■ small groups
-complete tasks faster than larger groups.
-make more efficient use of facts.
■ Large groups
-solve problems better than small groups. -Are good for getting diverse input.
-Are more effective in fact-finding.
■ Social loafing
-The tendency for individuals to expend less effort when working collectively than when work individually.
■ Group cohesiveness
- The degreee to which members are attracted to a group and share goals .