How to (maybe) hack the NBA over/unders
Uncovering the Championship Hangover Effect and other betting insights.
OK, maybe not hack, as in, you’ll win all your bets if you read this post. I think you’ll enjoy this in the same way that that jar-opening hack I saw on Instagram doesn’t work every time, but man it sure is nice to know.
Anyway, the NBA season starts in less than a week! Which means it’s officially time to pee on some trees!
Yeah, I said pee on some trees. ‘Tis the season where NBA writers/analysts like myself do their best golden-retriever impression, lifting their legs and marking their territory so they can gleefully come back and say “I told ya so!” when one of their breakout/bust picks goes well. When it doesn’t pan out, we scrub those trees dry and pretend like it never happened.
To this point, I have a suggestion: if you’re an NBA fan or just a numbers nerd and haven’t subscribed to Nate Silver’s newsletter – cleverly titled Silver Bulletin – then head over now and smash that subscribe button.
The whip-smart mind behind FiveThirtyEight.com is now at Substack and has studied the NBA in-depth over the past few seasons mostly because he’s a big NBA junkie but also, I’ve learned, it’s because he’s writing a book about gambling. With his hind leg in air, Nate has kindly shared his betting-focused views on each of the 30 NBA teams with helpful color-coded keys. The result is a comprehensive and delightfully-nerdy 10,000-word NBA preview that I’ve come to miss in today’s NBA coverage. (Man, I used to tear through those Basketball Prospectus tomes back in the day).
I had already planned to share my three favorite OVERs and three favorite UNDERs for this upcoming season. But Silver’s preview inspired me to do it with a little twist: I’m going to make these picks almost purely due to over/under historical trends and not because of any nitty-gritty player opinions, which, if you want, you can find plenty of other places. This post is more forest than trees (OK, enough botany metaphors).
So here’s what I did. I downloaded 23 years worth of Vegas over/under data at the handy sportsoddshistory.net and crunched the numbers dating back to 2000. I removed the COVID-scarred 2019-20 season and prorated the 2011-12 and 2020-21 shortened seasons so everything is on the same scale. For this year’s over/unders, I’m using the DraftKings lines found here.
The first little study:
Do some teams typically outperform or underperform Vegas?
(I’m using “Vegas” as a short-hand for bookmakers even if that term is collecting dust.
Here’s what I found:
Lots to chew on here.
The teams on the right tend to outperform expectations (cash the over on Vegas’ win projection more than 50 percent of the time). The vertical axis represents the average of the actual wins above/below the Vegas line. For example, the Pelicans have 6 OVERs and 14 UNDERs for a Over Pct of 30 percet and an average of -1.8 wins compared to the projection. Not great, Bob! (For those wondering, those teams sitting on top of each other in the middle of the chart: Toronto, Portland and Boston.)
I have a bunch of these charts/tables, which I’ll share later on in the post. But I’m going to make my first pick based on the above chart.
UNDER Clippers 46.5 wins
So here’s something crazy: the Clippers are 3-13 against the over/under line dating back to the Mike Dunleavy era. The only times the Clips cashed the over: 2020-21, 2018-19 and 2012-13. The rest? It’s a bloody mess. They finished 8.5 games under last season’s 52.5 line and 3.5 games under the 45.5 line in 2021-22. In essence, if you think the Clippers are going to be three games better than they were last season and five games better than the year prior, go for it. I’m just not buying it. (And look at Vegas’ unofficial team, the Lakers, dragging at the bottom of the chart, too)
Aside from the historical evidence, the Clippers have to manage Kawhi Leonard and Paul George’s workloads again, which makes the Clippers a pretty reasonable under bet. At this year’s media day, Kawhi expressed rarely-seen defiance on the new Player Participation Policy, suggesting that his DNP-Rests won’t be going away anytime soon. While the Clippers might swing a deal for James Harden, he’ll have to play himself into game shape and acclimate to the new environment. Plus, as masterful as Ty Lue is in the playoffs, he’s underperformed in four of his five full seasons as the head coach in the study. I’m out on the Clips, whose core might be the oldest group in the NBA.
And now a pick that might surprise you …