[EM] the "meaning" of a vote (or lack thereof)

[Juho Laatu]

On 24.8.2011, at 2.07, fsimmons at pcc.edu wrote:

> But back to a possible generic meaning of a score or cardinal rating:  if you think that candidate X would 
> vote like you on a random issue with probability p percent, then you could give candidate X a score that 
> is p percent of the way between the lowest and highest possible range values.
> 
> Note that this meaning is commensurable across the electorate.

This is the best proposal so far since this takes us as far as offering commensurable ratings. Maybe we should add also voter specific weights to the different issues.

Voters could start from the set of issues that the representative body or single representative covered during the last term. They could adjust those issues a bit to get a list of issues that are likely to emerge during the next term. That makes a list that is the same to all (and that makes the opinions therefore commensurable). Weighting makes the results more meaningful since to some voters some questions might be critical and others might be irrelevant. Without the weights the ratings might not reflect the preference order since we might have misbalance due to too many questions of one kind or due to questions of varying importance.

In principle one could collect the opinions also indirectly by generating an explicit list of issues and asking voters to mark their opinion an weight on each issue. That list could be structured or allow voters to indicate the importance of each group of questions. It is however not obvious how the questions should be grouped. Grouping could also influence the results. It would be also difficult to the voter to estimate the level of overlap between different issues. In practice one may get equally good results by simply asking "how much do you think you will agree with this candidate (from 100% to 0%)".

> A few years ago Jobst gave a rather definitive discussion of this issue.

That is one of the most informative and well written mails of the EM list.

> For example, if you have a choice between alternative X or a coin toss to decide between Y and Z, and 
> you don't care one whit whether or not X is chosen or the the coin toss decides between Y and Z, then 
> (for you)objectively X has a utility value half way between Y and Z.

The lottery approach is not as good as the issue agreement approach. The issue agreement approach can set clear fixed points in the scale, 100% agreement and 0% agreement, which makes it commensurable.

The lottery approach (at least by default) also compares voter utilities, while the issue agreement approach need not (the utility of a 50% agreed candidate need not be half way between the 100% and 0% agreed candidates). Use of utilities makes the lottery approach non-commensurable, if we assume that individual utilities can not be compared as numbers in this way. Percentage of agreements on the other hand is more like a technical fact (has same scale for all voters). And one can add also personal weights to that without making it non-commensurable.

The proportion of agreed (weighted) issues does not give us voter utilities yet. Some voters might care less about the election results than some others. But on the other hand often we don't want to use utilities (= personal strength of preference) in the elections. We rather think that one (wo)man should have on vote. The vote of rich and poor voters should have the same weight. And in the same way the opinion of a voter who says "this is just my opinion" should maybe have the same weight as the opinion of a voter who says "do as I tell you to do". (Anyway, all I'm seeking here is commensurable ratings, not commensurability of personal utilities.)

In the agreed issues approach we thus have votes that are normalized so that the votes of different voters are commensurable. This is different from the more common normalization where the ratings of a ballot are rescaled so that they cover the whole scale from min to max value. The latter normalization depends on what kind of candidates there are, the former one does not.

Do you all agree that ratings can be commensurable? It is of course another question how to get those ratings for some method in a competitive election (and how to derive opinions of the societies from those sincere commensurable ratings).

Note btw also that if we want the outcome to be the utility of each candidate to the society (and elect the one with highest utility), it is not necessary to derive those utilities from the utilities of individual voters. We might as well take a shortcut and derive the society utility from something else, like the issue agreement values.

Juho