Birkmeier, Olga; Käufl, Andreas; Pukelsheim, Friedrich Abstentions in the German Bundesrat and ternary decision rules in weighted voting systems. (English) Zbl 1208.91039 Stat. Decis. 28, No. 1, 1-16 (2011). Summary: Ternary decision rules allowing for abstentions,besides Yea- and Nay-votes, are analyzed. The German Bundesrat serves as a prime example. We show that the decision-making efficiency of the Bundesrat would increase if abstentions were allowed. A general formula for the mean success margin of a ternary decision rule is derived assuming selfdual and permutationally invariant distributions. The ternary Penrose-Banzhaf model is discussed in detail, and the influence probabilities of voters and a ruleś influence sensitivity are evaluated. Cited in 1 Document MSC: 91B12 Voting theory 91F10 History, political science Keywords:decision-making efficiency; Penrose-Banzhaf index; straight majority rule; unanimity rule; voting power PDFBibTeX XMLCite \textit{O. Birkmeier} et al., Stat. Decis. 28, No. 1, 1--16 (2011; Zbl 1208.91039) Full Text: DOI Link