Final answer:
The group classification variable that refers to the closeness and intimacy of the group linkages is strength of social tie.
Step-by-step explanation:
The group classification variable that refers to the closeness and intimacy of the group linkages is strength of social tie. This refers to the emotional connection and bond between individuals within a group.
A strong social tie implies a close and intimate relationship within the group, while a weak social tie suggests a more distant and less intimate connection.
For example, in primary groups such as family or close-knit friend circles, the strength of social tie is usually strong, as there is a high level of closeness and intimacy among its members.