The commonly used market share models are all based on the implicit assumption of a homogeneous population. However, studies of individual brand choice behavior tend to reject this basic premise. In this paper we attempt to explain why market share models perform well in spite of this underlying...

The dynamic evolvement of market share of a brand in a frequently purchased product category can be driven by two effects, purchase reinforcement, and advertising carryover. The first depends on the actual experience with the brand while the second on the retention of its producer's messages. We...