“intimacy” is used to measure the strength of a tie. The greater the intimacy, the stronger the tie in a relationship between two entities. For instance, assume that the intimacy level is six between entities 1 and 5, and is three between entities 1 and 16. Then, it can be said that the relationship between entities 1 and 5 is stronger than between entities 1 and 16, even if the values of a1,5 and a1,16 are both one.