Activision said Warzone matchmaking would be explained later. Where is that explanation, and where is the Experimentation Methods paper?
TL;DR: Activision said Warzone matchmaking would be discussed later, but that explanation still doesn’t appear to exist. They also listed an “Experimentation Methods” matchmaking paper for Fall 2024, which also seems unreleased. At the same time, detailed match/SBMM data that players reportedly received via SAR exports in early 2025 appears to be missing from recent exports. What changed?
Back in January 2024, Activision published a matchmaking blog, but made clear it was focused on Multiplayer only:
> “This blog focuses on how matchmaking works across Multiplayer only.”
They then said matchmaking in other modes, including Warzone, would be discussed later:
> “We will be continuing the conversation about matchmaking in other modes (such as Call of Duty®: Warzone™ and Ranked Play) at a later date.”
Source: Activision, Call of Duty Update: An Inside Look at Matchmaking
https://www.callofduty.com/blog/2024/01/call-of-duty-update-an-Inside-look-at-matchmaking
Ranked Play eventually got its own whitepaper in December 2024, but as far as I can tell, Warzone has still not received an equivalent explanation.
In April 2024, Activision also published the first matchmaking whitepaper and listed the planned schedule for the series. That schedule included an Experimentation Methods paper for Fall 2024:
> “Experimentation Methods - Fall 2024”
Source: Activision Research, Call of Duty Matchmaking Intel
https://research.activision.com/publications/2024/04/callofduty-matchmaking-intel-ping
That same planned paper was still listed months later:
> “Experimentation Methods - Fall 2024”
Source: Activision Research, Call of Duty Matchmaking Intel – White Paper #2
https://research.activision.com/publications/2024/07/Call-of-Duty-Matchmaking-Intel-02
As far as I can tell, that paper was never released either.
Activision did publish a Ranked Play paper in December 2024, but that was about 4v4 multiplayer Ranked Play, not Warzone:
> “Ranked Play is Call of Duty's competitive ranked Multiplayer mode, following the rules used by the Call of Duty League in 4v4 gameplay.”
Source: Activision Research, Call of Duty Matchmaking Intel – White Paper #3
https://research.activision.com/publications/2024/12/Call-of-Duty-Matchmaking-Intel-03
So my question is simple:
Where is the Warzone matchmaking explanation, and where is the Experimentation Methods whitepaper?
Warzone matchmaking is not the same as 6v6 multiplayer. Resurgence and Battle Royale involve:
- much larger lobbies
- squad-fill logic
- party size differences
- server/datacentre selection
- region population differences
- bots/casual playlists
- ranked vs normal vs LTM rules
- server capacity constraints
- longer match lifecycles
- placement-based outcomes
- post-death spectating/redeployment mechanics
The Ping paper is useful, but it still leaves major Warzone questions unanswered.
For example, Activision says the client runs QoS checks against datacentres:
> “During a game's start-up, your game client runs a process to determine the closest data centers and get a good measurement of your ping and packet loss to each.”
Source: Activision Research, Matchmaking Series: Ping, p. 6
https://research.activision.com/content/dam/atvi/activision/atvi-touchui/research/publications/docs/Call-of-Duty-Matchmaking-Series-PING.pdf
They also say matchmaking does not only consider your best datacentre:
> “For example, data center 2 might be the closest data center with the lowest ping, but data centers 3 and 4 can be equally as good with negligible impact to player experience.”
Source: Activision Research, Matchmaking Series: Ping, p. 7
https://research.activision.com/content/dam/atvi/activision/atvi-touchui/research/publications/docs/Call-of-Duty-Matchmaking-Series-PING.pdf
And they say search constraints can relax over time:
> “As the time searching for a match increases, we may expand our search to include data centers with higher pings.”
Source: Activision Research, Matchmaking Series: Ping, p. 10
https://research.activision.com/content/dam/atvi/activision/atvi-touchui/research/publications/docs/Call-of-Duty-Matchmaking-Series-PING.pdf
That matters in Warzone, where being placed into the wrong server or region can completely change how a match feels.
Transparency seems to have gone backwards
In early 2025, players discovered that Activision subject access request exports contained extremely detailed match-level data, including hidden skill-related values.
PC Gamer reported that Activision would send players detailed per-match data, including “match start time, end time, map, mode, result, kills, deaths, assists, score, shots fired, hits, damage done, damage taken” and a “Skill” value.
Source: PC Gamer, January 2025
https://www.pcgamer.com/games/call-of-duty/activision-will-send-you-alarmingly-detailed-data-for-every-single-call-of-duty-match-youve-played-in-the-last-4-years-if-you-ask-and-players-are-using-it-to-figure-out-their-mysterious-sbmm-rankings/
TechSpot also reported that Activision data exports included granular gameplay information such as “player position, movement, weapons used, shots fired, kills, deaths, assists, damage dealt and received” as well as a skill rating.
Source: TechSpot, January 2025
https://www.techspot.com/news/106321-activision-keeps-frighteningly-granular-data-call-duty-gameplay.html
However, recent subject access request exports appear to no longer include that match-level data. My own recent export contains account, subscription, COD Point/token, promo-code and marketplace inventory data, but no match history, no server history, no per-match stats, and no skill/MMR values.
If that data was removed from SAR exports, Activision should explain why.
Most importantly, the missing Experimentation Methods paper could answer the question players actually care about:
What is Activision optimizing for when it changes matchmaking?
Is it optimizing for:
- lowest ping?
- fair skill distribution?
- fast queue times?
- retention?
- engagement?
- quit rate?
- store interaction?
- match completion?
- “fun” as measured internally?
- some weighted blend of all of the above?
Activision already says it monitors player-focused KPIs:
> “We track a number of player-focused key performance indicators (KPIs) including: hours-per-user, quit rate, retention/churn, and survey results.”
Source: Activision Research, Matchmaking Series: Ping, p. 2
https://research.activision.com/content/dam/atvi/activision/atvi-touchui/research/publications/docs/Call-of-Duty-Matchmaking-Series-PING.pdf
That is exactly why the experimentation paper matters.
If matchmaking experiments are being run on live players, the community deserves transparency on:
- what variables are changed
- how test/control groups are selected
- whether experiments differ by playlist, region, skill band, party size, or platform
- whether Warzone has different matchmaking experiments from core multiplayer
- whether experimental changes can affect ping, lobby difficulty, team balance, or server region
- how Activision decides a matchmaking change is “better”
I am asking Activision to finish the transparency they announced.
If Experimentation Methods was cancelled, say so.
If Warzone uses the same matchmaking principles as core multiplayer, explain how those principles apply to Resurgence and Battle Royale.
If Warzone uses different rules because of squad size, server population, redeploy mechanics, Casual/Normal/Ranked playlists, or regional capacity, explain those differences.
If match-level data and skill ratings were removed from subject access request exports, explain why.
And if the answer is “we cannot share more because it would make matchmaking easier to manipulate”, then say that plainly too.
Tagging /u/CallofDutyCM because this is a genuine community transparency question.