All one-round voting systems that allows ballot truncation are vulnerable to bullet voting, resulting the same results of plurality voting. For instance, suppose that some voter has A as his/her first preference. S/he can vote like this:
<br><br>Approval: A: approved; B: rejected; C: rejected; D: rejected ...<br>Range (0 - 100 scale): A: 100; B: 0; C: 0; D: 0 ...<br>Preferential (IRV, Condorcet, etc): A>B=C=D=...<br><br>Additionally, there are several instances which only binary input voting systems are reasonable. Complex systems are hard to adopt in low-educated underdeveloped countries.
<br><br>This system, called Improved Approval Runoff (IAR), has the goal to resist bullet voting through simple ballots.<br><br>Description:<br><br>1) On the first round, the voter can vote for as many or as few candidates as desired.
<br>2) If some candidate has more than 50% of approvals, the most approved is elected.<br>3) If not, that candidate runs a second round against other candidate - the most approved after a new count which the votes for the first one are reweighted to 1/2.
<br>4) The winner is the candidate who receives a majority of votes on the second round.<br><br>On computer simulations, the top-two approval runoff method selected more times the Condorcet winner than any Condorcet method. I think that IAR is slightly fairer than top-two approval runoff under real voters.
<br><br>Any comments?<br> <br>________________________________<br>Diego Santos<br>