This is based on social utility efficiency calculations.
See: http://RangeVoting.org/BayRegDum.html and http://RangeVoting.org/vsr.html
You can't use real world polls to calculate this, because you can't read people's minds, and you can't run hundreds of millions of elections and poll every single voter anyway. Instead what social utility calculations do is take scenarios of the utilities candidates have for a range of choices, and then determine how voters would vote based on those levels of preference for the options. We then look at the average utility produced by the selection of the winner, scaled as a ratio of "distance" covered from the utility produced by a random winner, to the utility produced by the ideal winner. You do millions of simulations, using hundreds of different models of voter behavior, from strategic, to honest (honest is trivial, strategy is more complicated), and from totally ignorant to totally informed, with 2 candidates, with 3, with 4, with 5, etc. You then see the average satisfaction produced by the various voting systems. Range Voting dominates the other methods, in every combination of 5 fundamental parameters we tried.
You can run our software for yourself, and try to find bugs if you like.
http://RangeVoting.org/IEVS/
Also, we often get asked "Why are you using a computer simulation instead of real humans?" So, http://rangevoting.org/WhyNoHumans.html
Re: Erroneously?
See: http://RangeVoting.org/BayRegDum.html
and http://RangeVoting.org/vsr.html
You can't use real world polls to calculate this, because you can't read people's minds, and you can't run hundreds of millions of elections and poll every single voter anyway. Instead what social utility calculations do is take scenarios of the utilities candidates have for a range of choices, and then determine how voters would vote based on those levels of preference for the options. We then look at the average utility produced by the selection of the winner, scaled as a ratio of "distance" covered from the utility produced by a random winner, to the utility produced by the ideal winner. You do millions of simulations, using hundreds of different models of voter behavior, from strategic, to honest (honest is trivial, strategy is more complicated), and from totally ignorant to totally informed, with 2 candidates, with 3, with 4, with 5, etc. You then see the average satisfaction produced by the various voting systems. Range Voting dominates the other methods, in every combination of 5 fundamental parameters we tried.
You can run our software for yourself, and try to find bugs if you like.
http://RangeVoting.org/IEVS/
Also, we often get asked "Why are you using a computer simulation instead of real humans?" So, http://rangevoting.org/WhyNoHumans.html
CLAY