Traditional economic models assume that the utility, or happiness, one gets from consuming an item depends only on how fundamentally useful the item is to the consumer. Under this model, an item’s utility must be independent from the price that the consumer paid for the item, since it’s hard to envision a scenario where the price paid for an item actually affects how useful it is (holding item quality and such constant, of course). Our own intuition, on the other hand, suggests that we get psychological warm fuzzies (or, conversely, cold…uh, slimies?) when we feel like we got a good deal on an item.
Behavioral economists recognize this phenomenon, and they even have a name for it- “transaction utility.” Under the behavioral model, the total utility that that an individual gets from an item is the sum of “acquisition utility” (roughly speaking, what traditional economists just call utility) and “transaction utility.” This model is interesting because it suggests that consumers can be convinced to buy stuff that they don’t rationally like enough to buy by making them feel like they are getting a good deal. (I think I’ve mentioned before how I am convinced that transaction utility is what keeps Christmas Tree Shops from going under.)
Economist Richard Thaler discusses the concept of transaction utility in his paper “Mental Accounting Matters”. In this paper, he gives the following anecdote to illustrate the irrational behavior that transaction utility can cause:
A friend of mine was once shopping for a quilted bedspread. She went to a department store and was pleased to find a model she liked on sale. The spreads came in three sizes: double, queen and king. The usual prices for these quilts were $200, $250 and $300 respectively, but during the sale they were all priced at only $150. My friend bought the king-size quilt and was quite pleased with her purchase, though the quilt did hang a bit over the sides of her double bed.
So let’s think about this- from what we know, we can probably infer that the double size quilt would give the friend the highest level of acquisition utility, since people generally like to have items that fit on the other items they are designed to go on. But the consumer is lured away from that choice by transaction utility, which is likely highest with the king-size quilt, since it had the biggest discount. (More specifically, the king-size quilt has the highest sum, or total utility, even though it probably doesn’t have the highest acquisition utility.)
Now that you are primed with this lesson, let me ask you a hypothetical question: What would you do if you got a coupon that would give you any drink at Starbucks for free? If you answered this, you’ve likely missed the point of the above discussion:
Apparently that is a sexagintuple vanilla bean mocha Frappuccino, and it has a regular price of $54.75. (The container for said drink, in case you were wondering, is a vase that the customer brought from home.) I am very tempted to think that this beverage is the equivalent of the king-size quilt, since what person in his right mind actually finds this beverage to be coincident with rational optimal consumption, even when taking cost out of the picture? That said, I am willing to reconsider my judgment, given the subsequent news that the customer actually drank the whole thing…eventually. In related news, let’s discuss how this beverage and gout medication are likely to be complementary goods.