The case against zig-zag theory of betting
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Now that all NBA first-round playoff series have finished their openers, many bettors are thinking about one thing…the zig zag!
There are many variations of what’s called “the zig-zag theory” in playoff betting.
- To some, it means skipping the first game, then betting the straight up loser of the prior game against the spread the next time out. The theory is that whoever lost the prior game will be super-motivated to play great, while the winner might make the mistake of relaxing.
- To others, it means skipping the first game, then betting whoever didn’t cover the point spread in the prior game because ATS results should regress toward break-even over time. It’s a fast variation on “the due theory,” with the team that didn’t cover the prior game due to cover this one.
- Old school bettors (some of whom will claim they’re the ones that invented “the zig-zag theory” back in the day) will tell you that you’re supposed to bet the home teams in Games 1 and 3 because the crowds will be extra boisterous, but then bet the previous straight up loser in any other game.
Who’s right? Is there an actual strategy bettors should use that’s very likely to earn a profit?
Look, the market KNOWS about the zig-zag theory. A liquid market is the sum of all models…and that’s one strategy that’s been absorbed into the stew. It may work some years. It’s extremely likely to work in a few series. The trick is knowing in advance which those will be.
Working against the zig-zag (any variation):
- Superior teams have become much more aggressive in recent years about finishing early rounds as quickly as possible. The more good teams rest, the fresher they are when a championship is on the line. If an elite team sweeps a series with big victories, the zig zag takes a bath. If a few do that, good news from more competitive matchups probably won’t be enough to earn an overall playoff profit.
- Three-point shooting is erratic, which is a randomizer that can have a mind of its own. The highs and lows of this dynamic aren’t interested in following along with the zig zag. It’s possible for a team of shooters to be hot or cold for more than one game at a time.
- Betting’s standard 11/10 vigorish works against any strategy. That’s a harder hurdle to clear than most gamblers realize. If your zig-zag bets post a 50/50 record, you lose money. You must hit 52.4% of your bets to break even, and probably at least 54% for a strategy to feel like it’s worth your while.
There will be some bounce backs this week. A few of those are likely to beat the spread by big margins. But that doesn’t mean you should bet every possible bounce back. Sharps focus on team skill sets, and whether or not market prices properly capture those skill sets.
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