Jackie Robinson Day (Re-estimated)

When major league baseball held its opening day on April 15 in 1947, a 28 year-old infielder made his highly-anticipated debut at first base for the Brooklyn Dodgers. He would go on to record an extraordinary season and career worthy of induction into the Baseball Hall of Fame, winning Rookie of the Year honors in 1947, a batting title and Most Valuable Player award in 1949, and a World Series title in 1955. He also produced two seasons that rank among the top 100 ever (by the metric of Wins-Above-Replacement among position players).

Jackie Robinson (1954 public domain photo by Bob Sandberg for Look Magazine).


Looking at the box score, Jackie Robinson didn’t make an overwhelming impact on the outcome of his first game, but his presence on the field challenged the racist status quo of professional baseball and American society. What’s more, the intense public-ness of the challenge made Robinson’s presence a symbol and a spectacle: of the roughly 26,500 spectators in attendance at Ebbets field, an estimated 14,000 were black. I cannot imagine what it was like to be at that game — one of those rare places and moments where it becomes possible to see an historic social transformation as it unfolds. Just the thought gives me goosebumps.

Every major league player, coach, and umpire will don Robinson’s iconic number 42 in recognition today. Watching games and highlights from Jackie Robinson Days past, I’ve been troubled by how easily such observances drift into a hagiographic reverie that sometimes even take on a self-congratulatory tone. Stories of Robinson’s incredible athletic and personal accomplishments sometimes efface his struggle against horrible, violent, and aggressive responses. Worse yet, the stories usually play down the persistence of racism and its effects today. Baseball celebrates Jackie Robinson Day out of a strange combination of guilt and pride; knowledge and ignorance; resistance and complicity.

As I indicated earlier, Robinson’s performance and impact qualified him for the Hall of Fame along multiple dimensions. However, another way to think about his unique contribution to baseball is to consider how such virulent racism likely affected his play and how unbelievably, mind-blowingly great a player he might have been under less racist conditions.

There’s no obviously valid way to construct a counterfactual Jackie Robinson, but research on the phenomenon of stereotype threat suggests a very simple, naive statistical adjustment strategy. To paraphrase a bunch of scholarly studies and the (pretty extensive) Wikipedia article, stereotype threat reduces the performance of individuals who belong to negatively stereotyped groups, largely by inducing feelings of anxiety.

Stereotype threat affects various kinds of behaviors including athletic achievement. A 1999 study by Jeff Stone and colleagues (pdf) estimates the effects of some typical forms of stereotype threat on a sample of black men’s athletic performance, reporting that race-based priming resulted in a 23.5% worse outcome on a miniature golf (!) task than a control condition with no priming.

Consider that the priming in this Stone et al. study was done in a fairly polite, impersonal, non-hateful, non-threatening way in relation to a mini-golf task with absolutely nothing at stake. Consider just how personal, vitriolic, and violent the responses to Jackie Robinson were — many of them coming directly from opposing players and “fans” who went to great pains to heckle him in the middle of at-bats, physically target him with violent slides and more on the field, or issue death threats to him and his family. Consider how much Robinson had at stake and just how public his successes and his failures would have been.


Some people may like to imagine (and filmmakers may like to depict) that the hatred helped to motivate and focus Robinson, spurring him to even greater performance. Similarly, part of the mystique of the greatest athletes is that they seem to empty their heads of all the noise and distractions that would debilitate the rest of us at precisely those moments when the stakes and pressures are highest. It’s easy to say that Robinson didn’t respond to the pressure in the same way as most humans would, but the research on stereotype threat suggests that it probably affected him on the field anyway. Just being reminded — even in very subtle, socially-coded ways — that you belong to a socially excluded group reduced athletic performance by nearly a quarter. The sort of cognitive burden that comes along with being singled out and targeted by the kind of racial hatred that Robinson experienced must be orders of magnitude greater. What sort of impact would this burden have had on Robinson’s play?

Now, go look at the stat lines again from those two spectacular seasons (1949, WAR 9.6,  and 1951, WAR 9.7) that Robinson had and imagine them without the stress, the pain, the distraction of all that hate. Be a little bit generous and inflate the WAR statistics by the same 23.5% that Stone et al.’s subjects performance dropped in a laboratory study in ridiculously low-key conditions. Under these assumptions, Robinson’s two greatest seasons might have yielded WAR of 11.9 and 12.0 respectively — easily placing them both among the top 10 seasons by a position player ever.