In your earlier post (Election-methods digest, Vol 1 #576, Message 7) you defined INI ("Independence of Non-supporting Information") asDate: Fri, 02 Apr 2004 21:39:43 -0800 From: Richard Moore <[EMAIL PROTECTED]> ...
But what did you think of INI?
-- Richard
"If X wins and Y loses, and margin(X,Z) <= margin(Y,Z), then removing candidate Z from the election shall not cause Y to win and X to lose."
This sounds like a reasonable criterion, but as stated above I don't think it has relevance to Arrow's IIA criterion because IIA relates to how the election result might change when you remove a candidate from the vote count, not from the election. (In the former case, the votes don't change; in the latter case voters may strategically change their voting preferences based on which alternative candidates are running.) A more concise statement of INI (if this is what you meant) might be:
"If X wins and Y loses, and margin(X,Z) <= margin(Y,Z), then removing candidate Z from the COUNT shall not cause Y to win and X to lose."
In the case of CR and Approval all of Arrow's criteria, including the following interpretation of IIA, hold:
"If X wins and Y loses then removing candidate Z from the count shall not cause Y to win and X to lose."
- Ken
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