[EM] Cloneproofing Random Pair and Random Candidate?

[Abd ul-Rahman Lomax]

At 01:54 PM 4/4/2013, Jameson Quinn wrote:

>Hay voting seems to have been invented to encourage the expression 
>of sincere utilities, as distinct from von Neumann-Morgenstern 
>utilities, and there is a whole practically knee-jerk assumption in 
>voting system theory that "strategy" is "bad."
>
>You've made that assertion, that people are looking for low-strategy 
>methods only out of an inherent aversion to strategy, before; and I 
>disagree. There are several problems people could have with 
>strategy, and different people (theorists) focus on different ones:
>1. Some say it's inherently bad because it's dishonest. (I don't care).

Right. However, before Brams proposed Approval, "strategic voting" 
meant reversing preferences, and Brams proclaimed Approval as 
"strategy-free." So a *different meaning* was invented so that 
Approval voting could be asserted to be "vulnerable" to strategic 
voting. The argument went like this. Supposedly a voter *really* 
approves of both A and B, but wants A to win, so the voter 
"strategically" bullet votes for A, the dishonest, greedy thing that 
he is. The argument assumes that there is such a thing as absolute 
approval. In fact, approval, the ordinary process in life, depends on 
context. What I would approve of in one context I would be 
disappointed with in another. It depends on my expectations. And 
"expectations" are strategic considerations, i.e., what I think I can 
get. I'll vote to maximize my expected return, and this is what we 
actually want voters to do in Approval. But there are also other 
considerations. If the voter bullet votes, the voter fails to 
participate in the other elections.

Approval can be a difficult decision. Bucklin makes it somewhat 
easier, but there is still the ultimate approval (i.e., in the lowest 
approved rank). Runoff Bucklin can make it even easier, there will be 
a little more tendency to bullet vote, unless voters want to avoid 
the burden of a runoff. And they can make the choice of whether or 
not to vote in a runoff later. Depends on how much they care!

>2. Widespread strategy can have a disastrous impact on utility/BR. 
>(Think Borda, where this phenomenon is pretty well-documented, at 
>least anecdotally.)

Uh, strategic voting in Borda involves preference reversal. That's a 
different animal. A system that rewards preference *reversal* is a poor system.

(Borda becomes an excellent system if equal ranking is allowed, and 
empty ranks. Essentially, it's Range.)

No, the kind of "strategy" I'm talking about is adjusting *preference 
strength expression,* that's all. In the extreme, down to zero. *Not* 
preference reversal as in Borda.

>2a. If different factions have different inclination or capacity for 
>strategy (for instance, due a take-no-prisoners attitude or better 
>access to polls) it could lead to "unfairness". This would impact 
>legitimacy as well as utility/BR, and the mere whiff of this could 
>be enough to cause a system to be repealed.

Uh, intelligence and knowledge are rewarded? Quick! Who are these 
people so we can stone them!

No, this is basic. If a voter has clear knowledge of how others will 
vote with any system, they can cast a maximally effective vote. The 
easiest way to understand this is to consider that the knowledge is 
so complete that it is as if they are the last voter, and they know 
the results so far. So their vote is either useless (and they might 
not even bother) or their vote can change the results the way they want.

If a system is repealed because knowledgeable voters can vote more 
effectively, and because this is true for every system worth 
considering, to some degree, this could always be alleged (providing 
a "whiff" of suspicion) and thus the best system could be shot down. 
Certainly Range Voting provides greater expected utility for a more 
effective vote, in terms of how preference strength is expressed. 
*However*, any "unfairness" to voters with lesser knowledge is simply 
a matter of them being politically naive. And are we attempting to 
even out the power between those who know the situation and those who 
do not? If voters don't know the situation, they probably have little 
clear knowledge of the *candidates*. A modest disempowerment of these 
people is not a bad thing. They can remedy it, easily. And if they 
don't care enough to do that, *Bayesian regret would suggest that 
some loss of effective power for their vote will improve results.*

By the way, this position is not elitist. That could be me who 
doesn't understand the situation. Some people take a great interest 
in politics, others are much more passive. Neither of these is wrong 
or bad. Turnout already exerts a major push in the direction I'm talking about.

However, a situation where *reversal* of a vote produces a 
significantly improved result for the voter so reversing it, 
represents a system failure. It shouldn't happen, and good systems 
don't encourage this. Basically, a naive voter can vote, in Range, 
just what they think, assuming that other voters will think like 
them, more or less, and the improvement by adjusting these voter for 
strategic effectiveness is small, *unless their knowledge level is 
extremely high;* otherwise there is too much noise in the system to 
truly cast a vote with serious improvement, under Range.

>3. Strategy is a cognitive burden on voters.

Yes. However, for Range and Range-like methods, the burden is small, 
unless the voter wants to extract the very last iota of value out of 
the election -- in which case it can become impossible.

>You seem to be saying that 1 is the only possible reason, but I 
>weight reasons 2 and 2a heavily, and 1 almost not at all.

Jameson, I'd ask you to consider that what I wrote was not aimed at 
you, but was a general comment about discussion of strategy in voting 
systems. I think you have missed much of my point, imagining my view 
to be rigid and narrow. I'd ask you to consider, in particular, what 
I wrote about the reception of Approval Voting, and the historical 
arguments about strategic voting there. I'm talking about something 
that really happened -- and that continues to happen.

What you have mentioned, as to reason 2, asserts a "disastrous" 
impact on BR. That could certainly happen with some voting systems, 
it's not likely with Range, and with reasonably informed voters. 
Basically, poorly-informed voters could indeed make serious mistakes. 
It's natural: if a majority is uninformed, they can fail to vote 
effectively and the loss could be serious, but not, likely, maximal. 
(I have to except the situation where the next World Dictator is on 
the ballot, and everyone loves him. No, I'm talking about that person 
getting elected when a majority are opposed, because they stupidly 
bullet vote for an array of opposing candidates. That is *stupid 
strategy.* The amount of damage depends on the method, but 
practically any method can be abused. Certainly Range can.


>In Range voting, strategic voting refers to something radically 
>different from what was strategic voting in ranked systems: in the 
>latter, it was reversal of preferences. That reversal occurs to me 
>as radically unfair, that is, a system that encourages such 
>reversals is unfair. But Approval and Range don't do that.
>
>
>Neither do most graded Bucklin methods (ie, any of them that don't 
>rely on an inherently ranked method like Condorcet for the tiebreaker).

Right. By the way, I am *not* offended if a voting system can fail in 
some way when faced with a tie, as long as if fails for one of the 
two best candidates, with no major difference in utility. Voting 
systems have various values, and simplicity is one of them, and other 
values might suffer *a little* for simplicity.

I'm proposing runoff Bucklin, and it can get a bit tricky, depending 
on specific runoff rules. I'm suggesting reanalysis of the votes, not 
merely picking the top two Bucklin candidates, but looking at the 
Range winner and any candidate who beats the Range winner pairwise. 
My suspicion is, without having done a thorough analysis, that this 
might encourage more complete ranking (and it's for this, and other 
benefits, that I'd turn the Bucklin ballot into a balanced Range ballot).

>
>I think there are some weird circumstances with multiple majorities 
>in Bucklin that could lead a voter to think they should reverse 
>preference, but ... that is a rare circumstance, difficult to 
>anticipate, and of questionable value.
>
>
>There is no such circumstance for rational voters.

I have none in mind. I just think I've seen some claims.

>  Obviously irrational voters could wrongly conclude this, but that 
> could happen for any method. Range, Approval, and graded Bucklin 
> methods (like GMJ) are all 100% semi-honest if voters have either 
> perfect or zero information about each ballot. (That is, if for 
> instance everyone knows that 20% of voters each are A>B, B>C, and 
> C>D, and nobody knows about the remaining 40%, then all rational 
> strategies are semi-honest)

Basically, in Approval, a full-knowledge voter may need to cast a 
full vote for a tied candidate, when the voter prefers another. But 
in Approval, that's already standard strategy! In Range, that's only 
necessary if the full 100% range vote is needed for the shift. Again, 
it's the same, what you are calling "semi-honest." I would simply say 
that the vote does not fully disclose all preferences.

It is not "dishonest" if I don't tell you something. There is no 
immorality in not mentioning to a buyer of some item from me that I'd 
actually prefer to get more money for it. I approve of an offer, 
100%, if it's what I think I can get.

>However, there are crazy circumstances of incomplete information 
>where non-semi-honest strategies are rational, for all three kinds 
>of methods. For instance, if I know that all other voters will vote 
>purely based on party, and I am the only voter who cares about 
>gender (I want to elect a woman), BUT I have no idea which party is 
>preferred by more voters, I might be rational to approve women who I 
>prefer less over men I prefer more.

No, this is a semantic trick. If you want to vote that way, *you 
prefer the women.* You are making a choice, based on a consideration. 
And we call these considerations "preferences." Given your *complete 
set of preferences*, you prefer the woman over the man.

However, in some *other circumstance*, you might prefer the man. We 
vote based on our choices, and we make our choices, generally, based 
on circumstances. You might prefer the *individual man* over the 
*individual woman*, but you have chose to insure, as best you can, 
the election of a woman, and that's important enough to you that you 
would vote against the individual preference. This *is* a 
"semi-honest" strategy. It simply does not disclose *all* your preferences.

>  That is an unrealistic situation, though, because it very quickly 
> breaks down if I think that there are even a few other gender-noticing voters (
>Asset is an awesome system, but it has one flaw: it is not 
>guaranteed to resolve in any finite time. This is one of the 
>rationales for more-complex, Asset-inspired systems like SODA.

If it is *guaranteed* to resolve in a specific time, it will lose 
some of its power. It's a tradeoff. However, notice: we go to all 
this trouble to elect representatives for legislatures, and then they 
use a process to make actual decisions that are *not guaranteed to 
resolve in any finite time.*

Jameson, you are raising a crazy point. Asset for an Assembly 
election can elect, we can predict, *almost all seats* in very short 
order. Our own Asset election demonstrated the possibilities. It was 
within, I think, the same day, that I transferred assets to Warren to 
give him a Droop quota. I'd have given him more to make it the Hare, 
but we did not have clear rules. What I wanted to do was create a 
majority of the Steering Committee that, then, by unanimity, could 
resolve any other issues.

An Assembly election *does not have to complete* in any particular 
time. The cost of not completing is a vacant seat and some 
unrepresented voters. Assembly rules could still count those seats in 
the basis for majority, so *there is no harm*. The loss is in 
deliberative representation, and that is a natural consequence for 
failure to compromise. If it's direct/representative asset, the 
electors could still actually vote, and they can still ask that any 
member of the Assembly holding a seat introduce motions for them.

Without the Direct/Representative feature, it's a little more 
difficult to compromise, i.e., if the seat elections are totally 
transferring power to the seats, instead of just setting up access 
and defaults. With that, people with quite divergent views could 
still share a seat, i.e, someone who agrees to represent them -- but 
not to vote according to what they say! The whole point of 
deliberative process is to have participants who can change their 
minds, on the spot.

Demoex didn't realize this, and even when it became obvious, they 
thought everyone else was wrong.