Modernizing consumer theory: some modeling efforts

Neoclassical consumer theory has been challenged recently on many fronts. Among them, choice among brands within product groups is a frequently encountered decision for the consumer and is not treated adequately in the present body of consumer theory. Indeed, substitution probably occurs most frequently within rather than between product groups. Brand loyalty is not adequately acknowledged in consumer choice. Frequently the consumer has no choice but to purchase from a particular product group when a periodic failure of a durable consumer good requires replacement. And, perhaps, most troubling of all, choices among purchases today, postponement via cash balances until tomorrow, or long-term investment are not adequately analyzed within the context of future consumption. This paper makes a start using noncontinuous modeling to combine choice among product groups with varying characteristics, the demand for cash balances, and long-term investment. It approaches the choice process in a more modern framework for consumers in the developed world, using prices of goods as one of a variety of characteristics and the “dollar’s worth” as a convenient unit of utility. Much remains to be done, but the paper suggests an appropriate framework for a beginning, and uses a nonlinear programming approach to derive some insights.