The story
After the phrase big fish in a small pond. The effect was introduced by Herbert W. Marsh and John W. Parker in 1984.
Etymology from Wiktionary, CC BY-SA 4.0.
big-fish-little-pond effect
Today it means: The tendency of individuals to compare their own self-concept with their peers, which suggests that equally capable individuals have higher self-concepts when in a less capable group than in a more capable group. Full definition →