Majority Acceptable Score voting: Difference between revisions

Majority Acceptable Score voting works as described below. Technically speaking, it's the [[graded Bucklin]] method which uses [[Three-level ballots|3 grade levels]] and breaks median ties using [[Score voting]].

# Voters can givesupport, accept, or reject each candidate. 0,Blanks 1,count oras 2/3 points.of a rejection and 1/3 of an acceptance (so 75% blanks counts as 50% rejections).

# a. If there are any candidates givennot ''above'' 0rejected by a majority, then eliminate all who aren't (that is, those with half or more ''at'' 0)are.

#* b. (RepeatIf stepthere 2a,are usingany "atcandidates orsupported belowby a majority, 1"then insteadeliminate ofall "atwho 0"aren't.)

Step 2b probably doesn't matter, because any majority-2supported candidate that exists would almost certainly win in step 34 anyway. But step 2b is part of Bucklin voting, which was used in over a dozen US cities during the Progressive era. Also, it lets you say the whole method in one sentence, ifusing the personidea you're talking to understandsof medians: "choose the highest score among the candidates with the highest median".

If all the candidates in the first round got a majority of 0's, then you can still find two finalists as explained above. But the voters have sent a messageessage that none of the candidates are good, so one way to deal with the situation would be to have a rule to allow candidates to transfer their 2-votes to new candidates who were not running in the first round, and if those transfers would have made the new candidates finalists, then add them to the second round along with the two finalists who did best in the first round. In that case, since there would be more than 2 candidates in the second round, it would be important to use MAS for the second round too.

Assume voters in each city give their own city 2; any city within 100 miles, 1; any city thatbetween is100 overand 200 miles, awaya or is the farthest city, 0blank; and theany restcity (thosethat betweenis 100 andover 200 miles), get 1away or blankis withthe 50/50farthest chancecity, 0. (These assumptions can be varied substantially without changing the result, but they seem reasonable to start with.)

!explicit 1's

!explicit 0's

!total 0's+2/3 b's

|bgcolor="#fff"|370

|bgcolor="#cfcfff"|27.474

|bgcolor="#bfbcfc"|9849.67

|bgcolor="#fff"|3017

|bgcolor="#cfcfff"|49.926

|bgcolor="#ffffcc"|6559.17

|bgcolor="#fff"|2815

|bgcolor="#fff"|1326

|bgcolor="#fcc"|5259.87

|bgcolor="#fff"|(6477.27)

Memphis is explicitly given 0 by a majority, and is eliminated. Chattanooga and Knoxville are both given 0 by a majority implicitly, so they are eliminated. Of the remaining two, Nashville has a higher scoreremains and wins.

If Memphis voters tried to strategize by rating Nashville and Chattanooga at 0 in the above scenario, it would take a bit over half of them to successfully execute the strategy. Even if all the Memphis voters strategized, Chattanooga and Knoxville voters could protect Nashville against this strategy asif long as under half2/3 of thosethem who had givengave Nashville a blank above switched to giving it a 1 (or a 2). Note that the offensive strategy involves moving a natural 1 down to the extreme value of 0, but the defensive strategy only means changing a lazy blank to a natural 1 (not to the extreme value of 2).

[[Category:Graded Bucklin systemsmethods]]