<div dir="auto">To prioritize simplicity here's my current thinking:<div dir="auto"><br></div><div dir="auto">Gauge pairwise defeat strength with pairwise margins: winning votes minus losing votes.</div><div dir="auto"><br></div><div dir="auto">To summarize:</div><div dir="auto"><br></div><div dir="auto">Initialize a pairwise defeat chain with the defeat having the greatest defeat margin.</div><div dir="auto"><br></div><div dir="auto">Until the head of the chain is uncovered, replace it with the candidate that covers it with the greatest margin of defeat.</div><div dir="auto"><br></div><div dir="auto">Then elect the final head of the chain.</div><div dir="auto"><br></div><div dir="auto">A candidate X is uncovered if it can defeat every challenger Z in two or fewer steps ... i.e. if an uncovered X is defeated by some challenger Z, then there is some intermediate candidate Y that is defeated by X but not defeated by Z. </div><div dir="auto"><br></div><div dir="auto">[or defeats Z but not X]</div><div dir="auto"><br></div><div dir="auto">I doubt that there is any other monotone, clone-independent, Landau efficient method that is easier to understand or tally. </div><div dir="auto"><br></div><div dir="auto">Landau efficient means that it always elects an uncovered candidate. </div><div dir="auto"><span style="font-family:sans-serif">In general, every Smith candidate has a beatpath to every other candidate. Every Landau candidate has a short beatpath to every other candidate. How short? At most two steps.</span><br></div><div dir="auto"><br></div><div dir="auto">So every uncovered candidate is a member of the Smith set ... therefore when the Smith set has only one member it is the one and only uncovered candidate.</div><div dir="auto"><br></div><div dir="auto">Any RCV method that elects a covered candidate X should be sued in court by the supporters of the candidate(s) that cover X.</div><div dir="auto"><br></div><div dir="auto">Part of the court's remedy, besides punitive damages, would have to be a mandate to adopt a Landau efficient method ... which might be the easiest route to getting this method adopted.</div><div dir="auto"><br></div><div dir="auto">Once somebody is familiar with this method, why would they propose some other voting method?</div><div dir="auto"><br></div><div dir="auto">Well, suppose the method turned out to be easy to manipulate ... and that problem could not be fixed by changing the defeat strength gauge ... then we would cheerfully tacharlo.<br></div><div dir="auto"><br></div><div dir="auto">So now, the more people that can test it on their favorite ballot profiles, the better.</div><div dir="auto"><br></div><div dir="auto">In particular, somebody with a computer should try it on all seven of Kevin's standard 3-candidate test cases.</div><div dir="auto"><br></div><div dir="auto">Thanks!</div><div dir="auto"><br></div><div dir="auto">-Forest</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Jan 31, 2023, 6:32 PM Forest Simmons <<a href="mailto:forest.simmons21@gmail.com">forest.simmons21@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="auto">I seem to have lost a draft of a reply ... I won't try to repeat the whole thing ... just that many numerical experiments are in deed needed ... specifically to find the best performing defeat strength measures.<div dir="auto"><br></div><div dir="auto">Here's one worth exploring ...</div><div dir="auto">max(winning Top, losing Bottom)</div><div dir="auto"><br></div><div dir="auto">Here's an example ...</div><div dir="auto"><br></div><div dir="auto">8 A>B (Sincere is A>C)</div><div dir="auto">6 B>C</div><div dir="auto">4 C (Sincere is C>A)</div><div dir="auto"><br></div><div dir="auto">A>B winning top 8, losing bottom 4</div><div dir="auto">B>C winning top 6, losing bottom 8</div><div dir="auto">C>A winning top 4, losing bottom 10</div><div dir="auto"><br></div><div dir="auto">The max strength is 10 for C>A</div><div dir="auto"><br></div><div dir="auto">This restores the win to the sincere CW.</div><div dir="auto"><br></div><div dir="auto">I like it!</div><div dir="auto"><br></div><div dir="auto">This rule seems to be the best expedient against Dark Horse winners that some methods elect when the middle range category is the vague, other/default category ... in this case the outer categories of definite approval (equal Top) and definite disapproval (equal Bottom) leave the middle category as the vague "other" default ... a dark horse red flag for the method inventor. </div><div dir="auto"><br></div><div dir="auto">Our remedy is the defeat strength's prominent usage of the max value of the two definite categories as a guard against an unknown nobody winning by default.</div><div dir="auto"><br></div><div dir="auto">-Forest</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Jan 31, 2023, 4:16 AM Kristofer Munsterhjelm <<a href="mailto:km_elmet@t-online.de" target="_blank" rel="noreferrer">km_elmet@t-online.de</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On 1/26/23 21:53, Forest Simmons wrote:<br>
<br>
> [Again, we used the fact that all candidates are uncovered ... which <br>
> makes the initial chain head the winner. This helps explain Krisyofer's <br>
> original observation that got this whole thing started. So you can see <br>
> why I'm tempted to call this the KKF method!]<br>
> <br>
> What do you think?<br>
<br>
Sounds good! But I'm increasingly feeling that it's hard to understand <br>
the tradeoffs of a method without having a view to their behavior, like <br>
simulations. So if it turns out to be awful in practice, then perhaps <br>
I'll have to retract my statement :-)<br>
<br>
On a broader level, I'm wondering if we should pool our simulators <br>
somehow to not duplciate the effort it takes to implement methods. But <br>
my own main simulator is not the prettiest of code, so I would have to <br>
clean that up first. And then I don't get much further than that!<br>
<br>
-km<br>
</blockquote></div>
</blockquote></div>