Group Influence on Behavior

*Social Facilitation*

• Improved performance of tasks in the presence of others.
• occurs with simple or well learned tasks
• not with tasks that are difficult or not yet mastered

*Yerkes-Dodson Law*

• There is an optional level of  for the best performance of any task easy task---relatively high 
• difficult tasks---low arousal
• other tasks---moderate level

*Social Loafing*

• That tendency for people in a group to exert less effort when pooling efforts toward a common goal than if they were individually accountable. 

*Deindividuation* 

• The loss of self awareness and self- restraint occurring in group situations that foster arousal and anonymity

*Group Polarization*

• The concept that a group's attitude s one of extremes and rarely moderate

*Group think*

• The mode of thinking that occurs hen the desire for harmony in a decision making group overrides common sense.

* Self- Fulfilling Prophecies

• Occurs whenever a person's belief about others leads one to act in ways that induce the others to appear to confirm the belief.