specification and the results show that parameter and elasticity estimates are sensitive to the choice of distributional forms moreover the cdpm specification yields evidence of multimodality skewness and outlying observations in these real data sets data as supplemental material are available at http dx doi org 10 1287 mnsc 2013 1811 this paper was accepted by j miguel villas boas marketing

patient or physician oriented marketing what drives primary demand for prescription drugs abstract the authors analyze primary demand effects of marketing efforts directed at the physician detailing and professional journal advertising versus marketing efforts directed at the patient direct to consumer advertising the analysis covers 86 categories or approximately 85 of the u s pharmaceutical market during the 2001 2005 period primary demand effects are rather small in contrast with the estimated sales effects for individual brands by using a new brand level method to estimate primary demand effects with aggregate data the authors show that the small effects are due to intense competitive interactions during the observation period but not necessarily to low primary demand responsiveness in contrast with previous studies the authors also find that detailing is more effective in driving primary demand than direct to consumer advertising a category sales model cannot provide such insights in addition a category sales model likely produces biased predictions about period by perio

search and consumer theory a consumer faces list prices for commodities but can buy one at a discount discounts vary randomly between sellers the number of quotations sought depends on list prices search costs and wealth this function is homogeneous of degree zero and provided some sufficient conditions are satisfied is increasing in wealth decreasing in search cost independent of the list price of the discounted commodity if indirect utility is multiplicatively separable increasing in the list price if the commodity is a necessity increasing in the list price of substitutes slutsky s equation is generalized to include search

addressing endogeneity in aggregate logit models with time varying parameters for optimal retail pricing abstract it is well known that price endogeneity is a severe problem in demand models for market level data e g aggregate logit models because it leads to biased estimates and therefore incorrect managerial implications if the price parameter varies over time as is usually the case the relevance of the issue increases because standard methods to correct endogeneity biases e g generalized method of moments fail this paper presents a control function approach as a remedy a comprehensive simulation study demonstrates this method s suitability such that addressing endogeneity with the control function approach is the best choice moreover addressing the endogeneity problem incorrectly may be even more harmful than simply ignoring it to further illustrate the control function approach we analyze the demand for canned tuna using aggregate retailer level data here all utility parameters vary over time and price endogeneity is indeed an issue effectively addressing price endogeneity correct has positive economic consequences a normative model analysis reveals that implementing the control function approach yields a 3 increase in retailer profits

demand function estimation and the law of one price this paper shows that the method of estimating of demand functions may contain an erroneous implicit assumption when aggregated data are used this assumption revealed by the choice of regressors yields estimates of own price elasticity and other coefficients that are inconsistent it can also cause heteroscedasticity in the second stage of two stage least squares estimation where none would otherwise exist

aggregate impact of different brand development strategies current branding literature investigates the spillover effects and extension effects due to the introduction of product extensions however no study so far has evaluated the aggregate market impact of these effects across different brand development strategies or accounted for the strategic decision to introduce the extension it is important to examine the above given the significant investments and the high failure rates associated with the introduction of new product extensions in this study we develop an analytical framework that derives revenue outcome due to an extension introduction as a function of spillover and extension effects we empirically estimate the above effects through a bayesian endogenous switching model that jointly models market shares of the extension and its parent brand along with the strategic decision to introduce the extension and the endogeneity in prices by using a data set that covers 155 extensions introduced across 20 u s geographic markets we obtain several new gen

estimating a stockkeeping unit level brand choice model that combines household panel data and store data abstract the marketing literature has addressed the issues of heterogeneity and endogeneity when estimating a choice model with household level panel data when using these data at the stockkeeping unit or the universal product code level choices for each item in each of the time periods under consideration cannot be observed without such information it is difficult to control for item and time period specific unmeasured characteristics because there is no information on alternatives during those periods in which they are not purchased by any of the panelists in general when a product category has many alternatives each with fairly small shares the household sample may not contain sufficient choices for each alternative thus negatively affecting the ability to control for endogeneity with household data in contrast because aggregate store level data for those stores in which the panel makes purchases are the aggregation of purchases by all households visiting the stores the data contain the

modeling consumer demand for variety consumers are often observed to purchase more than one variety of a product on a given shopping trip the simultaneous demand for varieties is observed not only for packaged goods such as yogurt or soft drinks but in many other product categories such as movies music compact disks and apparel multinomial mn choice models cannot be applied to data exhibiting the simultaneous choice of more than one variety the random utility interpretation of either the mn logit or probit model uses a linear utility specification that cannot accommodate interior solutions with more than one variety alternative chosen to analyze data with multiple varieties chosen requires a nonstandard utility specification standard demand models in the economics literature exhibit only interior solutions we propose a demand model based on a translated additive utility structure the model nests the linear utility structure while allowing for the possibility of a mixture of corner and interior solutions where more than one but not all varieties are selected we use a random utility specification in which the unobservable portion of marginal utility follows a log normal distribution the distribution of quantity demanded the basis of the likelihood function is derived from these log normal random utility errors the likelihood function for this class of models with mixtures of corner and interior solutions is a mixed distribution with both a continuous density portion and probability mass points for the corners the probability mass points must be calculated by integrals of the log normal errors over rectangular regions we evaluate these high dimensional integrals using the ghk approximation we employ a bayesian hierarchical model allowing household specific utility parameters our utility specification related to the approach of wales and woodland 1983 who employ a translated quadratic utility function wales and woodland were only able to study at the most three varieties because there was no practical way to evaluate the utility function at that time in addition the quadratic utility specification is not a globally valid utility function making welfare computations and policy experiments questionable hendel 1999 and dube 1999 present an alternative approach in the utility function which is constructed by summing up over unobservable consumption occasions while only one variety is consumed on each occasion the marginal utilities of varieties change over the consumption occasions giving rise to a simultaneous purchase of multiple varieties our bayesian inference approach allows us to obtain individual household estimates of utility parameters household utility estimates are used to compute the value of each variety we compute a compensating value for the removal of each flavor that is we compute the monetary equivalent of the household s loss in utility from removal of a flavor these calculations show that households highly value popular flavors and would incur substantial utility losses from removal of these flavors from the yogurt assortment next we consider the implications of our model for retailer assortment and pricing policies given limited shelf space only a subset of the possible varieties can be displayed for purchase at any one time if consumers value variety then a retailer with lower variety must compensate the consumers in some way such as a lower price level we see this trade off between price and variety across different retailing formats discount or warehouse format retailers often have both lower variety and lower prices to measure this trade off we explore the utility loss from reduction in variety and find the reductions in price that will compensate for this utility loss these price reduction calculations must be based on a valid utility structure heterogeneity in tastes is critical in these utility computations and policy experiments we find that a relatively small fraction of households with extreme preferences dominate the compensating value computations that is some households are observed to purchase mostly or exclusively one variety these households must be heavily compensated for the removal of this variety from the assortment in some retailing contexts customization of the assortment is possible at the customer level we show that such customization virtually eliminates any utility loss from reduction in variety

renegotiation and information revelation over time the case of optimal labor contracts the paper analyzes the issue of commitment in grossman and hart s model of optimal labor contracts under asymmetric information about firm profitability we extend their framework by allowing employment to vary over time at equidistant intervals when both parties can precommit ex ante not to renegotiate the contract this replicates the grossman hart outcome each subperiod when precommitment is not possible information revealed through the contract can create pareto improving renegotiation opportunities and the issue of optimal information revelation arises the paper analyzes the impact of ex post pareto improving renegotiations on the optimal contract

optimal labour contracts under asymmetric information an introduction the review of economic studies has instituted a new series of lectures to be given annually by a younger british economist at the association of university teachers of economics meetings the choice of lecturer is determined by a panel whose members are currently professors hahn mirrlees and nobay this paper is a revised version of the first lecture in the series it was presented at the aute meeting held at the university of surrey in april 1982 and was refereed in the usual way mak

competitive price discrimination strategies in a vertical channel using aggregate retail data we explore opportunities for targeted pricing for a retailer that only tracks weekly store level aggregate sales and marketing mix information we show that it is possible using these data to recover essential features of the underlying distribution of consumer willingness to pay knowledge of this distribution may enable the retailer to generate additional profits from targeting by using choice information at the checkout counter in estimating demand we incorporate a supply side model of the distribution channel that captures important features of competitive price setting behavior of firms this latter aspect helps us control for the potential endogeneity generated by unmeasured product characteristics in aggregate data the channel controls for competitive aspects both between manufacturers and between manufacturers and a retailer despite this competition we find that targeted pricing need not generate the prisoner s dilemma in our data this contrasts with the findings of theoretical models due to the flexibility of the empirical model of demand the demand system we estimate captures richer forms of product differentiation both vertical and horizontal as well as a more flexible distribution of consumer heterogeneity

a likelihood approach to estimating market equilibrium models this paper develops a new likelihood based method for the simultaneous estimation of structural demand and supply models for markets with differentiated products we specify an individual level discrete choice model of demand and derive the supply side assuming manufacturers compete in prices the proposed estimation method considers price endogeneity through simultaneous estimation of demand and supply allows for consumer heterogeneity and incorporates a pricing rule consistent with economic theory the basic idea behind the proposed estimation procedure is to simulate prices and choice probabilities by solving for the market equilibrium by repeating this many times we obtain an empirical distribution of equilibrium prices and probabilities the empirical distribution is then smoothed and used in a likelihood procedure to estimate the parameters of the model the advantage of this method is that it avoids the need to perform a transformation of variables if the tastes of consumers are independent across market periods our approach yields maximum likelihood estimates otherwise it yields consistent but not fully efficient partial likelihood estimates

measuring market power in the ready to eat cereal industry the ready to eat cereal industry is characterized by high concentration high price cost margins large advertising to sales ratios and numerous introductions of new products previous researchers have concluded that the ready to eat cereal industry is a classic example of an industry with nearly collusive pricing behavior and intense nonprice competition this paper empirically examines this conclusion in particular i estimate price cost margins but more importantly i am able empirically to separate these margins into three sources i that which is due to product differentiation ii that which is due to multi product firm pricing and iii that due to potential price collusion the results suggest that given the demand for different brands of cereal the first two effects explain most of the observed price cost margins i conclude that prices in the industry are consistent with noncollusive pricing behavior despite the high price cost margins leading firms are able to maintain a portfolio of differentiated products and influence the perceived product quality it is these two factors that lead to high price cost margins

incentive contracting with asymmetric and imperfect precontractual knowledge abstract the pareto optimal contract between principal and risk neutral agent is analyzed for the case in which the agent s information is initially imperfect but better than that of the principal in contrast to the case where precontractual information is symmetric the final contract between principal and agent will not always guarantee an efficient outcome however in contrast to the case where the agent s information is initially perfect the agent may be unable to command rents from his superior information and the outcome will always be efficient the conditions under which efficient or inefficient outcomes are guaranteed differ qualitatively according to whether the random stete of nature follows a continuous or a discrete distribution journal of economic literature classification numbers 022 026 611

on modelling the natural rate of unemployment with indivisible labour this analysis investigates modelling the natural rate of unemployment in settings where labour s utilization has some lumpy aspect to it specifically the introduction of various nonconvexities into tastes and technology lead to unemploy ment in general equilibrium equilibria can emerge where 1 those currently unemployed have higher probabilities of being unemployed in the future than those currently employed 2 some agents are jobless while others work overtime and 3 seniority rules seemingly arise whereby old workers cannot be laid off so long as either new workers are being hired or some workers are doing overtime the relative welfare levels of employed and unemployed agents are analysed

employment with asymmetric information in an economy without informational and other distortions entrepreneurs and workers can write labor contracts that support a pareto optimal allocation of resources this paper is an attempt to characterize contracts when enterpreneurs are better informed about the state of nature than are their workers asymmetric information generally results in a suboptimal allocation of both risk and worker effort in particular if consumption and leisure are perfect substitutes employment will be less than fully pareto optimal in all but the most favorable states of nature

implicit contracts with asymmetric information and bankruptcy the effect of interest rates on layoffs this paper develops a model in which a firm writes labour contracts with workers and debt contracts with creditors firms have more information than do the owners of the factors of production and they are also subject to limited liability we show that if the limited liability constraint is binding then the employment level is inefficient relative to a situation of symmetric information the firm is then embedded into a partial equilibrium model in which the real rate of interest is exogenously determined we show that increases in the real rate of interest increase the inefficiency of the optimal employment contract and lead to layoffs in more states of nature than would occur at lower real interest rates recent literature in the area of implicit contracts has shown considerable interest in the assumption of asymmetric information henceforth a i papers by azariadis 1982 green and kahn 1982 and grossman and hart 1981 have all shown that a i will interfere with optimal risk sharing but although these models produce non walrasian outcomes it is not clear that they are capable of explaining the observed variations in employment over the business cycle in the absence of a link between the level of employment and other macroeconomic variables these new versions of contract theory are open to the charge that they are presenting a complicated explanation of frictional unemployment one potential link between variations in output and variations in intertemporal prices is suggested by models which explicitly allow for the possibility of bankruptcy sappington 1983 has shown that bankruptcy will generate inefficient outcomes even between risk neutral agents and farmer 1984 has shown that if sappington type contracts are incorporated into a macroeconomic structure then the resulting model predicts that bankruptcies will vary countercyclically over the business cycle although bankruptcy is important however it is unlikely that bankruptcies alone will account for all of the output loss during a recession the purpose of this paper is to show that the assumptions of a i and limited liability will generate a model in which the employment level is inefficient and in which the magnitude of this inefficiency varies systematically with the expected real rate of interest this model predicts that the observed increase in the incidence of layoffs during recessions is directly attributable to the effects of high interest rates on aggregate supply some evidence of the phenomenon to be explained is presented below

structural analysis of manufacturer pricing in the presence of a strategic retailer consumer goods manufacturers usually sell their brands to consumers through common independent retailers theoretical research on such channel structures has analyzed the optimal behavior of channel members under alternative assumptions of manufacturer retailer interaction vertical strategic interaction research in empirical industrial organization has focused on analyzing the competitive interactions between manufacturers horizontal strategic interaction decision support systems have made various assumptions about retailer pricing rules e g constant markup category profit maximization the appropriateness of such assumptions about strategic behavior for any specific market however is an empirical question this paper therefore empirically infers 1 the vertical strategic interaction vsi between manufacturers and retailer 2 the horizontal strategic interaction hsi between manufacturers simultaneously with the vsi and 3 the pricing rule used by a retailer the approach is particularly appealing because it can be used with widely available scanner data where there is no information on wholesale prices researchers usually have no access to wholesale prices even manufacturers who have access to their own wholesale prices usually have limited information on competitors wholesale prices in the absence of wholesale prices we derive formulae for wholesale prices using game theoretic solution techniques under the specific assumptions of vertical and horizontal strategic interaction and retailer pricing rules we then embed the formulae for wholesale prices into the estimation equations while our empirical illustration is using scanner data without wholesale prices the model itself can be applied when wholesale prices are available early research on the inference of hsi among manufacturers in setting wholesale prices using scanner data e g kadiyali et al 1996 1999 made the simplifying assumption that retailers charge a constant margin this assumption enabled them to infer wholesale prices and analyze competitive interactions between manufacturers in this paper we show that this model is econometrically identical to a model that measures retail price coordination across brands hence the inferred cooperation among manufacturers could be exaggerated by the coordinated pricing category management done by the retailer we find empirical support for this argument this highlights the need to properly model and infer vsi simultaneously to accurately estimate the hsi when using data at the retail level functional forms of demand have been evaluated in terms of the fit of the model to sales data but recent theoretical research on channels lee and staelin 1997 tyagi 1999 has shown that the functional form has serious implications for strategic behavior such as retail passthrough while the logit and linear model implies equilibrium passthrough of less than 100 lee and staelin call this vertical strategic substitute vss the multiplicative model implies optimal passthrough of greater than 100 vertical strategic complement vsc because passthrough rates on promotions have been found to be below or above 100 chevalier and curhan 1976 armstrong 1991 we empirically test the appropriateness of the logit vss and the multiplicative vsc functional form for the data we perform our analysis in the yogurt and peanut butter categories for the two biggest stores in a local market we found that the vss implications of the logit fit the data better than the multiplicative model we also find that for both categories the best fitting model is one in which 1 the retailer maximizes category profits 2 the vsi is manufacturer stackelberg and 3 manufacturer pricing hsi is tacitly collusive the fact that the retailer maximizes category profits is consistent with theoretical expectations the inference that the vsi is manufacturer stackelberg reflects the institutional reality of the timing of the game retailers set their retail prices after manufacturers set their wholesale prices note that in the stores and product categories that we analyze the two manufacturers own the dominant brands with combined market shares of about 82 in the yogurt market and 65 in the peanut butter market the result is also consistent with a balance of power argument in the literature the finding that manufacturer pricing is tacitly collusive is consistent with the argument that firms involved in long term competition in concentrated markets can achieve tacit collusion managers use decision support systems for promotion planning that routinely make assumptions about vsi hsi and the functional form the results from our analysis are of substantive import in judging the appropriateness of assumptions made in such decision support systems

optimal labour contracts and involuntary unemployment under costly and imperfect monitoring this paper provides an explanation for the concurrence of rigid wages and involuntary unemployment we consider cases in which a firm monitors its workers but at some cost a key assumption in the model is that the firm cannot perfectly distinguish shirkers from nonshirkers thus the firm has to rely on negotiated compensation and work effort as well as monitoring to reduce the incentive to shirk we find that rigid wages and involuntary unemployment arise simultaneously when monitoring costs are large and the effectiveness of monitoring is low

labor contracts and the role of monetary policy in an overlapping generations model abstract this paper characterizes labor contracts in a dynamic economy subject to both real and nominal shocks in this environment we compare alternative means of trading labor services spot markets fixed nominal wage contracts and price contingent contracts the welfare ordering of these market structures is shown to depend on the relative variability of the real and nominal shocks and the costs of contingent contracts the paper also investigates the role of monetary policy and the neutrality of feedback rules finally we demonstrate that the optimal policy is nonstochastic

beyond the endogeneity bias the effect of unmeasured brand characteristics on household level brand choice models we investigate the role of potential weekly brand specific characteristics that influence consumer choices but are unobserved or unmeasurable by the researcher we use an empirical approach based on the estimation methods used for standard random coefficients logit models to account for the presence of such unobserved attributes using household scanner panel data we find evidence that ignoring such time varying latent to the researcher characteristics can lead to two types of problems first consistent with previous literature we find that these unobserved characteristics may lead to biased estimates of the mean price response parameters this argument is based on a form of price endogeneity if marketing managers set prices based on consumer willingness to pay then the observed prices will likely be correlated with the latent to the researcher brand characteristics we resolve this problem by using an instrumental variables procedure our findings suggest that simply ignoring these attributes may also lead to larger estimates of the variance in the heterogeneity distribution of preferences and price sensitivities across households this could overstate the benefits from marketing activities such as household level targeting we resolve the problem by using weekly brand intercepts embedded in a random coefficients brand choice model to control for weekly brand specific characteristics while accounting for household heterogeneity overall our results extend the finding on the endogeneity bias from the mean of the heterogeneity distribution i e the price effect to include the variance of that distribution

modeling heterogeneity and state dependence in consumer choice behavior in frequently purchased consumer goods markets consumer brand choices exhibit substantial persistence across purchase occasions in this article i estimate a choice model that admits of both heterogeneity in preferences and true state dependence as sources of this persistence using nielsen scanner data on ketchup i find evidence for true state dependence in the choice process even after controlling for a rich heterogeneity structure simulation of the model indicates that the long term effect of a promotion induced purchase on future purchase probabilities is positive but small

logit demand estimation under competitive pricing behavior an equilibrium framework discrete choice models of demand have typically been estimated assuming that prices are exogenous since unobservable to the researcher product attributes such as coupon availability may impact consumer utility as well as price setting by firms we treat prices as endogenous specifically prices are assumed to be the equilibrium outcomes of nash competition among manufacturers and retailers to empirically validate the assumptions we estimate logit demand systems jointly with equilibrium pricing equations for two product categories using retail scanner data and cost data on factor prices in each category we find statistical evidence of price endogeneity we also find that the estimates of the price response parameter and the brand specific constants are generally biased downward when the endogeneity of prices is ignored our framework provides explicit estimates of the value created by a brand i e the difference between consumers willingness to pay for a brand and its cost of production we develop theoretical propositions about the relationship between value creation and competitive advantage for logit demand systems and use our empirical results to illustrate how firms use alternative value creation strategies to accomplish competitive advantage

theoretical foundations for sticky wages abstract the paper compares three different types of theoretical explanation of sticky wages they are implicit contracts efficiency wage models and insider outsider models it then reconsiders keynes rationale for sticky wages which focuses on relative wage issues finally the paper considers possible directions for future research

observed and unobserved preference heterogeneity in brand choice models this paper extends the scanner based choice literature by explicitly incorporating individual level brand preference data we illustrate our model using a unique data set that combines survey and scanner data collected from the same individuals the addition of individual specific brand preference information significantly improves fit and prediction furthermore this observed heterogeneity better explains choice than does unobserved heterogeneity in the standard scanner model s parameters more importantly we find that the standard model underestimates the importance of consumers brand preferences and overestimates both brand loyalties and price sensitivities brand loyalty is overestimated because models without preference information confound state dependence heterogeneity and preference effects price sensitivities are inflated because the average preference based consumer is implicitly assumed to be more willing to switch from his preferred brand than is the real preference based consumer further standard models overestimate the heterogeneity in price and loyalty sensitivities and misidentify both price and loyalty sensitive consumers the managerial implications of our findings and the applicability of our methodology when survey data are collected infrequently and for only a subsample of consumers are pursued we demonstrate that even under these circumstances better populationwide pricing and promotion decisions are identified and more accurate targeting results

the sensitivity of consumer search to wages abstract while intuition suggests that an increase in wages should increase the time cost of consumer search for low prices this note shows that under reasonable conditions the resulting increase in consumption actually increases search intensity

on allocative distortions in problems of self selection this article considers the general structure of self selection models by imposing conditions which permit the ordering of agents by their preferences we provide a characterization of the distortions inherent in the sorting process

endogeneity in semiparametric binary response models this paper develops and implements semiparametric methods for estimating binary response binary choice models with continuous endogenous regressors it extends existing results on semiparametric estimation in single index binary response models to the case of endogenous regressors it develops a control function approach to account for endogeneity in triangular and fully simulataneous binary response models the proposed estimation method is applied to estimate the income effect in a labor market participation problem using a large micro data set from the british fes the semiparametric estimator is found to perform well detecting a significant attenuation bias the proposed estimator is contrasted to the corresponding probit and linear probability specifications jel c14 c25 c35 j22

a simultaneous approach to the whether what and how much to buy questions consumer s purchase decisions of whether to buy what to buy and how much to buy are examined simultaneously based on a consumer utility maximization problem an unobservable threshold price about which a consumer pivots from nonpurchase to purchase can be deduced with any model specification the interrelationships between purchase decisions can be explicitly derived the model is applied to coffee purchasing data in addition by suppressing the nonpurchase options the model is compared with an alternative approach appearing in the marketing literature

a control function approach to endogeneity in consumer choice models abstract endogeneity arises for numerous reasons in models of consumer choice it leads to inconsistency with standard estimation methods that maintain independence between the model s error and the included variables the authors describe a control function approach for handling endogeneity in choice models observed variables and economic theory are used to derive controls for the dependence between the endogenous variable and the demand error the theory points to the relationships that contain information on the unobserved demand factor such as the pricing equation and the advertising equation the authors approach is an alternative to berry levinsohn and pakes s 1995 product market controls for unobserved quality the authors apply both methods to examine households choices among television options including basic and premium cable packages in which unobserved attributes such as quality of programming are expected to be correlated with price without correcting for endogeneity aggregate d

endogeneity and individual consumer choice abstract in many markets there is likely to be correlation both across periods in terms of the choices of one consumer and across consumers in terms of their choices in each period the former is caused by consumer heterogeneity and the latter may be the result of demand common shocks across consumers furthermore if firms partially observe these common shocks their market decisions may end up being endogenous and correlated with the common shocks because researchers cannot typically fully observe consumer heterogeneity and the common shocks the estimation method must account for the endogeneity of firms decisions in this article the authors present a test for endogeneity under unobserved consumer heterogeneity and common shocks which is based on a quasi likelihood estimation method to estimate the model parameters consistently when endogenous firm behavior unobserved heterogeneity and common shocks are present the test examines the differences in general method of moments coefficient estima

the value of purchase history data in target marketing an important aspect of marketing practice is the targeting of consumer segments for differential promotional activity the premise of this activity is that there exist distinct segments of homogeneous consumers who can be identified by readily available demographic information the increased availability of individual consumer panel data open the possibility of direct targeting of individual households the goal of this paper is to assess the information content of various information sets available for direct marketing purposes information on the consumer is obtained from the current and past purchase history as well as demographic characteristics we consider the situation in which the marketer may have access to a reasonably long purchase history which includes both the products purchased and information on the causal environment short of this complete purchase history we also consider more limited information sets which consist of only the current purchase occasion or only information on past product choice without causal variables proper evaluation of this information requires a flexible model of heterogeneity which can accommodate observable and unobservable heterogeneity as well as produce household level inferences for targeting purposes we develop new econometric methods to implement a random coefficient choice model in which the heterogeneity distribution is related to observable demographics we couple this approach to modeling heterogeneity with a target couponing problem in which coupons are customized to specific households on the basis of various information sets the couponing problem allows us to place a monetary value on the information sets our results indicate there exists a tremendous potential for improving the profitability of direct marketing efforts by more fully utilizing household purchase histories even rather short purchase histories can produce a net gain in revenue from target couponing which is 2 5 times the gain from blanket couponing the most popular current electronic couponing trigger strategy uses only one observation to customize the delivery of coupons surprisingly even the information contained in observing one purchase occasion boasts net couponing revenue by 50 more than that which would be gained by the blanket strategy this result coupled with increased competitive pressures will force targeted marketing strategies to become much more prevalent in the future than they are today

dynamic labor contracts under asymmetric information abstract this paper discusses the distortion of employment within a two period asymmetric information contracting model in which an exogenous demand shock is serially correlated and is known only to firms the obtained results show that serial correlations of the state of nature can cause not only underemployment but also overemployment even when overemployment never occurs in the context of a static asymmetric information contracting model

price uncertainty and consumer search a structural model of consideration set formation we offer an econometric framework that models consumer s consideration set formation as an outcome of her costly information search behavior because frequently purchased products are characterized by frequent price promotions of varying depths of discounts a consumer faces significant uncertainty about the prices of the brands the consumers engage in a fixed sample search strategy that results in their discovering the posted prices of a subset of the available brands this subset is referred to as the consumer s consideration set the proposed model is estimated using the scanner data set for liquid detergents our key empirical results are i consumers zincur significant search costs to discover the posted prices of the brands ii whereas in store displays and feature ads do not influence consumers quality perceptions of the brands they significantly reduce search costs for observing the prices of the brands iii per capita income of consumer s household significantly increases her search costs and iv the consumers price sensitivity is seriously underestimated if we were to assume that consumers get to know all the posted prices at zero cost the proposed model is also estimated for the ketchup category to enable us to do cross category comparisons of consumers price search behavior

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

multiple discreteness and product differentiation demand for carbonated soft drinks for several of the largest supermarket product categories such as carbonated soft drinks canned soups ready to eat cereals and cookies consumers regularly purchase assortments of products within the category consumers often purchase multiple products and multiple units of each alternative selected on a given trip this multiple discreteness violates the single unit purchase assumption of multinomial logit and probit models the misspecification of such demand models in categories exhibiting multiple discreteness would produce incorrect measures of consumer response to marketing mix variables in studying product strategy these models would lead to misleading managerial conclusions we use an alternative microeconomic model of demand for categories that exhibit the multiple discreteness problem recognizing the separation between the time of purchase and the time of consumption we model consumers purchasing bundles of goods in anticipation of a stream of consumption occasions before the next trip we apply the model to a panel of household purchases for carbonated soft drinks