[EM] SODA clarification

[Jameson Quinn]

2011/7/6 Andy Jennings <elections at jenningsstory.com>

> Jameson,
>
> I have become confused about one point of operation in SODA.  Take this
> scenario:
>
> 35 A>B>C
> 34 B>C>A
> 31 C>A>B
>
> If A delegates to A,B then does B have 69 votes he can delegate to B,C or
> does he have only 34 he can play with?
>
> In other words, can votes delegated from one candidate to another be
> re-delegated to a third candidate?
>

B has 34. Delegable votes are only bullet votes. In fact, a real SODA
scenario would probably be more like:

25 A (>B)
5 A,X
5 A,B
26 B (>C)
4 B,X
4 B, C
29 C (>A)
1 C,X
1 C,A
Initial totals: 36A, 39B, 35C
Delegable: 25A, 26B, 29C

Note that in this example, C has the most delegable votes and would decide
delegation first, even though B has the most total initial votes. In this
case - a Condorcet cycle - the result would be the same no matter who
delegates first, as long as all candidates use correct strategy. But there
are cases where it wouldn't be:

25: Left (>X)
15: Left, Center
5: Left, Right
25: Center (>Right)
30: Right (>Center)

The candidate Left has not declared any delegable preferences, but the left
voters clearly tend to prefer Center over Right. Center is the Condorcet
winner, but Right would get the chance to delegate before Center, and thus
would be the strategic winner under SODA. If delegation order went in order
of total votes instead of delegable votes, Center would win.

Hmm... now that I look at this scenario in black and white, I'm starting to
think that delegation order should be in order of total, not delegable,
votes. Not that there isn't a case to be made for Right in this election; if
Center were really a better result, then they should get either Left's
delegation or more delegable votes from the nominally voters who chose
[Left, Center] here. This argument like FairVote's handwaving arguments
about "strength" of support - which is not necessarily invalid just because
it's imprecise and easy to reduce ad absurdem. But... I think that having
this scenario go to Right puts too much of a burden of strategic calculation
on the [Left, Center] voters.

So, yet another adjustment to SODA, I think. Delegation choice goes in
descending order of total votes; the person with the most total votes gets
the "first move". If my grounded intuition is correct, this should not
matter when there's a 3-way cycle, only when there's a pairwise champion
(CW).

Hopefully this will be the last time I have to adjust SODA. Also note that
all the adjustments so far have been minor tweaks; any of the versions so
far would work well, though I believe they have been steadily improving.
Current rules, as always, are at
http://wiki.electorama.com/wiki/Simple_Optionally-Delegated_Approval

JQ


> I looked at the wiki and still am unclear on this.  I still have the
> original SODA proposal in my head (where votes could not be delegated
> multiple times) and I can't remember if we've changed this detail at some
> point.
>
> Thanks,
>
> Andy
>
>
>
> On Tue, Jul 5, 2011 at 12:39 PM, Jameson Quinn <jameson.quinn at gmail.com>wrote:
>
>> Russ, you said that SODA was too complicated. In my prior message, I
>> responded by saying that it was actually pretty simple. But thanks for your
>> feedback; I realize that the SODA page was not conveying that simplicity
>> well. I've changed the procedure there from 8 individual steps to 4 steps -
>> simple one-sentence overviews - with the details in sub-steps. Of these 4
>> steps, only step 1 is not in your proposal. And the whole of step 4 is just
>> three words.
>>
>> The procedure is exactly the same, but I hope that this version<http://wiki.electorama.com/wiki/Simple_Optionally-Delegated_Approval#Procedure>does a better job of communicating the purpose and underlying simplicity of
>> the system.
>>
>> Thanks,
>> Jameson
>>
>> ----
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>> info
>>
>>
>
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