[EM] NESD and NESD* properties of a single-winner voting method

[Warren Smith]

Let me clarify my thinking a bit (I hope) behind NESD and NESD*.

NESD stands for "Naive Exaggeration Strategy ==> Duopoly."

NES means the voter strategy of
1) identify the "top two" candidates most likely to win.
2) Exaggerate your (otherwise honest) vote to rank one top
and the other bottom.  (With NESD*, unique-top; with NESD, permitted to be
co-equal top.)    It appears that, in the real world, this is a pretty
close approximation of
what a very large percentage of voters in large well publicized+polled
elections actually do (it does not necessarily always make complete
sense that they do that, but the data indicates they do it anyway).

The D part means: if all (or a very large percentage) of voters
exhibit NES behavior, then
one of the top-two will always win (except in exceedingly unlikely
"perfect-tie" scenarios).
And in fact, the same winner will arise as in strategic plurality
voting, so any system
failing NESD or NESD* can be accused (perhaps not with full
justification, but certainly
with some) of being "equivalent in the real world" to plain plurality
voting, and presumably
leading of historical time to "duopoly" where voters effectively only
get one of two choices every election.  This severely diminishes voter
choice and "democracy" if it happens (versus some system with more
than 2 choices).

It's an interesting property (or two properties) and I think worth
consideration.
You can now ask yourself other interesting questions, like "how can I
design good voting
systems passing NESD or NESD*?" etc.


-- 
Warren D. Smith
http://RangeVoting.org  <-- add your endorsement (by clicking
"endorse" as 1st step)
and
math.temple.edu/~wds/homepage/works.html