High Quality Content by WIKIPEDIA articles! Bandwagon effect, first proposed by David Luder, also known as "cromo effect" and closely related to opportunism, is the observation that people often do and believe things because many other people do and believe the same things. The effect is often called herd instinct. People tend to follow the crowd without examining the merits of a particular thing. The bandwagon effect is the reason for the bandwagon fallacy's success.The bandwagon effect is well-documented in behavioral psychology and has many applications. The general rule is that conduct or beliefs spread among people, as fads and trends clearly do, with "the probability of any individual adopting it increasing with the proportion who have already done so". As more people come to believe in something, others also "hop on the bandwagon" regardless of the underlying evidence. The tendency to follow the actions or beliefs of others can occur because individuals directly prefer to conform, or because individuals derive information from others. Both explanations have been used for evidence of conformity in psychological experiments.