# NBA Betting Strategy: Christmas Betting System

Jason Lake

Friday, September 20, 2013 8:23 PM UTC

Friday, Sep. 20, 2013 8:23 PM UTC

If you’ve been betting on the NBA for a while, you might have noticed the return of an old favorite – but with a few new wrinkles.

Everything has a beginning, a middle, and an end. Take the NBA regular season, for example. The first couple of months, teams are still getting used to new players and new schemes. Then, right around Christmas time, the games get really, really good – until the last few weeks, when injuries and tanking can really mess up your basketball betting mojo.

This fact of tripartite life has become so entrenched that the regular season might as well start with the Christmas Day quintuple-header. That’s the way some sharp NBA betting minds used to think. They even had a thing called The Christmas System, where you’d do some math with the winning percentages of Team A and Team B to come up with an approximate NBA point spread. Well, last year the Christmas System came back with a vengeance. And a twist or two.

Under the Tree

You first heard about the Christmas System ‘round these parts last December, when David Schwab let us in on the return of this classic NBA betting scheme. In short, once each team has played about 20 games or so (people hate to wait until Christmas to open their presents), you subtract the winning percentages of your two teams, divide that by 20, then add or subtract three points from the favorite, depending on who has home-court advantage.

Once you have this hypothetical basketball point spread on the favorite, you compare it to the actual point spread. If the actual spread is at least 10 points smaller, bet the favorite. It’s a fairly rough-and-tumble way of discovering undervalued favorites; Schawb lays out some of the other preconditions that have to be met before the Christmas System comes into play. You should give it a read.

Christmas System II: The Quickening

Things get a little trickier if you want to play the underdog. Schwab briefly touches on this scenario, but let’s take an extra moment and look at a specific example of the Christmas System where a team that’s getting points on the actual NBA line is suddenly laying points. And for that, we go back to Xmas Day 2012, when the New York Knicks visited the Los Angeles Lakers as 4-point road dogs.

On Christmas Eve, the Knicks were crushing it in the Eastern Conference at 20-7 SU, or .741, while the Lakers were clinging to life in the West at 13-14, or .481. Using the Christmas System, we subtract those two percentages (forget the decimal point) and get 260. Divide by 20 to get 13, then give New York three fewer points for playing at Staples. Your kayfabe NBA point spread for this matchup: Knicks –10. That’s a play on New York.

That’s Amare

Well, not quite. One of the preconditions of the Christmas System is that the team you’re following cannot be missing an injured starter, and the Knicks were without Amare Stoudemire that day. Kurt Thomas got the start instead, and New York lost 100-94. D’oh!

Now, the funky part of this Xmas trick, at least as I understand it, is you don’t need to look for a 10-point gap when you’re playing the underdog. Any situation where the real dog becomes the System favorite will do, in theory, even if it’s only from NBA odds of +1 in real life to –1. But you’ll definitely want to exploit this market inefficiency more when there’s a larger gap involved – same goes for the favorites, as well.

You’ll also find that adding the OVER to your NBA picks can be profitable when you identify qualifying favorites using this system. According to my good friend Bob Harvey, looking at the four seasons between 2007 and 2010 inclusive, favorites were 33-22 ATS and the OVER was 31-22-2 using the Christmas System. When the favorite was laying at least five points, that record improved to 17-9 ATS and OVER 18-7-1. Happy Holidays!
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