The matching hypothesis, also called the matching phenomenon, suggests that people are more likely to build and keep long-term relationships with others who are equally likeable, especially in terms of physical appearance. This idea comes from the field of social psychology and was first introduced in 1966 by American social psychologist Elaine Hatfield and her team.

Couples with different levels of physical attractiveness may stay together if they share other qualities, such as wealth or social status. For example, some men who are wealthy or have high social standing may prefer partners who are younger and more physically attractive. Some women may choose partners with wealth or status even if they are not as physically attractive.

This idea is also similar to some concepts in uncertainty reduction theory, which is part of the study of communication. These concepts include body language, feeling similar to others, liking someone, trying to learn about others, and building closeness. These elements are connected to each other in different ways.

Research

Walster organized an event called the "Computer Match Dance." In this event, 752 students were evaluated for physical attractiveness by four separate judges, as a way to measure how socially desirable they were. Participants were told to complete a questionnaire to help a computer match them based on shared traits. However, instead, they were randomly paired, except that no man was paired with a taller woman. During a break in the dance, participants were asked to rate their dates. Those with higher attractiveness scores were more likely to judge their dates harshly. Additionally, people who were more attractive reported lower satisfaction with their pairings, even when they had similar levels of attractiveness. Both men and women were more satisfied with their dates if their dates were more attractive. Physical attractiveness was found to be the most important factor in enjoying the date and in deciding whether to accept a romantic offer. It was more important than intelligence or personality.

Walster noted that the four judges who rated attractiveness had only brief contact with participants. Longer interactions might have changed their ratings. In a follow-up study, it was found that couples were more likely to continue interacting if they had similar attractiveness ratings.

Walster and Walster later conducted a follow-up to the Computer Match Dance, allowing participants to meet beforehand to discuss their ideal partner qualities. This study had better ecological validity, meaning it was more similar to real-life situations. The result showed that couples with similar levels of physical attractiveness expressed the most liking for each other, supporting the matching hypothesis.

Murstein also found evidence supporting the matching hypothesis. He analyzed photos of 197 couples in different relationship stages (from casual dating to married). Eight judges rated the attractiveness of each person individually, without knowing which photos belonged to the same couple. The judges’ ratings supported the matching hypothesis.

In the first round of the study, self-perception and how participants viewed their partners were included. However, these were later removed because people often rated themselves and their partners too highly.

Huston argued that the matching hypothesis might not be about finding matches but about avoiding rejection. He suggested that people choose partners with similar attractiveness to avoid being rejected by someone more attractive. He tested this by showing participants photos of people who had already agreed to be their partners. Participants usually chose the most attractive person, but this study had poor ecological validity because real-life relationships are uncertain.

White studied 123 dating couples at UCLA. He found that couples with similar levels of physical attractiveness reported greater happiness and deeper feelings of love.

The study also showed that some people, especially men, view relationships like a marketplace. If a relationship is weak, a person might value it less if they have many attractive friends of the opposite sex. They might see more options. If a relationship is strong, they might value it more because they are choosing to stay in the relationship despite other opportunities.

Brown supported the matching hypothesis but believed it results from learned expectations about what is "fitting." People adjust their expectations based on what they think they can offer others, not just from fear of rejection.

Garcia and Khersonsky studied how people view matching and non-matching couples. Participants saw photos of couples who matched or did not match in attractiveness and completed a questionnaire. They rated how satisfied the couples seemed, their potential marital happiness, the likelihood of breakup, and how likely they would be good parents. Results showed that couples with similar attractiveness were rated as more satisfied than couples where one partner was more attractive. Unattractive men in non-matching couples were also rated as more satisfied than attractive women in the same situation. Attractive women in matching couples were rated as more satisfied than in non-matching ones.

Shaw Taylor studied the matching hypothesis in online dating. He measured the attractiveness of 60 men and 60 women and monitored their interactions. People tended to contact others who were more attractive than themselves but were more likely to receive replies if their attractiveness levels were similar. This study supported the matching hypothesis but suggested it was not intentional.

Further evidence supporting the matching hypothesis was found by:
• Berscheid and Dion (1974)
• Berscheid and Walster et al. (1974)

Quotations

• Price and Vandenberg said that "the matching phenomenon [of physical attractiveness between marriage partners] is stable within and across generations."
• "Love is often a fair exchange between two people who receive the most they can expect, based on each person's worth in the 'personality market.'" — Erich Fromm