Is Vegas Underrating The Warriors?


Our NBA playoff projections, which are based on a version of Jeremias Engelmann and Steve Ilardi’s Real Plus-Minus ratings (RPM), give the Golden State Warriors a 48 percent chance of winning the NBA title. Other statistical systems hold the Dubs in similarly high regard: The playoff probabilities at Basketball-Reference.com give them a 47 percent chance of winning a ring, and John Hollinger’s playoff odds put their chances at 38 percent.

Gambling markets are more skeptical of Golden State. According to PredictWise, which compiles odds from Betfair and removes the “vig” (house cut), bettors have the Warriors with a 27 percent chance to win the title. And a number of sportsbooks consider LeBron James’s Cleveland Cavaliers to be the title favorites.

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So here’s a gut-check. The Warriors, with a 67-15 regular-season record, are the top overall seed and will have home-court advantage throughout the playoffs. How often does the top overall seed5 win the title?

The answer — since the NBA expanded the playoffs to 16 teams in 1984 — is 45 percent of the time, almost exactly the chances RPM assigns to the Warriors. The top seed has won 14 titles in 31 attempts.

YEAR TEAM REGULAR-SEASON RECORD WON TITLE
1996 Bulls 72-10
1997 Bulls 69-13
1986 Celtics 67-15
1992 Bulls 67-15
2000 Lakers 67-15
2007 Mavericks 67-15
2008 Celtics 66-16
2009 Cavaliers 66-16
2013 Heat 66-16
1987 Lakers 65-17
2006 Pistons 64-18
1985 Celtics 63-19
1989 Pistons 63-19
1990 Lakers 63-19
1991 Blazers 63-19
1994 Sonics 63-19
2012 Spurs 50-16
1984 Celtics 62-20
1988 Lakers 62-20
1993 Suns 62-20
1995 Spurs 62-20
1998 Jazz 62-20
2005 Suns 62-20
2011 Bulls 62-20
2014 Spurs 62-20
2002 Kings 61-21
2004 Pacers 61-21
2010 Cavaliers 61-21
1999 Spurs 37-13
2003 Spurs 60-22
2001 Spurs 58-24

And the Warriors, with 67 wins, are better than your average top seed. Since 1984, nine other top seeds have finished within two games of the Warriors’ regular-season win total (somewhere between 65 and 69 wins). Those teams went 7 for 9 in winning titles. In contrast to the single-elimination NCAA basketball tournament, the best-of-seven format in the NBA playoffs has historically allowed elite teams to rise to the top.

We certainly do not recommend you naively trust statistical systems ahead of the handicappers. Vegas is really tough to beat. Gamblers can account for all the information in systems like RPM — plus whatever other data they think is relevant, like postseason experience or how teams match up with one another or the San Antonio Spurs beating the odds again and again.

Still, we’re a little more likely to give credence to complex systems like RPM when they’re also able to pass simple gut-checks like this one.