Morewedge and Giblin (2015) Look to Explain the Endowment Effect

Carey K. Morewedge and Colleen E. Giblin, “Explanations of the Endowment Effect: An Integrative Review.” Trends in Cognitive Sciences 19(6): 339-348, June, 2015 [pdf].

• Endowment effects tend to be demonstrated in one of two ways: (1) the “exchange paradigm,” where people who are endowed with a good are less willing to trade it for another good than pre-endowment preferences would suggest; and, (2) differences between the willingness to pay (wtp) for a good by a non-owner and the willingness to accept payment (wta) by an owner – differences which seem to materialize about the time the non-owner becomes an owner. 

• Loss aversion is a standard underlying explanation for the endowment effect; once you own a good (or even expect to), your ownership becomes your reference point, and situations where you no longer own it are evaluated as losses relative to the reference point. 

• The authors look at five underlying mechanisms that are claimed to give rise to loss aversion and endowment effects, and offer a more general framework: “attribute sampling bias.” 

• Buyers and sellers pay attention to reference prices (low for buyers, high for sellers) that will increase their transactional utility. Prices are just one example of how buying and selling activate different cognitive frames that direct attention and recall to different pieces of information. Buyers and sellers do not have the same information readily in mind, so the endowment effect does not arise because they value identical attributes differently. People even have trouble recalling frame-inconsistent information. 

• Psychological ownership raises wta for two reasons: (1) ownership creates a connection between your identity and the good; the better that you feel about yourself, the better you will feel about the good. Losing the good can seem like a threat to your identity. (2) ownership helps you remember good feelings about the good, which otherwise might be harder to access. 

• Their attribute sampling bias explanation resembles the well-known phenomenon where people seek out information that confirms their current beliefs. 

• Sadness tends to reduce or reverse the endowment effect – it creates an implicit interest in changing your circumstances, so non-owners are more willing to acquire a good and owners are more willing to sell a good. But most frames in the exchange setting (other than sadness) tend to bias people towards maintaining the status quo. 

• People are eager to trade away a “bad”, which can’t be explained by some other approaches to endowment effects, where whatever you own you value more highly. Further, endowment effects are higher for those goods (like environmental goods) that have vague attributes, giving more room for attention to a biased sample of attributes to take effect.