Structural models of complementary choices

This article reviews the rapidly growing literature on structural models of complementary choices. It discusses recent modeling developments and identifies promising areas for future research.     

On equitable social welfare functions satisfying the Weak Pareto Axiom: A complete characterization

The present paper examines the problem of aggregating infinite utility streams with a social welfare function that respects the Anonymity and Weak Pareto Axioms. The paper provides a complete characterization of domains (of the one period utilities) on which such an aggregation is possible. A social welfare function satisfying the Anonymity and Weak Pareto Axioms exists on precisely those domains that do not contain any set of the order type of the set of positive and negative integers. The criterion is applied to decide on possibility and impossibility results for a variety of domains. It is also used to provide an alternative formulation of the characterization result in terms of the accumulation points of the domain.     

Empirical Analysis of Indirect Network Effects in the Market for Personal Digital Assistants

We present a framework to measure empirically the size of indirect network effects in high-technology markets with competing incompatible technology standards. These indirect network effects arise due to inter-dependence in demand for hardware and compatible software. By modeling the joint determination of hardware sales and software availability in the market, we are able to describe the nature of demand inter-dependence and to measure the size of the indirect network effects. We apply the model to price and sales data from the industry for personal digital assistants (PDAs) along with the availability of software titles compatible with each PDA hardware standard. Our empirical results indicate significant indirect network effects. By July 2002, the network effect explains roughly 22% of the log-odds ratio of the sales of all Palm O/S compatible PDA-s to Microsoft O/S compatible PDA-s, where the remaining 78% reflects price and model features. We also use our model estimates to study the growth of the installed bases of Palm and Microsoft PDA hardware, with and without the availability of compatible third party software. We find that lack of third party software negatively impacts the evolution of the installed hardware bases of both formats. These results suggest PDA hardware firms would benefit from investing resources in increasing the provision of software for their products. We then compare the benefits of investments in software with investments in the quality of hardware technology. This exercise helps disentangle the potential for incremental hardware sales due to hardware quality improvement from that of positive feedback due to market software provision.     

Bankruptcy and optimality in a closed trading mass economy modelled as a non-cooperative game

In this paper we establish the existence of (a) an optimal bankruptcy rule which enables us to describe the Walrasian trading economy as a game with trade in fiat money; and (b) non- cooperative equilibrium points of this game which (in terms of prices and the final allocation yielded) include the competitive equilibrium points, and the accompanying money rate of interest (induced by borrowing at a central bank), when the bankruptcy rule is different from optimal.     

Consumer shopping orientations,non-store retailers,and consumers' patronage intentions: A multivariate investigation

Over the last few years, nonstore retailing has become an important and integral part of the American retailing scene. However, very little published research exists regarding these new methods of retailing. This study examines the role of consumers' shopping orientations, and type of nonstore method on consumers' patronage intentions of a set of selected products. The results are supportive of the two research hypotheses. Theoretical and managerial implications are discussed.     

Models of consumer behavior: The state of the art

Models of consumer behavior have gained much acceptance since the early sixties. The purpose of this article is to examine the state of the art by reviewing the often cited models: Nicosia, Howard-Sheth, and Engel-Blackwell-Kollat. Specifically, a major objective is to consider these models from their practical utility standpoint, i.e., whether the models can be tested and used by marketers. To accomplish this, a set of criteria is developed for evaluation of models in general, and consumer/buyer behavior models in particular. The criteria used for evaluating the state of the art in consumer behavior models are largely derived from model building sources in various fields. The results indicate that although the models are quite impressive in scope, they are inherently weak to be of much help to the marketing practitioner. Indeed, none of the models have been tested as a whole in their original form because they lack specificity and thus are difficult, if not impossible, to operationalize. This article is partially based on a paper which received an award in an Academy of Marketing Science student paper competioion. The Academy encourages scholarly work by various groups through annual competitions and awards.     

A pre-diffusion growth model of intentions and purchase

In this paper, we investigate whether information on the history of purchase intentions is useful in predicting actual purchase behavior. The research is motivated by two factors. The first factor is the empirical finding in the literature that measuring intentions just prior to purchase provides better predictions of actual purchase as compared to when these intentions are measured earlier. The second factor is the role of the timing of the formation of intentions prior to purchase. While one stream of literature based on preference fluency predicts that early formation of intentions is more likely to lead to actual purchase, the other stream based on the memory-based “recency” effect predicts that formation of intentions just prior to purchase is more likely to lead to actual purchase. Together, these two factors motivate the potential need to account for the entire history of intentions prior to purchase. A canonical example of a market where intention histories are tracked is the movie industry, where “first choice” movie watching intentions are tracked up to (and in some cases beyond) the time of release. Accommodating the history of intentions in an econometric model that predicts actual box office performance is challenging due to the differing numbers of observations for the movies, the large numbers of observations for certain movies, as well as the role of various time-invariant and time-varying covariates influencing intentions. We propose a two-part model where the first part involves a hierarchical growth model that summarizes the trajectories of intentions via “growth factors.” These growth factors also reflect the role of the various covariates. The second part is a regression of the box office performance on the growth factors and other covariates. The models are simultaneously estimated within a Bayesian framework. Consistent with the previous literature, we find that including information on intentions improves our ability to predict behavior, with the recent intentions being the most informative. Importantly, when the history of intentions is accounted for, our results indicate that the data support the “recency” literature—intentions grow over time leading up to purchase, and this growth has a positive impact on opening box office performance. While a linear growth model performs best for most movies, there exists a subset of movies for which the quadratic growth model better captures the “spike” in intentions just prior to purchase. Further, accounting for information on the history of intentions dramatically improves model fit and forecasting performance relative to when only the intentions at one point in time (e.g., the ones just prior to purchase) are accounted for.