# From Theory to Tabletop: The Accuracy of Elo Predictions in Warhammer 40K’s Las Vegas Open 2024

This week Jeremy from Stat Check drops in to cover Hammer of Math with an update on Elo scores and how they impacted (and were impacted by) the 2024 Las Vegas Open tournament.

Jeremy aka Curie from Stat Check here with a little Elo check-in following LVO 2024.

Last month we had an introductory article from Stat Checkâ€™s Cliff Thomas wherein he laid out how the Elo system that the team here at Stat Check have been developing over the last couple years. Now that we have 2 full years of data starting from February 2nd 2022 up until this weekend, we decided to take a stab at evaluating the systemâ€™s accuracy.

### Elo Predictions in Warhammer 40k

The premise here is simple – as Cliff laid out in the above article Elo gives us an estimate of a player’s skill at the game. Relative differences between two player’s Elo scores gives us an idea of how likely one player is to win over the other – the larger the gap, the more the higher-ranked player is favoured. We took this theory and put it to the test for LVO 2024. The current Elo rankings (LVO 2024 should be integrated very shortly) can be found here.

### Las Vegas Open 2024

Frontline Gaming’s Las Vegas Open is the largest competitive Warhammer 40k event of the year, and serves as the culmination of the International Tournament Circuit (ITC) season. It welcomes players from across the globe, and even with attendance dipping slightly this year, still had over 900 players attending the 40k Champs event. These 907 players competed in 2,588 games, and we’re going to see how well Elo predicts the outcome.

### Elo Prediction Accuracy

Let’s kick things off with a simple analysis – across how many games did the higher-ranked player win? The table below shows exactly this, with the difference in Elo ranking put together in buckets of 25 points. As you can see, the greater the difference between players’ rankings, the more likely that the higher ranked player wins. More interestingly though, across the whole data sample, Elo scores correctly predict the game outcome 65.8% of the time.

Elo DifferenceNumber of GamesPercentage of Games Won by the Higher Ranked Player
0 to 2578052.9%
25 to 5055863.3%
50 to 7535265.6%
75 to 10024869.8%
100 to 12514678.1%
125 to 15012583.2%
150 to 17510182.2%
175 to 2008076.3%
200 to 2256377.8%
225 to 2504588.9%
More than 2509092.2%
Grand Total258865.8%

More interestingly, the results also align with the theoretical win distributions for Elo quite well. As an example, for an Elo difference of 200 points, the expected result is that the higher-ranked player will win 75.9% of the time, while the LVO 2024 data shows that this is between 76.3% and 77.8%.

### The Top 8

Coming to the final day of LVO 2024, we were left with 8 players vying for the championship title, presented below with their detachments and their Elo score going into the final day:

• Ben Cherwien – Black Templars (Firestorm Assault Force) – 1935.6
• Folger Pyles – Aeldari (Battlehost) – 1856.4
• Matt Lorah – Necrons (Hypercrypt Legion) – 1823.5
• Sweet Lew – Leagues of Votann (Oathband) – 1812.8
• Daniel Olivas – Aeldari (Battlehost) – 1811.4
• Samuel Pope – Tyranids (Unending Swarm) – 1779.4
• Charlie Andre – Chaos Space Marines (Slaves to Darkness) – 1752.8
• Richard Cozart – Astra Militarum (Combined Regiment) – 1698.2

Across the seven games that followed, five of them were won by the higher ranked player. The two exceptions to this were Daniel Olivas’ win over Ben Cherwien, and the 2024 LVO Champion Matt Lorah’s grand finals win over Folger Pyles. In the first of these games, Ben was ranked considerably higher than Daniel – he was favoured to win the game by a 2 to 1 odds. Conversely, Matt Lorah and Folger Pyles were very close in their respective rankings, with the odds being 6 to 5 that Folger would win the round.

### Future of Elo Predictions

That wraps up our quick look at how Stat Check’s Elo system worked at predicting the outcome of games at LVO 2024. Going forwards, our team at Stat Check is looking to refine this metric and provide a more readily accessible tool for players to view their stats as well as their opponents*.

*Yes we’re aware how ugly the current page is!

Have any questions or feedback? Drop us a note in the comments below or email us atÂ contact@goonhammer.com.Â And don’t forget to check out the excellent work the Stat-Check guys are doing overÂ on their website.