Goldilocks principle
（重定向自Goldilocks effect）
![An animation used to study the Goldilocks effect in visual attention of infants](/Images/godic/202501/15/-The-Goldilocks-Effect-Human-Infants-Allocate-Attention-to-Visual-Sequences-That-Are-Neither-Too-pone.0036399.s002.ogv3238.jpg")
The Goldilocks principle states that in a given sample, there may be entities belonging to extremes, but there will always be an entity belonging to the average. Or in other words, in a sample, there will always be a U-shaped distribution. When the effects of the principle are observed, it is known as the Goldilocks effect.