[EM] IRV vs Plurality

[Abd ul-Rahman Lomax]

At 01:19 PM 1/11/2010, Dave Ketchum wrote:
>Plurality does that only when you vote for one who has a possibility
>of winning.  Sometimes doing that prevents voting for the one you
>prefer but expect to lose.

There is an aspect of this which is often overlooked, amidst 
assumptions about what voters prefer, and the 2000 presidential 
elector election in Florida showed this, in fact.

Everybody assumes that the Nader voters preferred Gore. But our study 
of Range voting, if it's shown us anything, it should show us that 
preference strength matters.

There is something that is quite obvious: the Nader voters didn't 
have enough preference strength between Gore and Bush to 
counterbalance their desire to express their preference for Nader.

Gore did not "own" those votes. I know of another interest group that 
also, I'm sure, shifted that election (it was so close that this 
could be said about many groups.) Muslims. There was a political 
action group that became active in 2000, for that election, and it 
approached the Gore campaign and asked to meet. They were blown off. 
The Bush campaign agreed to meet with them, and did. Now, which 
candidate did they support?

Lucky guess.

And it is a near certainty that this shifted enough votes to cause 
Gore to lose.

Preference strength. Very important to consider, much about voting 
systems makes no sense if all we think about is raw preference. Sure, 
in a head-on election, no other candidates, Gore would probably have 
won. Or not. Because the Nader message was that the choice between 
Gore and Bush did not matter. The Nader votes presumably agreed with 
that, and so we can't assume that they were "prevented from voting 
for the one they preferred." They did so vote, and the result was 
presumably not unsatisfactory to them, not immediately anyway. Later, 
they found out whether Nader was right or not.

What would make us think that, with Range Voting, these voters 
wouldn't have bottom ranked both Gore and Bush?

Well, here's what: voters don't believe everything that their 
candidates tell them! But, still, each one of them made that choice 
on election day, as to which benefit was more important: showing 
support for Nader or the Green Party, or electing the preferred frontrunner.