Analysis of Sales Promotion Effects on Household Purchase Behavior

2.3.2.2 Operant Conditioning
In operant conditioning, current behavior is influenced by the consequences <strong>of</strong> previous
behavior. The basic purport <strong>of</strong> operant conditioning is that reinforced behavior is more
likely to persist. A reinforcer is anything that occurs after a behavior and changed the
likelihood that it will be emitted again. Once the reinforcement is stopped, the so-called
extinction effect might change behavior back to as it was before. Purchasing the brand is
the behavior we want to teach consumers, and a promotion could serve as the
reinforcement (for example an in-pack coupon). The goal is to use promotions to build up
purchase frequency, but to do this in a way so as to mitigate the extinction effect (when the
promotion is withdrawn, we want the behavior to continue).
The distinction between classical conditioning and operant conditioning can be
understood most easily as a difference in sequence. In classical conditioning, a stimulus
occurs first, and a response is elicited. Classical conditioning can thus be called a stimulusresponse
theory. In operant conditioning, the response is first emitted and then reinforced.
Operant conditioning can thus be called a response-reinforcement theory.
An example <strong>of</strong> a model, which incorporates the idea <strong>of</strong> operant conditioning, is
the so-called linear learning model (e.g., Bush and Mosteller 1955, Wierenga 1974, Lilien
1974, Leeflang and Boonstra 1982). In this model, the probability Pn that some specific
brand will be purchased on the n-th purchase occasion depends linearly on the probability
that it was purchased at the previous occasion and on whether or not it was actually bought
at that occasion. That is, if we let In denote the indicator function that is 1 if the brand was
purchased on occasion n and 0 otherwise, Pn = α + β I n−
1 + λ P , whereα , β , λ ≥ 0 and
n−
1
(α +β +λ )≤ 1. Normally it is assumed that there is a positive learning effect (β >0). <strong>Sales</strong>
promotions can induce consumers to switch brands, which, according to the linear learning
model, would lead to an increase in repeat purchase probability for that specific brand the
consumers switched toward. But, it could also be the case that the β coefficient in this case
is smaller than had the brand been purchased not on promotion.
A major concern associated with both the operant and classical conditioning
viewpoint is their explicit exclusion <strong>of</strong> attitude and mental processes. Applying the
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