<div dir="ltr"><p>--- En date de?: Mer 15.10.08, Greg Nisbet <<a href="mailto:gregory.nisbet@gmail.com" target="_blank">gregory.nisbet@gmail.com</a>> a ?crit?:<br>> On the topic of whether there is a method that<br>
> satisfies both<br>> Condorcet and FBC.</p>
<p>There is not. I believe I have demonstrated this in the past, by modifying<br>a Woodall proof that shows Condorcet to be incompatible with LNHarm.</p>
<p>> <a href="http://osdir.com/ml/politics.election-methods/2002-11/msg00020.html" target="_blank">http://osdir.com/ml/politics.election-methods/2002-11/msg00020.html</a><br>> claims<br>> that any majority method will violate FBC.</p>
<div>Note the term *strong* FBC. When FBC is mentioned usually only the weak<br>form is discussed because the strong form is almost impossible to satisfy.</div>
<div> </div>
<div>=what is strong FBC, no incentive to make equal either? Which methods do satisfy strong FBC? I saw this article about a variant of ER-Bucklin that appear to satisfy it, but I couldn't follow it.</div>
<p>> Think of it this<br>> way, any<br>> majority method without equal rankings will always<br>> encourage betrayal so<br>> that a compromise candidate will get the majoirty thereby<br>> sparing you<br>
> potenial loss.</p>
<p>Yes.</p>
<p>> Anything with equal rankings cannot be a<br>> majority method b/c<br>> simultaneous majorities will form and only one will win,<br>> hence allowing a<br>> candidate with a "majority" to in fact lose.</p>
<div>This is avoided by defining the majority criterion to refer to strict<br>first preferences.</div>
<div> </div>
<div>=There are three possible ways to handle "indecisive" voters like this.</div>
<div>1) Ignore them entirely for the purposes of majority</div>
<div>2) Give 1/n to each n candidates that share the first position</div>
<div>3) Do not have them count for any particular candidate, but still count them in the sense that the total against which majority is tested is incremented.</div>
<div> </div>
<div>Example</div>
<div> </div>
<div>3: A>C</div>
<div>2: B>C</div>
<div>16: A=B>C</div>
<div> </div>
<div>Under definition 1 A has a majority 3/5</div>
<div>Under definition 2 A has a majoirty 3 + 8 = 11/21</div>
<div>Under definition 3 A does not have a majority 3/21</div>
<div> </div>
<div> </div></div>