[1] In a 1998 study, Hsee, a professor at the Graduate School of Business of The University of Chicago, discovered a less-is-better effect in three contexts:[1] (2) an overfilled ice cream serving with 7 oz of ice cream was valued more than an underfilled serving with 8 oz of ice cream; Hsee noted that the less-is-better effect was observed "only when the options were evaluated separately, and reversed itself when the options were juxtaposed.” Hsee explained these seemingly counterintuitive results “in terms of the evaluability hypothesis, which states that separate evaluations of objects are often influenced by attributes that are easy to evaluate rather than by those that are important.
[1] In one study involving 83 students from a large university in the American Midwest, participants were asked to fill out a questionnaire.
Therefore, "if gift givers want their gift recipients to perceive them as generous, it is better for them to give a high-value item from a low-value product category (e.g. a $45 scarf) rather than a low-value item from a high-value product category (e.g. a $55 coat).
Evidence has shown that it manifests itself only when the options are evaluated individually; it disappears when they are assessed jointly.
[1] "If the options are put right next to each other, the effect disappears, as people see the true value of both," states one source.
[1] An additional practice can be used for people who want to lose weight: serving their meal on a smaller plate.