[EM] New VSE & nonmanipulability numbers

[Kristofer Munsterhjelm]

On 05/12/2014 06:03 AM, Jameson Quinn wrote:
> As I've mentioned several times, I've been working on some new voting
> system simulations, akin to Warren Smith's Bayesian Regret work. I have
> some new and, I think, interesting results now. I'll explain my full
> methodology later, but first, here's an old graph I had which I've
> updated using my results:
>
> Imágenes integradas 1
> * These systems (Borda and IRV) have flaws which do not show up in the
> graph. Also, Random Ballot should be more than twice as far to the left
> of the Y axis as I have put it.
> ** These systems (SODA, Approval w/Runoff, and Plurality w/Runoff) are
> in principle possible to simulate, but I haven't finished doing so yet,
> so the numbers used here are educated guesses using my work so far.

Have you tried the Condorcet-IRV hybrids that Green-Armytage tested? 
According to his working paper ( 
http://inside.bard.edu/~armytage/strategy-utility.pdf ), prefixing 
Condorcet to a rule doesn't seem to affect manipulablility much. It also 
seems to show cardinal pairwise as more resistant to strategy than 
ordinary minimax.

I'd also suggest trying Random Pair to see how it fares compared to 
Random Ballot (as far as strategy-proof methods go). If you'd like to be 
thorough, you could also try combinations of Random Pair (e.g. x * RP + 
y * RB) since these, AFAIK, are also strategy-proof.