[EM] Why I prefer ranked-choice voting to approval voting
jameson.quinn at gmail.com
Tue Oct 11 10:01:54 PDT 2016
First off: thank you, Jeff, for a thought-provoking piece. I'm going to
disagree with you on some points, but it's clear that you're arguing in
Second: I'm sorry, but I really can't bear the name "RCV" in a voting
methods discussion. I know that's what IRV is frequently called in actual
laws, but to me "ranked choice voting" is obviously the correct term for
the whole class of voting methods which includes Condorcet, Borda, and IRV;
not just for IRV alone.
So, on to the body of your argument: that (according to you) the cognitive
burden of IRV is lower than approval, Condorcet, or plurality.
I agree with you on one point: thinking in terms of cognitive burden is an
important, and productive, way to consider voting systems. I also
acknowledge that approval's apparent simplicity is less of an advantage
than one might think, once you consider the cognitive burden.
However, I strongly disagree with you that IRV has a low cognitive burden
in practice, for two reasons.
The first, and most important, is that IRV does not actually remove the
need for strategic thinking. Yes, it obeys LNH, so once you've decided to
rank your favorite in first place, you have no reason not to include your
second choice on the ballot too. But there's an important, and predictable,
class of election scenarios where it's strategically crucial NOT to rank
your favorite first: center squeeze scenarios. If you have two candidates
at ideological opposite points, with a third candidate in the middle near
the median voter, it is actually quite common for the center to have the
lowest first-choice support and get prematurely eliminated. This kind of
thing happened in Burlington 2009; in multiple recent French elections;
tragically, in Egypt 2011; and would have happened in the US 2000 if Nader
had gotten over 25%. In this case, the correct strategy for one group of
voters is to rank their true first choice in second place. Understanding
this, and correctly seeing when it applies, is a HUGE cognitive burden for
Second, IRV requires strict ranking. That's a nontrivial cognitive burden
when there are more than a handful of candidates. If there were 15
candidates in a race, how should a voter decide exactly which of them to
give 8th preference? It's much easier to use absolute grades, as in
Majority Judgment. (Behavioural research bears this out; strict ranking is
harder than rating, for anything more than 3 or 4 options.)
On the other hand: is the strategic burden for approval voters actually
that high? I think not. Consider the rule used by Ka-Ping Yee in his voting
system visualizations <http://zesty.ca/voting/sim/>: a randomly-assigned
strict threshold. This requires no strategic doublethink, yet leads to
near-ideal outcomes under his assumptions. My point is that under approval
sophisticated strategy is not nearly as important as under IRV.
But still, I think you have a point. Approval does have a cognitive burden,
and we should account for that. That's precisely why I've been working on
MAS (majority acceptable score) as an option: it's a simple 3-level voting
system with an absolute minimum of cognitive burden. I believe that under
MAS, in basically all everyday voting scenarios, a naive sincere ballot
will be strategically optimal, or close enough to it that most voters
ps. You mention Condorcet, and argue that the strategic cognitive burden is
higher than IRV. I disagree; but since Condorcet comes with a higher
cognitive burden in just figuring out why a given candidate won, I agree
that Condorcet methods are probably not best for large-scale elections.
2016-10-11 8:54 GMT-04:00 Jeff O'Neill <jeff.oneill at opavote.com>:
> I recently wrote a blog post explaining why I prefer ranked-choice voting
> (i.e., IRV or alternative vote) to approval voting. It is a quite
> different kind of argument than most of the posts here because it is a
> policy argument rather than a mathematical one. Nevertheless, I thought
> people here might find it interesting. I'd love to hear your comments and
> any counterarguments as well.
> I've copied the post below and you can also find it here:
> Why I prefer ranked-choice voting to approval voting
> Voting is not an easy task for a voter. I don't mean taking time off
> work, getting to the polls, and waiting in line, etc. I mean, when you are
> standing there in the ballot box, you have to decide what vote you want to
> cast given the options presented to you. For example, a Jill Stein
> supporter may be torn between supporting her favorite candidate and voting
> for a candidate who has a better chance of winning the election. I'll
> refer to this as the *cognitive burden* of expressing your vote.
> In this post, I'll address the cognitive burden of three different types
> of voting:
> 1. Plurality voting (i.e., selecting one candidate)
> 2. Approval Voting
> 3. Ranked-choice voting
> OpaVote <http://www.opavote.com/> supports all three of these voting
> methods if you want to try them out yourself.
> Plurality Voting
> Plurality voting is very simple, a voter simply picks one candidate.
> There is, however, a cognitive burden when there are more than two
> candidates. A voter presumably wants her vote to matter. Accordingly, a
> voter should not necessarily select her favorite candidate, but instead
> select her favorite candidate who has a reasonable chance of being elected.
> Consider the current U.S. Presidential election. I'm a big supporter of
> the Green Party, but Jill Stein is not going to win the election. I'd like
> to vote for the Green Party, but instead I'll vote for Hillary because that
> is the best way for my vote to make a difference. Others will vote for the
> Green Party out of principle.
> Where there are more viable candidates, the cognitive burden is much
> higher. The French 2012 elections for President had ten candidates in
> the first round. A voter thus needed to consider which candidates had a
> chance of winning, and then select her favorite among those who had a
> chance of winning.
> Approval Voting
> With approval voting, a voter has the option to approve as many candidates
> as they like. The candidate with the most approvals is the winner. For
> someone whose first choice is Jill, the voter may, for example, approve of
> Jill and Hillary and not approve Donald and Gary.
> Approval voting, like plurality voting, is very simple in practice. A
> voter just selects one or more candidates. But Approval voting suffers
> from similar cognitive burdens as plurality voting. How do you draw the
> line between candidates you approve and candidates you don't approve?
> Consider a voter whose true preferences are:
> 1. Jill Stein
> 2. Hillary Clinton
> 3. Gary Johnson
> 4. Donald Trump
> Clearly, this voter will approve Jill and will not approve Donald, but
> what should she do with the other two candidates? Should she also approve
> Hillary? Giving Hillary an approval may help Hillary beat Jill, but she
> would certainly prefer Hillary to Gary or Donald. Similarly, this voter
> may not like Gary, but she may dislike Donald so much that it is worthwhile
> to approve Gary to minimize the chance that Donald is elected.
> Phew... that is a lot of thinking to do. It would be even harder if Jill
> and Gary had better chances of being elected.
> In sum, approving any candidates other than your favorite can hurt your
> favorite. Not approving candidates can help your least favorite get
> elected. Approval voting thus creates a significant cognitive burden for
> Ranked-Choice Voting
> With ranked-choice voting, a voter ranks the candidates in order of
> preference, similar to the picture above. In my view, this has the least
> cognitive burden among the three methods discussed here. It is easy for a
> voter to pick her favorite candidate, pick her second favorite, and so on.
> This kind of ballot has low cognitive burden because a voter doesn't have
> to consider which candidates are viable.
> But, you may ask, "Doesn't a voter have to think about whether their
> second and later preferences might hurt their first preference? For
> example, should a Jill Stein supporter not rank Hillary second because it
> might help Hillary beat Jill?"
> The great think about ranked-choice voting is that the answer to this
> question is a clear and resoundingNO!!! Your second and later choices
> cannot harm your first choice! Your second preference is only ever
> considered at all if your first preference has definitively lost. Voting
> geeks cause this the later-no-harm criterion
> Voters thus need to be educated that later choices do not hurt earlier
> choices so that voters are encouraged to rank as many candidates as
> possible. The more candidates a voter ranks, the greater influence the
> voter has in the outcome of the election.
> Accordingly, ranked-choice voting has the lowest cognitive burden. A
> voter simply needs to select their first choice, second choice, and so
> forth. The voter does not need to consider which candidates are viable.
> (For voting geeks who are leaping out of their seats to make points about
> other voting systems criteria
> <https://en.wikipedia.org/wiki/Category:Voting_system_criteria>, please
> keep reading.)
> Other Stuff...
> In my view, it is extremely important to make it as easy as possible for
> voters to vote, and, for the reasons described above, ranked-choice voting
> does this better than both plurality and approval voting.
> I want to briefly address another form of ranked voting called Condorcet
> voting. Condorcet voting also uses a ranked ballot, but the votes are
> counted in a different way. Condorcet voting doesn't satisfy the
> later-no-harm criterion mentioned above, so it is possible that your
> second and later choices could hurt your first choices. The possibility,
> however, that your second and later choices hurt your first choice is so
> small that, for practical purposes, a voter to cannot take this into
> account, and thus Condorcet voting has the same cognitive burden as
> ranked-choice voting. While Condorcet voting is a great voting method, I
> still prefer ranked-choice voting for public elections, and I'll address
> that in a future blog post.
> Another point to mention is that detractors of ranked-choice voting
> complain that ranked-choice voting does not satisfy other voting systems
> criteria, such as the monotonicity criterion
> <https://en.wikipedia.org/wiki/Monotonicity_criterion>. While this is
> certainly true, for practical purposes, a voter cannot take the
> monotonicity criterion into account when casting a vote. It is just far
> too complicated and you would need to know how everyone else is going to
> vote. The non-monotonicity of ranked-choice voting thus doesn't create a
> cognitive burden.
> Please let me know what you think, especially if you disagree. I am happy
> to post any well-reasoned dissent as comments or even give you the
> opportunity to write your own blog post in rebuttal.
> Election-Methods mailing list - see http://electorama.com/em for list info
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the Election-Methods