Psychologist: In our study, participants who were offered the opportunity to purchase a coffee mug were not willing to pay more than $5.
Given that ...
People in the study were not willing to pay more than $5 for a certain coffee mug.
Why is it that ...
If they were given that type of mug and asked to sell it, most of them wanted more than $5 for it.
Evaluate / Goal
We need a way to explain why the mug only seems to be worth "max $5" when they're considering buying it, but seems to be worth "over $5" when they're considering selling it.
The correct answer should point to a distinction about how we think about the value of things we might buy vs. how we think about the value of things we might sell.