Another sign of the gradual ascent of statistical analysis within sports: some NBA players now employ a personal statistician.

Justin Zormelo, a 30-year-old Georgetown graduate, is at the forefront of a growing industry, his services a must-have accessory for the playoffs. Zormelo, who spends hours every day hunkered over a laptop in his home office, has become the go-to source for players who want a private guide through the emerging world of advanced analytics.
Let others conduct wind sprints and weight-room sessions. Zormelo, who works for individual players and not their teams studies film, pores over metrics, and feeds his clients a mix of information and instruction that is as much informed by Excel spreadsheets as it is by coaches’ playbooks. He gives players data and advice on obscure points of the game — something many coaches may not appreciate — like their offensive production when they take two dribbles instead of four and their shooting percentages when coming off screens at the left elbow of the court.
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Zormelo’s career took off three years ago when he began working for Kevin Durant, the league’s leading scorer and most valuable player. Zormelo spent last season living out of two suitcases in Oklahoma City as Durant’s full-time stats guru. He attended Thunder games with his iPad in tow, watched film with Durant at night and even slept on Durant’s couch. Zormelo ended their season together by presenting Durant with a five-page report full of pie charts and bar graphs.
This season, Zormelo worked with All-Stars like Paul George of the Indiana Pacers, John Wall of the Washington Wizards and Rajon Rondo of the Boston Celtics. At least three of his clients are still in the playoffs. When they require hands-on involvement, he heads to the airport.

One of the chief challenges for teams that employ quantitative analysts is getting the coach and players to embrace the recommendations that come from the analysis. It's a good sign for those teams when players themselves are turning to the numbers for self-improvement, though the conflict between recommendations from a player's own statistician and the team's analysts can be troubling.

Fluid team sports like basketball are trickier from a strategic standpoint than a sport of individual confrontations like baseball. In baseball, individual statistical achievement and team achievement are usually highly correlated. In basketball, one player may pad their scoring stats by shooting a lot, but that may not be best for the team.

Atul Gawande once wrote a great article about how most of us could benefit from more coaching. It seems that one of the greatest investments for someone with wealth would be coaching, and yet I don't observe that happening.

I suspect that the people hire coaches when the marginal value of the coaching is very clear, and that tends to be in areas where the price or market signals are explicit and efficient. Athletes have very public contracts, their statistics are tracked at an increasingly fine resolution, the correlation between improved play from coaching and both team success and personal financial wealth is visible and clear.

Many people hire fitness coaches because they can see the results on the scale each morning, or in the bathroom mirror, and in society's well-documented preference for people who are fit.

Hiring a coach for your professional career may have greater returns, but the signals may not be as consistently reinforced or even as measurable as for an athlete, and where do you find a good coach anyhow when the labor market is so tight? Given that the practice is not common in many disciplines (take product management as one example) there is real inertia that means most practitioners have to own their own development.