What stood out to me in this chapter is the discussion about group sizing. As a manager, determining group size is essential to whatever objective you are trying to accomplish. A meta-analysis of eight studies showed: "as group size increased, group leaders tended to become more directive, and group member satisfaction tended to decline slightly" (Kreitner 285).
In a laboratory simulation of group behavior, Bottger and Yetton discovered that to maxamize decision quality, groups should be comprised of no more than 5 members. For objectives other than decision-making, larger groups may prove to be more useful. Although group size is ultimately up to the manager, it is recommended that odd numbered groups are more effective in decision making. Group size can determine the overall performance at hand.
I find this particularly true in the groups I have worked with in the past. The smaller, more intimate groups are usually more straight-forward. The larger groups are more useful in discussions because there are many opinions and perceptive offered.
Source: Yetton, Philip, and Preston Bottger. "The Relationships among Group Size, Member Ability, Social Decision Schemes, and Performance." Organizational Behavior & Human Performance 32.2 (1983): 145-159. Academic Search Complete. EBSCO. Web. 27 Feb. 2010.