[EM] Score Voting and Approval Voting not practically substantially different from Plurality?

Benjamin Grant panjakrejn at gmail.com
Mon Jun 24 11:17:14 PDT 2013

On Mon, Jun 24, 2013 at 1:28 PM, Kathy Dopp <kathy.dopp at gmail.com> wrote:

> Please forward to the appropriate list for me.  Thank you.
> From: electionscience at googlegroups.com
>> [mailto:electionscience at googlegroups.com] On Behalf Of Benjamin Grant
>> Sent: Monday, June 24, 2013 11:40 AM
>> On Mon, Jun 24, 2013 at 11:08 AM, Stephen Unger <unger at cs.columbia.edu
>> <mailto:unger at cs.columbia.edu> > wrote:
>>   If you cast votes (approve or give high scores to)
>> only for parties that might win the current election, then we will be
>> stuck forever with the existing 2-party scam.
> Yes. But the point of approval or score voting is voters do not have to do
> that in order to keep their least favorite from winning.

I understand that is it's goal, but I seem to have pointed out that it
still does that.  Aparently, not well, though.

>  And under Score/Approval/Plurality voting systems, there would be three
>> phases a party might go through:
>> A) unpopular enough not to be a spoiler
>> B) popular enough to be a spoiler, but not popular enough to win
>> C) popular enough to win often (>25% of the time, for example.)
> Those options apply to plurality and IRV, not to approval or score voting
> where a voter's 2nd choice vote cannot cause his least favorite to win.

Except when it does? I know that the party line is that "Approval and Score
Voting cannot cause your least favorite to winner", but that's untrue if
Nader being Abe's (our voter's) preference over Gore causes him to give
less than 100 to Gore - that *can* cause Bush to win.  The only way to be
sure that he has done everything to prevent Bush from winning (if that is
his highest priority in a Nader/Gore/Bush election) is to make sure to
score the person most likely to beat Bush as high as possible.  Therefore
he *must* strategically score Gore a 100, Therefore Score/Range voting
devolves into Approval voting.

So let's examine Approval voting, since that is what we are left with.  If
we do an Approval voting system with Gore/Nader/Bush, assuming that Abe's
first priority is to stop Bush and his next priority (a distant second,
considering how opposed he is to Bush) is to support Nader over Gore.

Well, now he cannot do that. He can support Nader *and* Gore, be he cannot
support Nader *over* Gore without risking a greater chance of a Bush
victory. And in our example (as in real life) Gore has much more support
than Nader.

This means that If he Approval votes for BOTH of them, it is unlikely that
his vote for Nader will accomplish anything.
If he votes for ONLY Nader, he has a better chance for Nader to beat Gore,
but a much worse chance for stopping a Bush victory.

And, this is the poison pill: Let's say that election after election people
see that more and more people are voting for Nader,although he is not
winning.  Thinking optimistically (as some people like to) that this might
be the year that Nader could take it all, they put all their money on Nader
- they vote Nader, but *not* Gore. The result? Gore's numbers drop, Nader's
numbers rise a little, but Bush still get's the most!

This seems almost worse than plurality, in a way, because at least with
plurality we all knew and admitted that we need to vote against the spoiler
effect, but Approval voting may actually suffer from it just as much while
not as obviously - meaning people may vote against there interests more by
not seeing that.

Make sense?

> On your way to C, you are going to have a LOT of B, and you may never make
>> it to C, especially if people get burned voting for the emerging party by
>> getting their least preferred candidate.
>> Speaking re. plurality or IRV still.


>> The only way to build a strong new party in reality, as far as I can see,
>> is
>> to have a voting system that does not penalize you into getting your least
>> favored choice by voting for your most favored one.
> Yes.  Agreed.


> Second of all, it seems to me that the less divergence there is between
>> strategic and sincere voting, the more beneficial qualities the voting
>> system has, such as:
>> -we can worry less about the spoiler effect, which promotes more than
>> just 2
>> parties
>> -we can worry less that people are accidentally voting against their
>> interests
>> -we can have fewer debates about whether people have an obligation to vote
>> strategically or sincerely
>> This would seem to be a good thing.
> Ideally, but practically we may have to continue to vote for all
> candidates other than our least favorates.

Again, huh? "we may have to continue to vote for all candidates other than
our least favorates"? When we we NOT vote for candidates other than our
least favorites? You seem to be suggesting that I want voters to vote for
their least favorite candidates?

>> *         Intelligent use of Score Voting becomes Approval Voting, and the
>> harm in unwise use of Score voting means that Approval Voting is superior
>> to
>> (and simpler than) Score voting pragmatically.
> I agree.

OK, so at least we agree that Score Voting is little more than a stop on
the way to Approval voting.

>> *         Approval Voting tends to result in irrelevant approval votes
>> being
>> given to weak candidates - which is pointless, or slightly stronger (but
>> still losing) candidates can once again present a spoiler effect where a
>> person's least preferred choice is elected because they cast their
>> approval
>> only toward their most preferred choice, who was nowhere near supported
>> enough to stop their least preferred choice.
> First, why should anyone care if some votes turn out to be "irrelevant"
> according to your definition?  Second, if someone uses approval voting like
> plurality  byvoting for their true favorite without  also voting for their
> most likely favorite candidate to win, then they are accepting that they
> might spoil the chances of their other favorite(s).  Neither of these
> arguments is a logically coherent reason for favoring plurality over
> approval voting.

Well the above example illustrates that.  Plus, some of us may find that a
system in which people must accept that voting sincerely is not in their
best interest is not as good a system as one in which that is less likely.
 And the only point I was making is for the 3rd party supporter (when there
are two stronger parties), there is no practical difference between
Approval and Plurality - either way, if he votes smart, he helps Gore beat
Bush, and Nader doesn't win.  If he votes less smart, he can even
regrettably (from his point of view) help Bush beat Gore by only Approving

So the fact that he is penalized by support Nader *over* Gore by getting
his last choice Bush is something that I thought Approval (and by
extension, Range/Score) were supposed to fix.

Since this isn't fixed, tell me what the benefit of Approval is in the real
world over Plurality?  I want to be CLEAR about this, so please let me: I
am not asking how the what supporters of Approval voting promise will
happen, nor what Approval voting's creators intentions are - I am ONLY
asking about pragmatic and real-world RESULTS.

It is easy I think to see that with the Gore/Nader/Bush example, a Nader
supporter has to choose between stopping Bush and voting his true
preference.  It seems to me that whatever the criterion is named that
covers that, that's an important one to embrace.

Expressing your true preference should never cause your least favored
outcome to happen - and here it sure seems to.

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