When perusing products in an aisle of a store, we quickly form positive or negative impressions of the value of some products even without all the necessary information (e.g. price, number of items in the package, etc.). This is because our brains have evolved mental approximations such as the affect heuristic (Slovic, Finucane, Peters, & MacGregor, 2007), allowing us to evaluate environmental stimuli rapidly. More specifically, the affect heuristic is an immediate evaluation of the positive or negative valence of stimuli on attributes that are easier to determine. However, this also means that attributes that are more difficult to discern are ignored during this evaluation process. Because the affect heuristic happens so automatically and can save us time on shopping trips, it can have a large unconscious impact on what we choose to purchase.
Studies with people and monkeys show that quality is an attribute that is easier to discern than quantity. In people (Hsee, 1998), participants in a study rated a 24-piece dinnerware set to be of higher value as compared with the same 24-piece set with an additional sixteen pieces of which nine were broken (thus, seven additional pieces intact). Although the latter option quantitatively offered more intact pieces, its evaluation was reduced by the additional items in poor qualitative condition. On the other hand, when the same items were juxtaposed as a choice so that they could be directly compared, the same participants now chose the 40-piece dinnerware set that included broken pieces over the 24-piece set that they originally rated as higher in value.
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Initially, participants preferred Set L over Set H. When juxtaposed as a choice, the participants now chose Set H over Set L
(Hsee, 1998).
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In a similar vein, rhesus monkeys (Kralik, Xu, Knight, Khan, & Levine, 2012) preferred a highly-valued food item alone compared to the same highly-valued food item paired with an additional food item of positive but lower value. Thus, the monkeys were evaluating the choice options based on overall quality while neglecting overall quantity. Given repeated trials, however, the monkeys were no longer biased toward the highly-valued food item in isolation. Therefore, the monkeys’ choices were influenced by experience with the choice options, such that experience allowed the monkeys to consider more attributes, i.e. the quantity and overall value of the obtained food items instead of the average quality of the items alone. These results suggest that the affect heuristic, which may have been conserved through evolution, favored quality over quantity but can yet be overridden during joint evaluations and experience.
How could this affect heuristic affect consumer behavior? Because it appears that we are drawn to quality over quantity in our evaluations and choices, shoppers may unconsciously pay a premium for single or packaged products with a larger proportion of their most desired items over more mixed packages with a larger number of items that may actually offer a better overall deal. To prevent this, shoppers can try placing packaged products side by side to avoid the biasing effects of affect heuristic memories. This will help consumers more objectively take into account important features such as quantity in shopping decisions.
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| a 6-pack of cheetos |
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| A 50 pack of assorted chips, with 10 packs of cheetos.
According to the affect heuristic, a cheetos lover will most likely value this significantly less than the 6-pack of cheetos without other flavors (per pack) even if the other flavors are not aversive.
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