A voting system is consistent if, when the electorate is divided arbitrarily into two (or more) parts and separate elections in each part result in the same choice being selected, an election of the entire electorate also selects that alternative. Smith calls this property separability and Woodall calls it convexity.
It has been proven a ranked voting system is consistent if and only if it is a positional voting system. Borda count is an example of this.
The failure of the consistency criterion can be seen as an example of Simpson's paradox.
Famous quotes containing the words consistency and/or criterion:
“The lawyer’s truth is not Truth, but consistency or a consistent expediency.”
—Henry David Thoreau (1817–1862)
“Faith in reason as a prime motor is no longer the criterion of the sound mind, any more than faith in the Bible is the criterion of righteous intention.”
—George Bernard Shaw (1856–1950)