[EM] DH3 pathology, margins, and winning votes

[Warren Smith]

I attempted to write a careful discussion of these matters
for the general public in the CRV's usual inimitable style.

Anyhow, the interesting thing is that contrary to various
previous not-careful claims, it appears that the "DH3 pathology"
clobbers ALL condorcet methods, whether equalities are permitted
in votes or not, and whether margins or winning votes are used -
doesn't matter.

In my opinion this is a very severe problem for all Condorcet voting methods
(as well as Borda) and a good reason to prefer IRV, plurality, approval,
or range voting, all of which are immune to the DH3 pathology.   

(note: a previous post on RV by me about DH3 contained errors which this
web page repairs.)

Warren D Smith
http://RangeVoting.org