# [EM] Proportional preferential voting

David Catchpole s349436 at student.uq.edu.au
Thu Sep 16 22:28:09 PDT 1999

```I was thinking more of explaining what your []or[]'s meant... starting
from the beginning with a sentence explaining the layout of the model and
the structure you describe.

> [The STV 2 winner formula is too complex and yet wrong.
> The transfer denominator is wrong in "the" method as far
>  as I know. Maybe it reviewed every 100 years or so.

Droop or Hare? Droop (1/(n+1)) makes intuitive, operational, normative,
and positive sense.

>
> I don't know much about "norms of voting".
> I retract the words "paradoxes .. can be removed".
> What are "norms of voting". The "_complete_" preferences
>  of voters get separated from the quantities of bundles
>  of papers. It is possible to make the 'loss' point with
>  sample election examples.

I'm using what I've been taught in my university's government department's
parlance- a norm, as in normative economics, is a statement of value or
an axiom... a principle which either is self-evident or is assumed to be
so for the best of worlds. Independence of the removal of irrelevant
alternatives (my particular fave) is a norm of voting because I hold that
elections must be "fair" and that "fair" includes a self-evident "right"
to acknowledge all options without loss whenever one can (which is not
always, because Condorcet paradoxes are an exception). Another example of
a norm of voting is monotonicity- a behaviour of indication will always
have an improving/neutral effect.

>
> This rule doesn't even hold for FPP:
>
> >>  'permuting all preferences before a preference for a
> >>   particular candidate, never makes a difference to
> >>   that candidate's win/lose status'.

Where a Condorcet winner exists, this holds for Condorcet methods.

> I'll name my method IFPP (Improved FPP or enhanced STV)
>
> The two cases:
>
>     A  49
>     ACB 2
>     B  50
>     C  30
>          FPP: A wins, STV: A wins, IFPP: A wins.
>
>     A  49
>     B  50
>     C  30
>     CAB 2
>
>         FPP: B wins, STV: A wins.
>         IFPP: A wins (since (49+50+30+2)/3 = 43.666.. < 49, else B)

I feel I'm starting to understand... I take it IFPP involves- determining
the number of electors and dividing it by 3, and then- holding a runoff
between the one or two candidates who make such a quota. Am I right? A
similar extension which was mooted by a person on this list a few months
ago was progressively going from quota to quota until one had a single
candidate left. For continuous reductions of quota, this evolves into
common or garden Australian STV (STV is a family, not just one electoral
system).

> >> I'd hope to see an example proving that the Condorcet method
> >>  violates the "one man one vote" idea.
> >
> >Huh? (Sorry for abruptness...)
>
> ("man" means "vote", and "vote" means 'effect' or influence).

As in, where n voters of type a are required to change the result, >n of
type b are required to do the same thing? I'll agree with that and maybe
soon I'll come back with an example...

> STV passes that test of "one man, one vote" flawlessly.