not all rivals look alike estimating an equilibrium model of the release date timing game a very serious game of strategy is at work a cross between chess and chicken which studio distribution chiefs play year round but with increasing intensity during the summer and holiday release period new york times december 6 1999 hubris hubris if you only think about your own business you think i ve got a good story department i ve got a good marketing department we re going to go out and do this and you don t think that everybody else is thinking the same way in a given weekend in a year you ll have five movies open and there s certainly not enough people to go around joe roth chairman of walt disney studios answering a question about the large number of major movies opening within days of each other los angeles times december 31 1996 i introduction the number of americans who go to the movies varies dramatically over the course of the year and sometimes more than doubles within a period of two weeks at the same time the first week accounts for almost 40 of the box office revenues of the average movie the combination of these two facts makes the timing of launching a new movie a major focus of attention for distributors of movies with virtually no subsequent price competition the movie s release date is one of the main short run vehicles by which studios compete with each other in this paper i develop and estimate a model of discrete games which allows me to analyze this release date timing game most empirical industry studies focus on price and quantity competition taking other product characteristics as given in many industries however prices play a very small role and competition is channeled through other product attributes the entertainment industry is a prime example competition among movies television programs or broadway shows is on nonmonetary product attributes such as content advertising and time therefore understanding competition in such industries requires a model that endogenizes some of these product attributes especially those that can be changed in the short run this paper provides a framework in which release decisions can be endogenized and nonprice competition can be analyzed the absence of price competition is useful because it allows the focus of the analysis to be on the timing dimension without relying on assumptions about the nature of the postrelease price competition 1 together with the frequent timing decisions associated with different movies this makes the motion picture industry quite attractive for empirical analysis of the timing game this industry however is not the only example in which timing decisions play a central role similar timing considerations are also important in the release decisions of books compact disks and other new products as well as in the scheduling decisions of major events television programs flight schedules and promotional sales 2 when taking on a new project distributors of movies typically plan for a friday release which falls within a relatively short window of time carefully chosen to match the type of the movie this makes the choice of the release date a very discrete one the exact friday within the season is generally determined by a strategic timing game played among distributors before each release season distributors scramble to release their movies on big holiday weekends when demand is high when doing so each distributor tries to release on the attractive holiday weekend and at the same time to deter competitors from doing the same the extent to which distributors are successful in doing so largely depends on the quality of the movies at their disposal and on the way they can compete with movies released by other studios thus modeling this timing game must account for the asymmetries among movies and for the variation in these asymmetries across release seasons specifically i develop and estimate a sequential move game with private information i assume that the observed release date decisions are the equilibrium outcome of such a game

outsourcing retail pricing to a category captain the role of information firewalls it has been argued that retailers lack both the resources and capabilities to maximize category performance retailers may seek category management cm advice from a manufacturer referred to as a category captain cc a cc s recommendations affect all brands in the category not just her own despite an increase in the number of cc collaborations retailers are still concerned about manufacturer opportunism and militant behavior by manufacturers not selected as ccs whereas government agencies are worried about anticompetitive behavior that could harm consumers the federal trade commission recommends strictly enforced information firewalls within a cc s organization as a best practice guideline in this study we develop an empirical model and use policy simulations to quantify the impact of cc arrangements with information firewalls on retailers manufacturers and consumers we show how these effects could be influenced by the deactivation of vertical and horizontal information firewalls within the cc s organization

additional information for comments on alternative models of demand for automobiles by charlotte wojcik abstract in a recent paper in this journal econ lett 68 2000 113 wojcik argues that the nested logit is likely to be superior to demand specifications we and others have used in recent empirical work we review the relevant models and their uses consider her application and find that her conclusions are incorrect

new products quality changes and welfare measures computed from estimated demand systems this paper examines the construction of a price index based on an estimated demand system in principle the method examined can produce a price index that takes account of the introduction of new p

identification of the oligopoly solution concept in a differentiated products industry a central part of the new empirical industrial organization has been the study of market power in homogenous product industries this paper discusses extension of these methods to differentiated products industries the requirements for identification of conjectural variation parameters are shown to be hard to satisfy in practice an alternative menu approach is discussed 1998 elsevier science s a

price elasticities and demand side real rigidities in micro data and in macro models abstract high degrees of demand side real rigidities are able to generate the large monetary non neutrality found in aggregate data this paper provides micro based evidence on the key parameters governing this rigidity using european homescan data we find strong evidence for demand side real rigidity which is however significantly lower than that normally assumed in macro models in a menu cost model calibrated to our estimates we show that these estimates are associated with reasonable values for production side parameters but they are not able to generate the degree of monetary non neutrality observed in macro data

spatial differentiation and vertical mergers in retail markets for gasoline this paper studies an empirical model of spatial competition applied to gasoline markets the main feature is to specify commuting paths as the locations of consumers in a hotelling style model as a result spatial differentiation depends in an intuitive way on the structure of the road network and the direction of traffic flows the model is estimated using panel data on the quebec city gasoline market and used to evaluate the consequences of a recent vertical merger difference in difference and counterfactual simulation methods are compared and the results to a large extent validate the assumptions of the demand model jel g34 l13 l42 l81 q41 r41

endogeneity and simultaneity in competitive pricing and advertising a logit demand analysis in this article we use four data sets to provide a benchmark study of the effects of accounting for endogeneity and simultaneity in estimating marketing mix effects in a logit demand framework we compare the results obtained from accounting for endogeneity only to those from accounting for both endogeneity and simultaneity and in the latter case we allow for more general models of firm behavior to examine the consequences of imposing assumptions about the behavior of firms we find that accounting for both endogeneity and simultaneity not only affects the parameter estimates but also results in efficiency gains that affect the statistical significance of the estimates

horatio alger meets the mobility tables the question of how entrepreneurship relates to income mobility is cogent given the current public debate about the sources of income inequality and mobility in united states society we examine how experience with entrepreneurship has affected an individual s place in the earnings distribution our basic tack is to follow individuals positions in the income distribution over time and to see how their mobility or lack thereof was affected by involvement with entrepreneurship our main finding is that for low income individuals there is some merit to the notion that the self employed moved ahead in the earnings distribution relative to those who remained wage earners on the other hand for those at the upper end of the earnings distribution those who became self employed often advanced less in the earnings distribution than their salaried counterparts

mergers with differentiated products the case of the ready to eat cereal industry traditional merger analysis is difficult to implement when evaluating mergers in industries with differentiated products i discuss an alternative which consists of demand estimation and the use of a model of postmerger conduct to simulate the competitive effects of a merger i estimate a brand level demand system for ready to eat cereal using supermarket scanner data and use the estimates to 1 recover marginal costs 2 simulate postmerger price equilibria and 3 compute welfare effects under a variety of assumptions the methodology is applied to five mergers two of which occurred and for which i compare predicted to actual outcomes

discrete choice models with multiple unobserved choice characteristics since the pioneering work by daniel mcfadden utility maximization based multinomial response models have become important tools of empirical researchers various generalizations of these models have been developed to allow for unobserved heterogeneity in taste parameters and choice characteristics here we investigate how rich a specification of the unobserved components is needed to rationalize arbitrary choice patterns in settings with many individual decision makers multiple markets and large choice sets we find that if one restricts the utility function to be monotone in the unobserved choice characteristics then up to two unobserved choice characteristics may be needed to rationalize the choices

an empirical investigation of private label supply by national label producers private labels pls are ubiquitous in several categories including groceries apparel and appliances however existing empirical work has not examined the differential impact of various upstream supply arrangements for pl products or the strategic motives for pl supply to do so requires one to model the interaction between private and national label nl products both upstream and downstream while accounting for strategic behavior on the part of manufacturers and retailers and retaining essential differences between nl and pl products we build a model that satisfies these requirements and lets us answer our two research questions first can an nl firm profit from being an outsourced pl supplier second what are the upstream and downstream impacts of different pl supply arrangements we answer these questions by modeling private labels as homogenous products at wholesale but as differentiated products at retail in contrast national label products are differentiated at both wholesale and retail levels using structural model estimates for fluid milk in a major metropolitan area we conduct three counterfactual experiments we find that both nl producers and retailers profit from adding private labels we also find that a vertically integrated supply of pl leads to lower prices for end consumers

forecasting marketing mix responsiveness for new products abstract before a new product launch marketers need to infer how demand will respond to various levels of marketing mix variables to set an appropriate marketing plan a critical challenge in estimating marketing mix responsiveness from historical data is that the observed decisions were affected by private information possessed by managers about the heterogeneous effects of marketing mix variables on sales the authors refer to this as the slope endogeneity problem such endogeneity differs from the intercept endogeneity problem which has been widely acknowledged in the literature to correct for the slope endogeneity bias the authors develop a conceptually simple control function approach that is amenable to multiple endogenous variables and marketing mix carryover effects the method is applied to forecasting advertising responsiveness in the u s dvd market the results suggest that advertising responsiveness varies substantially across dvd titles and that estimated marketing mix elasticities w

combining micro and macro data in microeconometric models or panel samples to improve accuracy of estimation in this paper we show how to do this efficiently we show that the gains from use of marginal information can be substantial we also discuss how to test the compatibility of sample and marginal information

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

the effects of banning advertising in junk food markets we develop a structural model to analyze the eects of banning advertising on market equilibria and welfare in junk food markets we consider the impact on demand and prices and show how to quantify welfare eects when advertising might lead consumers to take decisions that are inconsistent with their underlying preferences we use transaction level data on the potato chips market and nd that banning advertising leads to a direct reduction in demand but also toughens price competition leading to lower prices and increased demand welfare increases as consumers benet from no longer making distorted

cost pass through in differentiated product markets the case of u s processed cheese in this paper we estimate a mixed logit model for demand in the u s processed cheese market the estimates are used to determine pass through rates of cost changes under different behavioral regimes we find that under collusion the pass through rates for all brands fall between 21 and 31 while under nash bertrand price competition the range of pass through rates is between 73 and 103 the mixed logit model provides a more flexible framework for studying pass through rates than the logit model since the curvature of the demand functions depends upon the empirical distribution of consumer types

controlling opportunism in vertical contracting when production precedes sales in a make to stock vertical contracting setting with private contracts when retailers do not observe each other s stocks before choosing their prices an opportunism problem always exist in contract equilibria but public market wide resale price maintenance rpm can restore monopoly power however other widely used tools which do not fall under antitrust scrutiny and require only private bilateral contracts such as buyback contracts also allow the producer to fully exercise his monopoly power we conclude that a more lenient policy toward rpm is unlikely to affect the producer s ability to control opportunism

competition and collusion in the american automobile industry the 1955 price war movements in total quantity and in quality adjusted price suggest a supply side shock in the american automobile market in 1955 this paper tests the hypothesis that the shock was a transitory change in industry conduct a price war the key ingredients of the test are alternative equilibrium models of oligopoly under product differentiation in nonnested cox tests of hypotheses a collusive solution is sustained in 1954 and in 1956 while a competitive solution holds in 1955 the result does not appear to be an artifact since it is robust in tests against alternative specifications copyright 1987 by blackwell publishing ltd

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

estimating multiple discrete choice models an application to computerization returns buyers in many markets face multiple discrete choices they can purchase multiple units as well as multiple brands at the same time this paper presents a multiple discrete choice model for the analysis of differentiated products demand users maximize profits by choosing the number of units of each brand they purchase i estimate the model using micro level data on the demand for personal computers i use the estimated demand structure to assess the welfare gains from computerization and technological innovation in peripherals the estimated return on investment in personal computers is 92 moreover a 10 increase in the performance to price ratio of microprocessors leads to a 2 2 gain in the estimated user surplus the personal computer pc market is of interest to industrial organization economists because of its size the continual technological change and above all because of the farreaching implications of pcs on the economy as a whole several distinct features make pc demand difficult to model pcs are a differentiated durable good in constant technological evolution moreover buyers make multiple discrete choices firms according to our data spread their purchases of pcs over different brands at the same time they buy pcs in blocks several units of each brand that they have chosen the aim of the paper is to present a model that captures these features and to use this model to estimate the welfare gains from computerization classical discrete choice models allow one choice among mutually exclusive alternatives in contrast the proposed framework allows users to demand multiple units and multiple brands the model can be applied to other cases of multiple discrete choices e g the composition of airline fleets car holdings per household the fields of the faculty in economics departments household cereals consumption or any other good consumed in more than one variety during a relevant time period although pervasive multiple discrete choice problems have received little attention because of their complexity a central issue regarding the pc market is the current controversy in the economics literature about the computerization puzzle this puzzle stems from the empirical finding that computerization has had no effect on firm productivity griliches and siegel 1991 and morrison and berndt 1990 contrary to those results hendel 1994 and lichtenberg 1995 using more disaggregate data than most previous studies report excess returns to computerization this indicates that data aggregation may have created the computerization puzzle in this paper i present a model consistent with the basic

assessing the effect of payroll taxes on formal employment the case of the 2012 tax reform in colombia in 2013 colombia implemented a tax reform that reduced payroll taxes by a total of 13 5 percentage points of wages this paper evaluates the effects of this component of the 2012 colombian tax reform on firms formal employment and average wages we construct a panel of firms based on their employees administrative records to account for the endogeneity of the treatment we use an instrumental variables technique that exploits the exogenous variation from the decisions of firms that are similar to each other in several dimensions but belong to different economic sectors based on our preferred specification we estimate a positive and significant increase in formal employment as a result of the implementation of the reform of approximately 213 000 jobs in existing pre reform firms in the long run these effects will increase to more than 600 000 jobs the effect of the reform on the average wages paid by firms was also found to be positive for some sizes of firms but the overall effect in the short run is rather small

exclusive dealing as a barrier to entry evidence from automobiles exclusive dealing contracts between manufacturers and retailers force new entrants to set up their own costly dealer networks to enter the market we ask whether such contracts may act as an entry barrier and provide an empirical analysis of the european car market we first estimate a demand model with product and spatial differentiation and quantify consumers valuations for dealer proximity and dealer exclusivity we then perform policy counterfactuals to assess the profit incentives and possible entry deterring effects of exclusive dealing we find that there are no unilateral incentives to maintain exclusive dealing but there is a collective incentive for the industry as a whole furthermore a ban on exclusive dealing would raise the smaller entrants market share but more importantly consumers would gain not so much because of increased price competition but rather because of the increased spatial availability which compensates for the demand inefficiency from a loss of dealer exclusivity

sticker shocks using vat changes to estimate upper level elasticities of substitution we estimate the upper level elasticity of substitution between goods and services of a nested aggregate ces preference specification we show how this elasticity can be derived from the long run response of the relative price of a good to a change in its vat rate we estimate this elasticity using new data on changes in vat rates across 74 goods and services for 25 european union countries from 1996 through 2015 depending on the level of aggregation we find a vat pass through rate between 0 4 and 0 7 this implies an upper level elasticity of 3 at the lowest level of aggregation with 74 categories and 1 cobb douglas preferences at a high level of aggregation that distinguishes 10 categories of goods and services

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

tax incidence with strategic firms in the soft drink market abstract because soft drink sd consumption is considered to be a contributor to the epidemic of obesity there is a growing interest in evaluating the impact on sd consumption of alternative tax policies in this paper we propose a methodology to evaluate the impact of taxation of a food market taking into account the strategic price response of both manufacturers and retailers we apply this methodology to the french sd market and simulate the impacts of ad valorem and excise taxes we find that firms behave differently when facing an ad valorem tax or an excise tax an excise tax is overshifted to consumer prices while an ad valorem tax is undershifted to consumer prices we find that an excise tax based on the sugar content of sd is the most effective at reducing sd consumption our results also indicate that ignoring strategic pricing by firms leads to misestimations of the impact of taxation by between 15 and 40 depending on the products and the tax implemented in the short term that is ignoring positive long term health effects a 9 cents l excise tax has a small negative welfare effect about 1 person year

a structural approach to identifying the sources of local currency price stability the inertia of the local currency prices of traded goods in the face of exchange rate changes is a well documented phenomenon in international economics this paper develops a structural model to identify the sources of this local currency price stability and applies it to micro data from the beer market the empirical procedure exploits manufacturers and retailers first order conditions in conjunction with detailed information on the frequency of price adjustments following exchange rate changes to quantify the relative importance of local non traded cost components markup adjustment by manufacturers and retailers and nominal price rigidities in the incomplete transmission of such changes to prices we find that on average approximately 60 of the incomplete exchange rate pass through is due to local non traded costs 8 to markup adjustment 30 to the existence of own brand price adjustment costs and 1 to the indirect strategic effect of such costs though these results vary considerably across individual brands according to their market shares

endogeneity and heterogeneity in a probit demand model estimation using aggregate data two issues that have become increasingly important while estimating the parameters of aggregate demand functions to study firm behavior are theendogeneity of marketing activities typically price andheterogeneity across consumers in the market under consideration ignoring these issues in the estimation of the demand function parameters can lead to biased and inconsistent estimates for the effects of marketing activities endogeneity and heterogeneity have achieved prominence in large measure because of the increasing popularity of logit models to characterize demand functions usingaggregate data the logit model accounts for purchase incidence and brand choice by including a no purchase alternative in the consumer s choice set this allows for category sales to change as a function of the marketing activities of brands in the category there are three issues with using the logit model with the no purchase option to characterize demand when studying competitive interactions among firms 1 the marketing literature dealing with brand choice behavior at the consumer level has found that the iia restriction is not appropriate as each brand in the choice set is more similar to some brands than it is to others 2 studies have found that the purchase incidence decision is distinct from the brand choice decision hence it may not be appropriate to model the no purchase decision as just another alternative in the choice set with the iia restriction holding across all brands and the no purchase option 3 even if the distinction between the purchase incidence and brand choice decisions is accounted for via for example a nested logit specification accounting for the purchase incidence decision with aggregate data requires assumptions for computing the share of the no purchase alternative which is otherwise unobserved in this paper we propose a probit model as an alternative to the logit model to specify the aggregate demand functions of firms competing in oligopoly markets the probit model avoids the iia property that affects the logit model at the individual consumer level furthermore the probit model can naturally account for the distinction between the purchase incidence and brand choice decisions due to the general covariance structure assumed for the utilities of the alternatives we demonstrate how the parameters of the proposed model can be estimated using aggregate time series data from a product market in the estimation we account for the endogeneity of marketing variables as well as for heterogeneity across consumers our results indicate that both endogeneity as well as heterogeneity need to be accounted for even after allowing for a non iia specification at the individual consumer level specific to our data we also find that ignoring endogeneity has a bigger impact on the estimated price elasticities than ignoring the effects of heterogeneity a comparison of the elasticities obtained from the probit model with those from the corresponding logit specification indicates that therange of elasticities obtained from the probit model across brands is larger than that obtained from the logit the results have implications for issues such as firm level pricing in addition to specifying a probit model and providing comparisons with the logit model the paper also addresses the third issue raised above we propose a simple alternative to the purchase incidence brand choice specification by decomposing the demand for a brand into a category demand equation and a conditional brand choice share equation we provide a comparison of results from this specification to those from the specification that includes the no purchase alternative and find that estimated elasticities are sensitive to the specification used we also estimate the demand function parameters using a traditional specification such as the double logarithmic model here we find that the estimated elasticities could be signed in such a manner as to be not useful for firm level pricing decisions one of the key limitations of the proposed model is that while it accounts for the purchase incidence and brand choice decisions of households it does not account for differences across consumers in their purchase quantities the model and analysis are best suited for product categories in which consumers typically make single unit purchases another limitation is more practical in nature while recent advances have been made in computing probit probabilities it could nevertheless be a challenge to do so when the number of alternatives is large