I've been reflecting on my
proposal for making the Hugos less gameable. I think the principle is correct, that the number of nominees should automatically increase in categories where an algorithm detects slate-like behaviour. I now favour reducing the number of nominations per nominator to four, and having between five and ten nominees per category. That would prevent any two slates from taking over a category, assuming the algorithm increased the number of nominees to ten for that category (unless they were very well-organised in getting a large number of nominators nominating different subsets of the slate, which would at least remove all deniability about what they were doing).
But I don't think my algorithm for detecting slates is optimal. The problem is that the numbers that stand out as a slate in categories like Best Novella and Best Short Story would look perfectly normal in Best Dramatic Presentation: Long Form or Best Professional Artist, because there are many fewer eligible candidates, and so the most popular ones inevitably get more nominations.
So I'm after a piece of data that's not in the posted summaries. How many items in total were nominated in each category in previous years, especially 2013 and 2014, going all the way down to items that received only a single nomination (although it would also be good to know the number that got five or more nominations)? Does anyone have access to that data, and are they able to share it?