[EM] When and how can we speak of "individual utility" and "social utility"?

[Michael Poole]

Abd ul-Rahman Lomax writes:

> How to define individual utility in election methods is not 
> necessarily a problem: the voter defines it. They system provides a 
> means to express such utilities.
>
> Aggregating utilities, however, is obviously not such a simple thing. 
> But we should not let this distract us from the fact that utility 
> analysis is really the *only* approach to judging how well election 
> methods perform, it is not like we have other methods competing with it.
> 
> Election criteria might be considered such methods, but they are 
> clearly indirect. Even the most basic of them, such as the Majority 
> Criterion as usually defined, is clearly flawed in that we can easily 
> propose election scenarios, and not rare ones but common ones, where 
> it requires results that by any reasonable definition of election 
> success are defective. As I've mentioned, if we can't use an election 
> method for a group of people to pick a pizza, how can we expect the 
> same method to work well with picking officers? Picking officers is a 
> *more* difficult problem, not a simpler one.

You may not like those criteria, or the results reached by methods
that satisfy them.  That does not mean the criteria are "clearly
indirect" or the methods "defective".  Kindly stop confusing your
preferences with what is reasonable.

It is ludicrous to claim that a criteria based on ballot markings is
less direct than one based on utility.  No useful definition of
"direct" permits such a claim.

Among other problems, the only utility you can collect before an
election is estimated prior utility, and people are notoriously bad
predictors of the future.  What you really want to measure is
posterior utility (after the term being voted upon).  For reasons like
that, I think social utility is a poor metric by which to judge an
election method, but you will not catch me claiming it is an invalid
metric.

Michael Poole