Analytics Stories

CHAPTER 17Some Sports Have All the Luck

Most of us think our sports teams are cursed with bad luck. Certainly Franco Harris's “immaculate reception” (watch it here /www.youtube.com/watch?v=dHIXFKrrUhA) was a lucky play for the Steelers and unlucky for the Raiders. In this chapter, we investigate a controversial topic: Among the NFL, MLB, NBA, NHL, Men's Olympic Basketball, Premier League Soccer, and the Premier Lacrosse League, which leagues have plays that involve the most skill (or least luck)?

Skill vs. Luck: The Key Idea

Senior Database Architect of Stats for MLB Advanced Media analyst Tom Tango was the first person to approach this knotty problem (see www.wired.com/2012/11/luck-and-skill-untangled-qa-with-michael-mauboussin/). Michael Mauboussin brought more attention to this issue in his book The Success Equation (HBR Press, 2012). The basic idea presented by Tango and Mauboussin is embodied in the following equation:

Most investigators have defined outcome as the fraction of games a team wins in a season (see, for example, (statsbylopez.github.io/NESSIS2017_files/NESSIS_2017.html).

I prefer to try to understand the fraction of a sport's outcome that is luck by looking at the result of every game during a season. The data I use for each sport is the margin of victory in each game and two teams playing in the game. Then I use multiple regression (see Chapter 16, “What's ...