Carlsen vs Nakamura: Who Science Says Will Win

In boxing there was Ali vs Frazier; in tennis, Navratilova against Evert.

In online chess there is Carlsen vs Nakamura.

Although World Champion GM Magnus Carlsen and four-time U.S. champion GM Hikaru Nakamura have not rumbled in the jungle or played each other for 14 grand slam titles, they will meet on October 27 in the Grandmaster Blitz Battle Championship. The two will duke it out for the undisputed title of best online chess player.

Before diving into a statistical analysis of the players, let's recount how the players got to this point. 

Carlsen has outscored his two opponents—GMs Tigran Petrosian and Alexander Grischuk—by 37-12. Nakamura has faced stiffer competition in GMs Pentala Harikrishna and Maxime Vachier-Lagrave, and holds an impressive 37.5-19.5 record.

The Chess.com community voted Carlsen as the overwhelming favorite to take home the inaugural GMBB title, likely a nod to the Norwegian's over-the-board dominance against Nakamura. Yet as any blitz and bullet aficionado can tell you, results made in classical time controls generally have no bearing on speed chess matchups. Online chess is an entirely different beast.

Chess has lacked the advanced metrics of a sport like baseball—until now!

Chess.com's director of research Roland Walker and data analyst Gerard Le-Marechal have conducted groundbreaking research, discovering statistical principles that exist across millions of games played, to devise CAPS, the Computer Accuracy & Precision Score. CAPS is a revolutionary tool that provides a holistic analysis of a player's abilities, taking into account individual moves within the context of the position rather than just reacting to results. On an ascending scale, the logic is simple: the higher your CAPS, the more accurate you are.

Without further ado, let's investigate how the two competitors stack up.

1. Magnus Carlsen is the best classical player in history.

There is a timeless debate about whether or not champions of past generations are better than Magnus. There's no longer an argument to be made: Fischer and Kasparov fans can tip their caps to Carlsen's CAPS. 

2. Hikaru is much more precise than his FIDE rating indicates.

Nakamura's live rating has dipped below 2780 for the first time in 20 months. Yet the Olympiad gold medalist boasts a CAPS score of 98.32 over the past year in classical time controls, putting him in striking distance of the world champion. Notice the CAPS-projected Elos are very high; being a historical statistic, FIDE Elo lags in responsiveness as you change in ability. At the elite level, being even a little bit more accurate directly correlates to a large increase in strength.

3. Blitz hurts both players' performance, but Carlsen's more.

When only over-the-board blitz games were taken into account, there is a noticeable decrease in accuracy. Carlsen's CAP from the last year was 2.335 lower in blitz chess than classical; Nakamura's drop was less precipitous, at only 1.405.

4. Keeping up with the math.

Over the last year, Carlsen has played more precise classical chess than ever. Nakamura has not been too shabby either (his CAP of 98.32 over the last year dwarfs his professional average of 97.97). But blitz is a Nakamura specialty, as evidenced by his record CAPS in that format.

5. Nakamura is more accurate during online blitz games, too.

We analyzed the quarterfinal and semifinal matches, and found that Nakamura rarely makes mistakes. Granted, sometimes players are spoon-fed good moves by their opponents, but here it is wise to trust the player. Carlsen actually played fewer moves during the first two rounds, but made more than double the inaccuracies and nearly triple the blunders.

6. What scores do not tell you: who has played more accurately in every time control.

If we were to use baseball slash lines, Carlsen's would be 96.93/95.31/93.45 CAPS with respect to the five-, three-, and one-minute time controls. Nakamura has a line of 97.19/97.03/95.20 CAPS. The longest time control has been the most level, but as the clock ticks down, Nakamura's chances increase.

7. What the numbers do not tell you.

Hikaru has played more accurately thus far, at least when we consider blitz, but the numbers can be deceiving. Context is always important; for instance, Magnus beat Petrosian 21-4, so at a certain point he might have relaxed and lost concentration, particularly in the bullet segment. With a relatively small sample size, every game has a large impact. Nakamura played some of the best speed chess ever recorded against Vachier-Lagrave, but psychology against Carlsen might prove a large factor.

Carlsen's CAPS actually increases when he plays Nakamura, whose CAPS decreases against Carlsen.

8. The world championship

...of online chess. The Grandmaster Blitz Battle Championship is important to both of these players, who have a heated rivalry. Carlsen has a massive plus-score against Nakamura, but Chess.com is more comfortable terrain for the speedy American. Nakamura recently beat Carlsen for the first time in Bilbao, so rest assured he wants to continue that trend and end the psychological spell the Norwegian has cast on him.

Bonus

It would not be right to reveal our CAPS analytics to you without poking fun at IM Danny Rensch. He really struggles at playing while providing commentary.

Will Carlsen hold anything back considering he takes on Sergey Karjakin for the classical world championship in just three weeks? Will the world champion continue his dominance over Hikaru Nakamura, or will the latter prove to the world that he really is the best blitz player on the planet?

Please give us your predictions in the comments.