Last time we examined the Glicko-2 model and understood how it worked mathematically. This time we shall focus on implementing the Glicko-2 system for tennis.

Let’s establish a few of the ground rules, 1) we will be using the constants mentioned last week (the base rating as 1500 and the initial deviation as 400 / ln (10. Other constants remain. 2) Despite Glicko-2’s ability to do batch updates (i.e. for a tournament), after trying both methods I found that there is no significant benefit in batch updates and, in fact, updating each match individually proves to have better accuracy. 3) We need to have two ratings per player, one on serve and one on return. (more…)