Evaluation
It is fairly obvious that proximity will be an important factor in the formation of relationships because proximity determines who you are likely to meet.
Attitude similarity
One of the factors determining interpersonal attraction is attitude similarity. Newcomb (1961) paid students to take part in his study. He first found out the beliefs and attitudes of the students. He then used this information to assign students to rooms. Some students were given a room with someone with similar attitudes and others were paired with someone having very different attitudes. Friendships were much more likely to develop between students who shared the same beliefs and attitudes than between those who did not (58% and 25% respectively).
Bryne et al (1968) found that attitude similarity had much more of an effect on interpersonal attraction when the attitudes were of importance to the individual. They arranged it so that participants seemed to have similar attitudes to each other on either 75% or 25% of the topics. This was done by deliberately faking information about the other person. It was only when similarity was related to the topics of most importance to the participant that it affected attraction.
Evaluation
Werner and Parmalee (1979) argued that it was not attitude similarity that was the important factor. They found that similarity in preference for leisure activities (which are related to attitude similarity) was more important for friendship than attitude similarity. According to Werner and Parmalee ‘those who play together, stay together’.
Demographic similarity
Several studies have considered the effects of demographic variables (e.g. age, sex, social class). It has nearly always been found that those who have similar demographic characteristics are more likely to become friends. For example, Kandel (1978) asked students in secondary school to identify their best friend among the other students. These best friends tended to be of the same age, religion, sex, social class and ethnic background as the students who nominated them. Reasonable similarity in physical attractiveness, attitudes and demographic variables is found in friends, engaged couples and married couples.
Similarity in personality
Are people who have similar personalities more likely to become involved with each other? Or is the reverse true in that opposites attract? Winch (1958) argued for the latter possibility. He claimed that married couples will be happy if they each have complementary needs. For example, if a domineering person marries someone who is submissive, this may allow both of them to fulfil their needs.
Winch found that married couples who were different in personality were happier than those who were similar. However, most of the evidence indicates that similarity of personality is important, and that people tend to be intimately involved with those who are like themselves. Burgess and Wallin (1955) obtained detailed information from 1000 engaged couples, including information about 42 personality characteristics. There was no evidence for the idea that opposites attract. There was significant within couple similarity for 14 personality characteristics (e.g. feeling easily hurt, leader of social events etc.).
Evaluation of the five factors
There is much evidence that the formation of interpersonal relationships depends to a large extent on several kinds of similarity. Why is similarity so important? Rubin (1973) suggested various answers. First, if we like those who are similar to us, there is a reasonable chance that they will like us. Second, communication is easier with people who are similar. Third, similar others ma confirm the rightness of our attitudes and beliefs. Fourth, it makes sense that if we like ourselves, then we will like others who resemble us. Fifth, people who are similar to us are likely to enjoy the same activities.
A great deal of research in this area is rather artificial. For example, the importance of physical attractiveness has sometimes been assessed by showing participants photographs of people they have never met, and asking them to indicate how much they would like to go out with them. Of course, physical attractiveness is going to have an enormous influence on the results when no other relevant information is available. Interpersonal relationships are formed over time as two people begin to know each other better, but the processes involved have rarely been studied in the laboratory.
A further limitation of most research is that individual differences have been largely ignored. Some people attach more importance than others to similarity of physical attractiveness, attitudes and so on, but very little is known about this.
