Is approval voting an ‘unmitigated evil’?: A response to Brams, Fishburn, and Merrill

Brams, Fishburn, and Merrill (1988) contend that the indeterminacy of approval voting (AV), introduced in our paper (1988), is not a vice, but a surpassing virtue of AV. They do not compare the negative versus the positive features of AV, so their assertion remains a conjecture. Our response emphasizes the need to determine the costs of AV and to evaluate them against any merits. Moreover, by correcting and answering BFM's comments, the argument against AV becomes much stronger. This is because we show that AV's region of indeterminacy is quite large; it includes most profiles. Some of the consequences of this instability are that the AV outcome can negate the voter's true wishes, that the AV outcome can be volatile even to minor fluctuations of voter's decisions, and that AV is one of the most susceptible systems to manipulation by small groups of voters (for example, small, maverick groups could determine the AV outcome). Under specific circumstances, AV may be appropriate. To identify these situations we propose the more accurate name of the "Unsophisticated Voter System."