##  [Banzhaf Power Index](/banzhaf-power-index) 

  ##  [Banzhaf Power Index](https://social.quantumdictionary.io/banzhaf-power-index-0) 

  

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**Social Sciences Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A quantitative measure of a voter's a priori power in a binary voting body with weighted votes, defined as the proportion (or normalized count) of all possible coalitions in which that voter is pivotal—i.e., changing that voter's yes/no position changes the outcome—under the assumptions that coalitions are evaluated only by whether they meet a fixed quota and that all coalitions are equally likely