Rational Inattention to Discrete Choice and Implications on Firm Decisions

Facing an abundance of product choices and related information, but with only limited time and attention to evaluate them, consumers have to come to grips with how much and what type of information to pay attention to (and what to ignore), and make product choice and purchase decisions based on this partial information. Evidently, it is often times easier to obtain information about some products then others (by the very nature of the product or simply because it is offered in an assortment and readily observable, among other reasons). At the same time there may be similarities (i.e., correlations) among products such that as the customer learns about a particular product, he/she may do so about another one. Utilizing rational inattention theory, we present a general discrete choice model that describes the choice behavior of customers who optimally acquire information about available options with ex-ante uncertain values through potentially different channels with different costs. Customers trade-off the benefits of better information obtained by asking questions (and receiving informative signals) with the associated cost. We quantify acquired information and its cost through a novel function based on (Shannon) mutual information. Solving the consumer’s choice problem, we analytically characterize the resulting optimal choice behaviour. Some special cases of this model (including the generalized multinomial choice) are analyzed to illustrate key properties.

We then turn our attention to the applications of this choice model to business operations. We discuss implications on assortment decisions of a seller as well as pricing decisions, demonstrating how salient factors such as limited attention, cost of information, and correlations among products shape these decisions.