The halo effect is a type of cognitive bias where an overall impression of a person or thing positively influences evaluations of that person or thing's specific traits or characteristics.
The term "halo effect" was coined by psychologist Edward Thorndike in 1920, who observed that military officers tended to rate their subordinates' positive traits higher if they found them physically attractive, even without direct knowledge of their other qualities.
It can work both positively and negatively - if you have a favorable impression of something, you'll tend to judge its other aspects more positively, and vice versa. This is sometimes called the "horn effect" when the bias is negative.
The halo effect is thought to be an evolutionary adaptation that allows us to make quick judgments based on limited information. It can influence perceptions in many areas, including education, the workplace, marketing, and the legal system.
companies often try to leverage the halo effect by focusing marketing efforts on their most successful "flagship" products, hoping the positive perception will extend to their other offerings. Celebrity endorsements are another way to take advantage of the halo effect.
However, the halo effect can also be a double-edged sword - a single negative experience with a highly regarded brand can severely damage its reputation and customer loyalty. The classic example is the failure of "New Coke" in the 1980s.
In summary, the halo effect is a well-documented cognitive bias that can have significant real-world impacts, both positive and negative, on how we perceive people, products, and organizations. Understanding and accounting for this effect is important in many domains.