Cheerleader effect

The cheerleader effect, also known as the group attractiveness effect is the cognitive bias which causes people to think individuals are more attractive when they are in a group. The term was coined in 2008 during the How I Met Your Mother episode “Not a Father's Day”, and has been backed up by clinical research by Drew Walker and Edward Vul. The effect occurs because of the brain’s tendency to calculate the average properties of an object when viewing a group.