Kolmen strategian äänestyspelien ominaisuuksia

Authors

• Antti Pajala

Abstract

In contrast to voting power analyses applying simple voting games (SVG) I examine ternary voting games (TVG). In TVGs voter abstention is permitted as a third distinct voting option. I apply the expected power of winning (EPW) together with the standardized (sBz) and absolute (aBz) Banzhaf indices to compute voting power. I present an SVG example and compare it to two TVGs: In addition to the EPW analysis presented in the literature, I take the analysis further and demonstrate how the swings, and hence, voting power for the sBz and aBz are determined under TVGs in cases where the voting rule is either a relative majority from the votes cast or a fixed majority from all voters all votes. I show that the EPW and aBz indices are closely related in both SVG and TVG contexts. The computation results show that the index values vary among the SVG and the TVG examples. As a special case and in contrast to an SVG dictator game it appears that a TVG dictator does not necessarily have all the voting power, nor is the voting power of the other voters zero. Last, I present an analogue between the SVG and TVG versions of the Coleman collectivity index.