The Dirichlet: A Comprehensive Model of Buying Behaviour

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“…The Dirichlet distribution has recently played an important role in consumer research and has been employed by Goodhardt et al (1985) to develop a comprehensive model of buying behavior known as the "Dirichlet model." The authors of this paper have used the Dirichlet model to investigate the complex patterns of multistore and multicenter purchasing revealed in urban shopping behavior (Wrigley andDunn 1984b, 1984~).…”

“…This implies (a) that the sequence and timing of 1's and 0's in y, is not important, so that k, and N, are sufficient statistics; and (b) that the probability of selecting alternative 1 (the city center) is constant over time, and may again be written as p i . The most important evidence in favor of the no time-dependence assumption in this context is the success of the Dirichlet model of consumer behavior in predicting complex patterns of multistore and multicenter purchasing (Goodhardt, Ehrenberg, and Chatfield 1985;Wrigley and h n 1984b;Kau and Ehrenberg 1984). A central assumption of the Dirichlet model is that consumers have fixed and constant probabilities of visiting particular stores/centers.…”

Modelling Creative Innovation

“…The marketing scientist Andrew Ehrenberg and colleagues (Goodhardt et al 1984) developed a classic model -termed a "Dirichlet" in honour of the nineteenthcentury German mathematician -in which it was assumed that consumers had no inherent brand preference and made choices based on chance and availability. It is thus not a great stretch to assume that people might copy in the same undirected way.…”

Loyalty — What can it really tell you?

“…The Dirichlet model 1 This measures repeat buying and makes some simple assumptions, eg that consumers tend to have split loyalties to each of several brands. The application of this model is associated closely with the work of Professor A. S. C. Ehrenberg from South Bank University, London, UK.…”