The following variables have been found to be associated with the establishment of a friendship.
Physical Proximity A person who lives near us, or with whom we have regular contact, may become a friend. In apartment buildings, people who live on the same floor are likelier to become friends than people who live on different floors, and the people who live near the mailbox or the stairs have the most friends of all. Our friends tend to be coworkers, classmates, and people we see regularly at the gym or in the elevator.
Frequency The more often we see a person, the more likely this person will become a friend. This, a person we see at work or in class everyday has the potential to be a friend.
Common Interests People who join groups based on a hobby or another interest are likely to make friends with other group members. They know and have an interest in the same information, and this prompts people to enter into conversations and engage in the same activities. For example, hiking clubs, gourmet food sharing groups, and reading groups attract people with a common interest- and friendships emerge from these groups.
Common Demographic Characteristics We tend to make friends most easily with people of the same general background in terms of age, gender, and socioeconomic status. Our shared backgrounds allow for comfort with the other person and a common general approach toward dealing with the world.
Self Disclosure The point at which an interaction moves from acquaintanceship to friendship is when one person starts to talk about his or her own life. Self disclosure has to be mutual and balanced between two people in order for friendship to start. It starts out with the exchange of minimal information and then moves into higher degrees of self disclosure as the friendship develops. If one person does all the talking and the other person has little to say, the balance between the two people is not achieved and a friendship is less likely to occur.
Reciprocity A healthy friendship carries with it a sense of equality between the two people. If you disclose personal information, you expect that the other person will reveal personal information at about the same rate that you do. In fact, we tend to “test” the other person to see if they talk about themselves to the same degree that we have. Reciprocity, however, goes further than self- disclosure. If we do a favor for a friend, we expect the same general behavior in return. If you drive to the group one night, you expect that your friend will drive another night- or at least repay the favor in another way that has equal value (although openly keeping a ledger of favors can doom a friendship). Friends are people who generally do as much for us as we do for them.
Intimacy Once self disclosure and reciprocity have been established in a friendship, the final variable is the ability of the two people to establish an appropriate level of intimacy between them. Intimacy involves emotional expression and ideally includes unconditional support of the other person. That is, we accept the other person without placing value judgments on him or her. A friendship with intimacy also includes trust and loyalty. An intimate friendship is one in which we feel that we can be ourselves. We’ll be valued and accepted just for being who we are. It makes us feel alive and warm. In other words, a good friendship depends less on who the other person is than on how they make us feel.