Additive task A task where the inputs of each group member are added together to create the group performance, and the expected performance of the group is the sum of group members’ individual inputs

Adjourning stage When group members prepare for the group to end

Compensatory (or averaging) task A task where the group input is combined such that the performance of the individuals is averaged rather than added

Conjunctive task When the group performance is determined by the ability of the group member who performs most poorly

Criterion task A task where the group can see that there is a clearly correct answer to the problem that is being posed

Devil’s advocate An individual who is given the job of expressing conflicting opinions and forcing the group (in a noncombative way) to fully discuss all the alternatives

Disjunctive task When the group’s performance is determined by the best group member

Divisible task When each of the group members working on the job can do a separate part of the job at the same time

Dominant response The action that we are most likely to emit in any given situation.

Entitativity The perception, either by the group members themselves or by others, that the people together are a group

Entity theorists People who tend to believe that others’ traits are fundamentally stable and incapable of change

Group polarization When, after discussion, the attitudes held by the individual group members become more extreme than they were before the group began discussing the topic

Group process The events that occur while the group is working together on the task

Groupthink When a group that is made up of members who may actually be very competent and thus quite capable of making excellent decisions nevertheless ends up making a poor one as a result of a flawed group process and strong conformity pressures

Illusion of group effectivity The tendency to overvalue the level of productivity of our ingroups

Injunctive norms Rules that specify how group members are expected to behave.

Intellective task A task that involves the ability of the group to make a decision or a judgment

Interdependence A state in which the group members depend on each other for successful performance of the group goals

Judgmental task A task for which there is no clearly correct answer to the problem

Maximizing task A task that involves performance that is measured by how rapidly the group works or how much of a product they are able to make

Mindguard Someone whose job it is to help quash dissent and to increase conformity to the leader’s opinions

Norming stage When the appropriate norms and roles for the group are developed

Not invented here bias When group members overvalue their own group’s ideas and products over those of other groups

Outcome bias A tendency to look at the outcome too much when we evaluate decision making

Performing stage When group members establish a routine and effectively work together

Prescriptive norms Rules which tell the group members what to do

Process gain When groups work better than we would expect, given the individuals who form them

Process loss When groups perform more poorly than we would expect, given the characteristics of the members of the group

Production blocking When only one person can speak at a time, and this can cause people to forget their ideas because they are listening to others, or to miss what others are saying because they are thinking of their own ideas

Proscriptive norms Rules which tell the group members what not to do

Role stress When individuals experience incompatible demands and expectations within or between the roles that they occupy, which often negatively impacts their ability to be successful in those roles

Shared information bias When group members tend to discuss information that they all have access to while ignoring equally important information that is available to only a few of the members

Social facilitation The tendency to perform tasks better or faster in the presence of others

Social group A set of individuals with a shared purpose and who normally share a positive social identity

Social inhibition The tendency to perform tasks more poorly or slower in the presence of others

Social loafing A group process loss that occurs when people do not work as hard in a group as they do when they are alone

Storming stage When group members may attempt to make their own views known, expressing their independence and attempting to persuade the group to accept their ideas

Sunk costs bias When we choose to stay in situations largely because we feel we have put too much effort in to be able to leave them behind

Unitary task A task that has to be done all at once and cannot be divided up