College Basketball Betting–The Insignificance of NCAA Tourney Line Moves


One of my favorite movies is ‘The Matrix’. It’s a great movie for a lot of reasons but it provides a perfect example here. Trying to understand line movements is an acquired skill. You learn how to do it the same way they learned to stare at binary code cascading down a screen and see threats and attackers. Theory will only take you so far—the rest is a function of experience and the intuition it develops.

On balance, too much is made of line movement in sports betting. It’s important but only in aggregate—you have to stare at ‘the screen’ every day and it’ll begin to tell you things. But that’s the province of professional sports bettors. On a micro level it’s pretty much irrelevant. There’s just not that much you can learn from the line movements on an individual game. The bigger the ‘public’ betting interest in a game, the less revelatory the line movements on it will be. And that means that the less significant it will be for your point spread bets.

With few exceptions (the Super Bowl and the Champions League Soccer Final) you won’t find a more ‘public’ event than the NCAA basketball tournament. The first weekend of the tournament is the biggest betting event of the year (depending on what part of the world you live in, the Super Bowl and Champions League Final has a bigger one day handle). While sharp players can find value in NCAA tournament betting, it’s mostly ‘square’ money. The deeper we go into the tournament the less value there is to be had.


Once we get into the ‘Sweet Sixteen’ and ‘Elite Eight’ you’ll learn more from contacting an astrologer than you will from March Madness line moves. Here’s why NCAA basketball line moves just don’t matter—and particularly in the later stages of the tournament:

A Small Line Movement is Statistically Insignificant In Basketball: Looking at the opening numbers in the 2016 ‘Sweet Sixteen’ there were four games. None moved by more than one point from the opening number. A point or two isn’t significant in college basketball and this movement tells you nothing. Had you followed the line moves you’d have gone 2-2. Obviously, you should always bet at the best price you can find but from a predictive standpoint these type of moves are useless.

Too Much ‘Public’ Money: What recreational players often fail to realize is that all line moves are not created equal. The source of a line movement is much more important than the number of points it moves. If I’ve got a ‘source’ at a sportsbook that tells me that ‘certain sharp players’ are on a game and it moves by ½ point that’s more significant than ‘square money’ moving a line several points. By the ‘Sweet Sixteen’ and ‘Elite Eight’ most ‘sharp players’ are looking elsewhere for value. This isn’t to say that you can’t find value by going against the public if they move a line too enthusiastically—just that public money moves aren’t significant from a predictive standpoint.

Sportsbooks Move Lines ‘On Air’: In the glory days of Las Vegas sports betting bookmakers set their own line and stood by it. In the days before live odds feeds were commonplace the only way to ‘shop points’ was by foot and you’d often find a difference in a point or two just by crossing the street. Things are different now and too many bookmakers are too concerned about what other people are doing.

This can create downright absurd situations—a couple of years ago I was at a Las Vegas sportsbook that shall remain nameless. It’s one of my favorites in town and I generally respect the management so I’m not looking to ‘out’ anyone. I was talking to the book manager about a Final Four game. The manager said that 90% of his bets were on the favorite, yet he was moving the line the other way—toward the dog which in theory would attract even more money on the chalk. When I asked why he simply responded that he couldn’t take the chance of risking exposure due to a ‘rogue line’. He was content to be heavy on the favorite rather than even risk the chance of getting a flood of money on the other side by hanging a price out of line with the rest of the sportsbooks on ‘the screen’. The ‘higher ups’ can better accept a losing night at a price at the everyone else had than they can one that was out of sync with other books. Never mind that this flies in the face of sound bookmaking theory which suggests that lines are moved in response to betting action.

There are no short cuts to sports betting success. If winning was as easy as waiting for the line to move by a half point and betting accordingly, the books would go broke. It’s not that easy and you’re doing yourself a serious disservice if you think that it is.