IRV sometimes is not monotone, and sometimes is very terrible

Kirshenbaum is infact IRV.

In image above:

IRV will eliminate A, and B will be the winner.

Here IRV is not consistent with Condorcet winner (without ambiguity   “A”).

Two more people who loved C ,  start to love B and bring B to their best choice.  This will Cause B not to be the collective Choice anymore !!

NOW IRV removes C and A is the winner !

Here IRV is good but is was not monotone from 35 to 37 loving B

 

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