[EM] Inclusion Voting

[James Green-Armytage]

Perhaps this would be a very good debate-inclusion voting method (where
the number of participants is predetermined)...

<beginning of definition>

0. The number of participants in the debate will be T.
1. Ranked vote.
2. Beatpath/ranked pairs tally, producing an ordering of the candidates.
Identify the top C candidates in the ordering. These can be called the
members of the "C set".
3. Modified CPO-STV (comparison of pairs of outcomes by single
transferable vote) tally, to fill all T slots in the debate. The tally is
modified such that it only considers outcomes which contain all members of
the C set.

<end of definition>

	You can calibrate T and C as you like, to get the desired size of the
debate and the balance between breadth and centrist depth / inclusion of
likely winners. For example, T=10, C=4. That's a ten person debate which
necessarily includes the top four candidates in the beatpath/ranked pairs
ordering. If you want a smaller debate you could do T=5, C=2. Or T=2, C=2,
in which case the beatpath/ranked pairs ordering is all that matters. Or
you could do T=15, C=0, in which case there is no C set and the ordinary
CPO-STV tally is all that matters.
	For presidential elections, it might make sense to start with larger
debates and then follow with progressively smaller debates. However,
exclusion from the smaller debates should not mean that a candidate is out
of the running. 

James Green-Armytage