Top 100

This is the second part of a series explaining and analysing the BoardGameGeek rankings. Read the first part here.

Last time I left you with the nice result that BoardGameGeek (BGG) calculates its ranking by taking users’ ratings for a particular game and then add around 1500-1600 dummy ratings of 5.5. This so-called geek score is used to sort the games from best (Gloomhaven) to worst (Tic-Tac-Toe).

One detail however we touched on in passing, but did not resolve, is how that number of dummy ratings develop over time. When the current calculation method was introduced, BGG founder Scott Alden mentioned that this number would be pegged to the number of total ratings, but did not reveal any details. Challenge accepted!

TL;DR: BoardGameGeek calculates its ranking by adding around 1500-1600 dummy ratings of 5.5 to the regular users’ ratings. They called it their geek score, statisticians call it a Bayesian average. We use this knowledge to calculate some alternative rankings.

I often describe BoardGameGeek (BGG) as “the Internet Movie Database (IMDb) for games”. Much like its cinematic counterpart, the biggest board game database not only collects all sorts of information obsessively, but also allows users to rate games on a scale from 1 (awful - defies game description) to 10 (outstanding - will always enjoy playing). These ratings are then used to rank games, with Gloomhaven occupying the top spot since December 2017.