RogerBW's Blog

I recently ran the vote for the Pearple's Choice Awards, which used to happen on the old Shut Up & Sit Down forum and now happen on discussion.tekeli.li.

I like the Hugo nomination and voting system, so I decided to implement that. Except that apparently they don't make their software public, so I had to write my own. (Well, there's openstv, but it doesn't do the nomination handling, it's an ugly GUI thing rather than command-line, and when I looked for the software's web site I found some completely different vote-counting service which the project has apparently morphed into.)

My model is very simple: rather than have a GUI, each separate program takes a file, processes it, and outputs another file (plus a log of what was done). For example the vote counter checks that all ballots are valid then does the full counting procedure and produces a file of the results.

Counting ballots is easy. Confirming you're working by the rules is harder. I used two sources: the WSFS Constitution, which seems to have a bug at one point (§6.5 nowhere defines what a "run-off candidate" is meant to be), and the Hugo Award notes.

So first you have a bunch of nominations, which have to be reduced to about six. First of all nominations for the same game have to be character-identical; I suppose I could have used BGG IDs, but at least one game wasn't yet listed on BGG, so that's less than ideal. Is a nomination valid in a single category? What about something like Unmatched: do people vote and nominate for the whole system, or for just one game within that system?

Then it comes down to the software. §3.9.1 says that each nomination for a single category is worth one "point", which is divided between all the nominees you list; so obviously rather than commit the sin of using floating point I scaled this up to enough points to be evenly divided between any valid number of nominees (since people were allowed five, that was 60 points). Anyway, each potential nominee gets both a number of points and a number of votes from which it got those points, and the lowest-point options are eliminated – and their points distributed among other nominees. (There's a lot of that in this system, redoing a thing from scratch after some options are eliminated rather than looking at what's left.)

Nominations done! Time to count the votes. These are a bit simpler: take every vote's first choice. If there's an absolute majority, that's the winner. Otherwise eliminate the nominee that got least votes, strike out the votes at the top of the ballots voting for it, and go back to taking every vote's first choice, until there's a majority. But you don't list runners-up in order of elimination, oh no: instead you strike out all votes for the winner, then run the whole multi-round process again. I'm sure someone had a reason for this.

And explain to people the difference between listing everything including No Award and simply listing the things you care about.

This is the first time I've written software with explicit comments linking to the points of the voting system which a chunk of code implements.

If anyone else wants to run a vote like this, give me a shout. I'll probably put the code and documentation on GitHub eventually, but I say that a lot and don't seem actually do to it very much. Maybe I'll rewrite it in Rust first.