Alternative Rankings

Bias is a bit of an ugly word, isn’t it? It certainly has become one of those battle phrases in the culture war, where both sides of the argument accuse the other of forcing their biases onto society. Board game reviews frequently need to justify themselves for their biases affecting their views. Dan Thurot 🗄️ recently wrote a very eloquent piece on the matter, diving deeper into different kinds of biases.

But bias also has a well defined meaning in statistics. Moving from emotions to cold hard numbers, the word bias loses its antagonistic nature and simply becomes a measurement one might want to minimise or remove entirely. Hence, debiasing the BoardGameGeek (BGG) ranking is about asking the question what it would look like if we removed the influence of a particular parameter. One such parameter is a game’s age: we’ve seen in the previous article that ratings have gone up over time, so removing the age bias from the BGG ranking means correcting for this trend.

BoardGameGeek (BGG) users can select their country of residence in their profile. The main purpose is to find other users in your region to play face to face or maybe trade games, but but over here at Recommend.Games we obviously cannot help ourselves but to use this information for some interesting statistics. 🤓

Let’s start with the usual disclaimer: We will have to rely on whatever information BGG provides. In particular, users can freely choose their country. As mentioned, this is meant to be the country of residence, but some users might rather choose their country of origin – or some outright nonsense. There are 19 BGG users who claim to be from 🇦🇶 Antarctica, for example. While I’m sure that the long polar nights on lonely research stations are perfect for playing board games, I’m not sure if they have a lot of time to rate them on BGG. 🐧 (If they actually did, Antarctica would have 6,880 ratings per 100 thousand residents, which would make them the second biggest board game enthusiasts in the world – only behind the 🇻🇦 Vatican’s 6 reported users, resulting in almost 20,000 ratings per 100 thousand residents. 🙏)

We have some pretty exciting news! 🤩 Since 2022-02-22, we’ve been using a new and improved ranking as the default sorting for our front page at Recommend.Games.

… What do you mean, you haven’t noticed there’s a R.G ranking? You know, that thing that’s referenced in the statistics? … You haven’t ever opened that view?!? 😱

OK, let’s back up for a second. R.G’s primary purpose is a recommendation engine, that is, finding personalised game recommendations based on a user’s preferences (in this case as expressed through their BoardGameGeek ratings). But we want to show some games to the users immediately when they load the start page, before entering their user name. Think of these games as recommendations for… anyone. What games would you recommend to a person if you didn’t know anything about their taste? This is the implicit purpose of any “Top X entities” list. Since this is a recommendation site, we’d like to make this claim explicit, so the R.G ranking has always been those “recommendations for everyone”. What’s changed is the way those recommendations are calculated.

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.