Bandwagon effect

The bandwagon effect is a phenomenon whereby the rate of uptake of beliefs, ideas, fads and trends increases the more that they have already been adopted by others. In other words, the bandwagon effect is characterized by the probability of individual adoption increasing with respect to 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. For example, social pressure has been used to explain Asch's conformity experiments, and information has been used to explain Sherif's autokinetic experiment.

According to this concept, the increasing popularity of a product or phenomenon encourages more people to "get on the bandwagon", too. The bandwagon effect explains why there are fashion trends.

When individuals make rational choices based on the information they receive from others, economists have proposed that information cascades can quickly form in which people decide to ignore their personal information signals and follow the behavior of others. Cascades explain why behavior is fragile—people understand that they are based on very limited information. As a result, fads form easily but are also easily dislodged. Such informational effects have been used to explain political bandwagons.

The definition of a bandwagon is a wagon which carries a band during the course of a parade, circus or other entertainment event. The phrase "jump on the bandwagon" first appeared in American politics in 1848 when Dan Rice, a famous and popular circus clown of the time, used his bandwagon and its music to gain attention for his political campaign appearances. As his campaign became more successful, other politicians strove for a seat on the bandwagon, hoping to be associated with his success. Later, during the time of William Jennings Bryan's 1900 presidential campaign, bandwagons had become standard in campaigns, and "jump on the bandwagon" was used as a derogatory term, implying that people were associating themselves with the success without considering that with which they associated themselves.

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