[EM] Re: Is strategic voting a bad thing, really?

[Rob LeGrand]

Bill Clark wrote:
> My immediate intuition was that while something like DSV+Plurality would
> still result in two parties being dominant, *which* two parties those
> were might be more subject to fluctuation, than with standard plurality.

Yes, there would be more fluctuation.  Plurality DSV would effectively
allow jumps between equilibria instead of keeping us mired in one two-party
"equilibrium" as continuous polling and plain plurality do.  In particular,
if the sincere preferences are

45:Reagan>Anderson>Carter	
20:Anderson>Carter>Reagan	
35:Carter>Anderson>Reagan

then there are three plurality equilibria (according to Philip Straffin in
Game Theory and Strategy); one elects Carter with Reagan as the runner-up
and the other two elect Anderson.  Unfortunately, the Carter/Reagan
equilibrium is the one most likely to be found by plurality DSV.  Approval
DSV is much more likely to find an Anderson equilibrium, especially given
the best approval strategies.

> I think there's some argument to be made that the USA should currently
> have a two-party duopoly consisting of Greens/Republicans or
> Democrats/Libertarians (or even Greens/Libertarians.)

I guess Libertarians/Republicans is too much to hope for . . .

> I'd be interested in reading more about that, when your work reaches a
> point you're happy with.  I trust you'll share with the list when you're
> ready? :)

Oh, absolutely.  I'll announce all publications here.

=====
Rob LeGrand, psephologist
rob at approvalvoting.org
Citizens for Approval Voting
http://www.approvalvoting.org/

__________________________________
Do you Yahoo!?
Yahoo! Small Business $15K Web Design Giveaway 
http://promotions.yahoo.com/design_giveaway/