News | Skill Based Matchmaking Recap

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Peanits
Peanits Dev, Community Manager Posts: 7,374
edited June 2021 in General News
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Hey folks, it’s Patrick! Your friendly Lead Game Designer on Dead by Daylight, and I’m here to talk about the recent Matchmaking test.

First of all, a big thanks to everyone who played during the 48 hour test! The data we have gathered, along with general feedback has been extremely useful for the team.

"What is SBMM, anyway?"

  • SBMM stands for “Skill Based Match-Making”, and is a number used by the system to attempt to build balanced matches by putting players of equal skill together. You may also hear the term MMR (Match Making Ranking) used to describe the system!
  • Players have a single SBMM Rating shared by all their Survivor characters, but individual Ratings assigned to each Killer they play
  • The SBMM is a dynamic value that adjusts each match based on your performance and the Rating of your opponents (if you do well against someone who has a much higher Rating, your SBMM Rating increases much more than if you had done well against someone with a much lower Rating than you)
  • Note: This is a very general summary of the system. There is a lot more nuance and specialized rules for DbD, so in an effort to keep this brief I am oversimplifying a lot.

One of the main focuses of this test was to try a different approach to how we handle “unrated” players. An unrated player is someone who doesn’t have any matches played that have been tracked by the system. Usually, these players are new. However, they can also be people returning from a break! In this test, we only used matches from the past 3-ish weeks to build our SBMM (rather than our customary months of play data). This meant that our initial SBMM values for most players were a little inaccurate and required some additional games to adjust.

"How did the test go?"

  • Halfway through our test, we were seeing many reports of high-skill Killers being matched against low-skill Survivors. At around 1PM EST on Thursday (around halfway through the test) we enabled a system that would assign unrated Killers a starting Rating based on their other Killers. To put this another way, if you had a high Rating with The Shape and The Trapper then decided to try out The Oni for the very first time, your Oni rating would start higher than the normal default due to your experience with other Killers. Enabling this appears to have resulted in an improvement of match quality, and we intend to improve this system in our next iteration.
  •  Mixed in with this, we also heard many reports of Hillbilly Killers getting matched against new players at a much higher rate than expected. This panned out when we checked our stats: HillBilly kill rates had spiked over the course of the test! It seems as though the matchmaking system is ignoring the proper SBMM value just for Hillbilly and was instead matching HillBilly players using the default “new” player rating no matter what. Thankfully, we were able to track down the problem. Did you notice how I’ve been spelling Hillbilly two different ways during this note? If so, you’ve got a hint about why this bug was occurring. 😉

Overall, our stats showed that as the test continued and people played more, games became more balanced over time. By the end of the test the system was able to match people against similarly skilled opponents the majority of the time.

Going forward, we will continue to refine the system and collect data in the background to improve it further, and will hopefully be moving to this system fulltime Soon™!