Unfortunately, Bucklin systems fail that one too. However, it passes "Adding one more ballot that votes X as highest preference, and a ballot (either the same one or a second one) that votes Y as lowest preference, should never change the winner from X to Y". You can change "highest" to "above the winning median" and "lowest" to "below the second-place median" and this passage still holds, although then the criterion is meaningless for a non-median system.
Basically, Bucklin systems can fail participation if the added ballot(s) rate both X and Y above, or both below, the winning median; it cannot fail if the added ballot(s) span the median with X and Y. Thus if voters know beforehand the winning median and the two frontrunners, they can make sure that their ballot will not violate participation. And in a partisan environment with two clear frontrunners, most people's ballots will honestly meet that criterion without even a need for strategy. Jameson 2013/6/17 Benjamin Grant <[email protected]> > OK, let’s assume that as defined, Bucklin fails Participation. **** > > ** ** > > Let me specify a new criteria, which already either has its own name that > I do not know, or which I can call Prime Participation:**** > > ** ** > > “*Adding one or more ballots that vote X as a highest preference should > never change the winner from X to Y*”**** > > ** ** > > In other words, expressing a first place/greatest magnitude preference for > X, if X was already winning, cannot make X not win.**** > > ** ** > > This may be another one so basic that few or maybe no real voting systems > fail it?**** > > ** ** > > -Benn Grant**** > > eFix Computer Consulting**** > > [email protected]**** > > 603.283.6601**** > > ** ** >
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