When I was first investigating voting methods, I wanted to understand the various criteria by which they’re evaluated. Some are fairly straightforward

The majority criterion states that if there is a single candidate preferred by a majority of voters to all other candidates, then that candidate should win.

whereas others would be difficult to explain to anyone without a background in math.

Independence of Smith-dominated alternatives (ISDA) is a voting system criterion defined such that its satisfaction by a voting system occurs when the selection of the winner is independent of candidates who are not within the Smith set, the smallest non-empty set of candidates in a particular election such that each member beats every other candidate outside the set in a pairwise election.

Thinking about these helped move me away from “voting method X is awesome” towards “what criteria does this system satisfy?” There’s a whole list of them and it’s arguable as to which ones are relevant. To make the situation hairier, Arrow’s impossibility theorem says that no ranked preferences voting system can ever satisfy all criteria.

The next logical question to ask is which criterion is the most important. I ran across an old site where some guy talked about the evaluation of ranked-ballot voting methods. He ranks the criteria in order of importance to him in an attempt to determines which system best fits his concerns. Considering that everyone has different concerns, I’ve started to build a toy that will help that exploration.

You drag the tabs on the left in order of preference and the toy will tell you which voting systems satisfy your top criteria. The back-end logic was easy enough to build; Finding ways to concisely explain each criterion is turning out to be surprisingly difficult.