[EM] Proportional preferential voting

[David Catchpole]

On Mon, 20 Sep 1999, David Catchpole wrote:

> for probabilistic models of choice-
> 
> "The removal or addition of an option which has not been selected will not
> reduce the chances of any outcome where that option is not chosen"

Oops! Gave improper definition of probabilistic IIA (got into the groove
of writing "removal or addition") This should read...

for probabilistic models of choice-

"The removal (addition) of an option which has not been selected will
not reduce (increase) the chances of any outcome where that option is not
chosen"