The workhorse brand choice models in marketing are the multinomial logit (MNL) and nested multino... more The workhorse brand choice models in marketing are the multinomial logit (MNL) and nested multinomial logit (NMNL). These models place strong restrictions on how brand share and purchase incidence price elasticities are related. In this paper, we propose a new model of brand choice, the “price consideration” (PC) model, that allows more flexibility in this relationship. In the PC model,
Research examining the process of individual decision making over time is briefly reviewed. We fo... more Research examining the process of individual decision making over time is briefly reviewed. We focus on two major areas of work in choice dynamics: research that has examined how current choices are influenced by the history of previous choices, and newer work examining how choices may be made to exploit expectations about options available in the future. A central theme
In this paper, we develop a structural model of household behavior in an environment where there ... more In this paper, we develop a structural model of household behavior in an environment where there is uncertainty about brand attributes, and both prices and advertising signal brand quality. Four quality signaling mechanisms are at work in the model: 1) price signals quality, 2) advertising frequency signals quality, 3) advertising content provides direct (but noisy) information about quality, and 4) use experience provides direct (but noisy) information about quality. We estimate our proposed model using scanner panel data on ketchup. If price is important as a signal of brand quality, then frequent price promotion may have the unintended consequence of reducing brand equity. We use our estimated model to measure the importance of such effects. Our results imply that price is an important quality signaling mechanism, and that frequent price cuts can have significant adverse effects on brand equity. The role of advertising frequency in signaling quality is also significant, but it is less quantitatively important than price.
Religion is a powerful force in many people's lives, impacting decisions about life, death, a... more Religion is a powerful force in many people's lives, impacting decisions about life, death, and everything in between. It may be difficult, then, to imagine that something as seemingly innocuous as the usage of brand name products might influence individuals' commitment to religion. However, we demonstrate across 6 studies that when brands are a highly salient tool for self-expression, individuals are less likely to report and demonstrate strong religious commitment. We suggest that a desire to maintain consistency among self-identities is one important driver of this relationship and find that the effect is mitigated when the perceived distance between brands and religious values is minimized.
We develop a model of household demand for frequently purchased consumer goods that are branded, ... more We develop a model of household demand for frequently purchased consumer goods that are branded, storable and subject to stochastic price fluctuations. Our framework accounts for how inventories and expectations of future prices affect current period purchase decisions. We estimate our model using scanner data for the ketchup category. Our results indicate that price expectations and the nature of the price process have important effects on demand elasticities. Long-run cross price elasticities of demand are more than twice as great as short-run cross price elasticities. Temporary price cuts (or ''deals'') primarily generate purchase acceleration and category expansion, rather than brand switching.
ABSTRACT Models of consumer learning and inventory behavior have both proven to be valuable for e... more ABSTRACT Models of consumer learning and inventory behavior have both proven to be valuable for explaining consumer choice dynamics. In their pure form these models assume consumers solve complex dynamic programming (DP) problems to determine optimal choices. For this reason, these models are best viewed as “as if” approximations to consumer behavior. In this paper we present an estimation method, based on Geweke and Keane (2000), which allows us to estimate dynamic models without solving a DP problem and without strong assumptions about how consumers form expectations about the future. The relatively low computational burden of this method allows us to nest the learning and inventory models. We also incorporate the “price consideration” mechanism of Ching et al. (2009), which essentially says that consumers may not pay attention to a category in every period. The resulting model may be viewed as providing a more “realistic” or “descriptive” account of consumer choice behavior.
ABSTRACT To measure the extent of incomplete information about brand qualities faced by consumers... more ABSTRACT To measure the extent of incomplete information about brand qualities faced by consumers, recent research in marketing and economics has extended traditional static choice models to explicitly allow for consumer learning. These models tend to be complicated and make stringent assumptions such as Bayesian updating. In this paper, we provide a simpler alternative method to measure how much consumers know about the quality of quasi-durable products. Our key insight is that for products that depreciate over time and require repeated purchases, individuals' observed inter-purchase spells provide an objective measure of brand qualities in terms of durability. This is simply because the higher the durability, the longer a product can last in general, and hence its observed inter-purchase spells should also be longer. Based on this argument, we use a scanner panel data set for diapers to estimate both the subjective perceived brand qualities (based on revealed preference data) and the objective brand qualities (based on brand-specific inter-purchase spells). Our estimates allow us to compare these two measures of qualities and infer the extent of incomplete information faced by parents. With our results, we can address questions such as: Do parents make the right choice in the diapers category? Can they save some money by switching from a national brand to a store brand, or the other way around? How much savings can they get?
Permeability changes in the blood-brain barrier (BBB) and their possible contribution to brain ed... more Permeability changes in the blood-brain barrier (BBB) and their possible contribution to brain edema formation have a crucial role in the pathophysiology of septic encephalopathy. Magnesium sulfate has been shown to have a protective effect on BBB integrity in multiple experimental models. In this study we determine whether magnesium sulfate administration could have any protective effects on BBB derangement in a rat model of sepsis. This randomized controlled experimental study was performed on adult male Sprague-Dawley rats. Intraperitoneal sepsis was induced by using the infected fibrin-thrombin clot model. To examine the effect of magnesium in septic and sham-operated rats, a dose of 750 micromol/kg magnesium sulfate was given intramuscularly immediately after surgery. Control groups for both infected and sham-operated rats were injected with equal volume of saline. Those rats surviving for 24 hours were anesthetized and decapitated for the investigation of brain tissue specific...
We are delighted that you are here in San Antonio to participate in an exchange of ideas, researc... more We are delighted that you are here in San Antonio to participate in an exchange of ideas, research, and films related to consumers. We are excited that you have traveled from around the world to contribute and that you will share your stimulating and fresh theoretical, substantive and methodological insights with us.
The workhorse brand choice models in marketing are the multinomial logit (MNL) and nested multino... more The workhorse brand choice models in marketing are the multinomial logit (MNL) and nested multinomial logit (NMNL). These models place strong restrictions on how brand share and purchase incidence price elasticities are related. In this paper, we propose a new model of brand choice, the “price consideration” (PC) model, that allows more flexibility in this relationship. In the PC model,
Research examining the process of individual decision making over time is briefly reviewed. We fo... more Research examining the process of individual decision making over time is briefly reviewed. We focus on two major areas of work in choice dynamics: research that has examined how current choices are influenced by the history of previous choices, and newer work examining how choices may be made to exploit expectations about options available in the future. A central theme
In this paper, we develop a structural model of household behavior in an environment where there ... more In this paper, we develop a structural model of household behavior in an environment where there is uncertainty about brand attributes, and both prices and advertising signal brand quality. Four quality signaling mechanisms are at work in the model: 1) price signals quality, 2) advertising frequency signals quality, 3) advertising content provides direct (but noisy) information about quality, and 4) use experience provides direct (but noisy) information about quality. We estimate our proposed model using scanner panel data on ketchup. If price is important as a signal of brand quality, then frequent price promotion may have the unintended consequence of reducing brand equity. We use our estimated model to measure the importance of such effects. Our results imply that price is an important quality signaling mechanism, and that frequent price cuts can have significant adverse effects on brand equity. The role of advertising frequency in signaling quality is also significant, but it is less quantitatively important than price.
Religion is a powerful force in many people's lives, impacting decisions about life, death, a... more Religion is a powerful force in many people's lives, impacting decisions about life, death, and everything in between. It may be difficult, then, to imagine that something as seemingly innocuous as the usage of brand name products might influence individuals' commitment to religion. However, we demonstrate across 6 studies that when brands are a highly salient tool for self-expression, individuals are less likely to report and demonstrate strong religious commitment. We suggest that a desire to maintain consistency among self-identities is one important driver of this relationship and find that the effect is mitigated when the perceived distance between brands and religious values is minimized.
We develop a model of household demand for frequently purchased consumer goods that are branded, ... more We develop a model of household demand for frequently purchased consumer goods that are branded, storable and subject to stochastic price fluctuations. Our framework accounts for how inventories and expectations of future prices affect current period purchase decisions. We estimate our model using scanner data for the ketchup category. Our results indicate that price expectations and the nature of the price process have important effects on demand elasticities. Long-run cross price elasticities of demand are more than twice as great as short-run cross price elasticities. Temporary price cuts (or ''deals'') primarily generate purchase acceleration and category expansion, rather than brand switching.
ABSTRACT Models of consumer learning and inventory behavior have both proven to be valuable for e... more ABSTRACT Models of consumer learning and inventory behavior have both proven to be valuable for explaining consumer choice dynamics. In their pure form these models assume consumers solve complex dynamic programming (DP) problems to determine optimal choices. For this reason, these models are best viewed as “as if” approximations to consumer behavior. In this paper we present an estimation method, based on Geweke and Keane (2000), which allows us to estimate dynamic models without solving a DP problem and without strong assumptions about how consumers form expectations about the future. The relatively low computational burden of this method allows us to nest the learning and inventory models. We also incorporate the “price consideration” mechanism of Ching et al. (2009), which essentially says that consumers may not pay attention to a category in every period. The resulting model may be viewed as providing a more “realistic” or “descriptive” account of consumer choice behavior.
ABSTRACT To measure the extent of incomplete information about brand qualities faced by consumers... more ABSTRACT To measure the extent of incomplete information about brand qualities faced by consumers, recent research in marketing and economics has extended traditional static choice models to explicitly allow for consumer learning. These models tend to be complicated and make stringent assumptions such as Bayesian updating. In this paper, we provide a simpler alternative method to measure how much consumers know about the quality of quasi-durable products. Our key insight is that for products that depreciate over time and require repeated purchases, individuals' observed inter-purchase spells provide an objective measure of brand qualities in terms of durability. This is simply because the higher the durability, the longer a product can last in general, and hence its observed inter-purchase spells should also be longer. Based on this argument, we use a scanner panel data set for diapers to estimate both the subjective perceived brand qualities (based on revealed preference data) and the objective brand qualities (based on brand-specific inter-purchase spells). Our estimates allow us to compare these two measures of qualities and infer the extent of incomplete information faced by parents. With our results, we can address questions such as: Do parents make the right choice in the diapers category? Can they save some money by switching from a national brand to a store brand, or the other way around? How much savings can they get?
Permeability changes in the blood-brain barrier (BBB) and their possible contribution to brain ed... more Permeability changes in the blood-brain barrier (BBB) and their possible contribution to brain edema formation have a crucial role in the pathophysiology of septic encephalopathy. Magnesium sulfate has been shown to have a protective effect on BBB integrity in multiple experimental models. In this study we determine whether magnesium sulfate administration could have any protective effects on BBB derangement in a rat model of sepsis. This randomized controlled experimental study was performed on adult male Sprague-Dawley rats. Intraperitoneal sepsis was induced by using the infected fibrin-thrombin clot model. To examine the effect of magnesium in septic and sham-operated rats, a dose of 750 micromol/kg magnesium sulfate was given intramuscularly immediately after surgery. Control groups for both infected and sham-operated rats were injected with equal volume of saline. Those rats surviving for 24 hours were anesthetized and decapitated for the investigation of brain tissue specific...
We are delighted that you are here in San Antonio to participate in an exchange of ideas, researc... more We are delighted that you are here in San Antonio to participate in an exchange of ideas, research, and films related to consumers. We are excited that you have traveled from around the world to contribute and that you will share your stimulating and fresh theoretical, substantive and methodological insights with us.
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