Date of Graduation


Document Type


Degree Name

Doctor of Philosophy in Psychology (PhD)

Degree Level



Psychological Science


David A. Schroeder

Committee Member

Denise R. Beike

Second Committee Member

Scott Eidelman


Psychology, Certainty, Cooperation, Group voice, Justice, Risk aversion, Voice


The purpose of the current investigations was to examine the effects of the amount of voice one is given during decision-making on group behaviors. In particular, across two studies, participants were members of groups that needed to make a decision. In these situations, participants were provided varying degrees of voice during a decision-making process. Depending on the study, participants were either given a direct voice (Personal Voice), an indirect voice (Group Voice), a direct voice and an indirect voice (Composite Voice), or were not allowed a voice (No Voice). The results of Study 1 found that having Personal Voice or Composite Voice is related to increased perceptions of control, trust, and certainty, and is related to more predicted effort put forth for the group. In contrast, having Group Voice or No Voice was shown to be related to low levels of control, trust, and certainty. Furthermore, Group Voice was related to less predicted effort given toward achieving group goals. The findings of Study 1 suggest that the reason more voice is related to more positive group effort is because of how trust in the decision-maker is positively related to being more certain of what that decision-maker will do, which in turn predicts more certainty of how the decision will affect one's self as a member of the group in the future. The results of Study 2 found that Personal Voice was related to increased perceptions of voice and certainty, with Group Voice and No Voice related to low levels of certainty. Interestingly, Study 2 found that more voice given to group members was related to less behavioral output on behalf of the group. The relationship between having more voice and less effort was explained by perceptions of certainty. The findings of the current research suggest that groups must take care to ensure their members are treated in a fair manner because there are both benefits and limitations to providing members a voice during decision-making.