One of the things you hear a lot is to make sure you’re always getting the best number. I’m guilty of it, and I’ve never broken down how it’s done historically, because there isn’t really readily available opening line data out there. Paying attention to big line moves sometimes is smoke and mirrors. Big bettors can manipulate the market on a Thursday to move lines so they can come back later at higher limits and bet the other side on Saturday. If you have perfect information, you could track these types of plays. For my analysis, all I’m really concerned with is how would you do if you bet these big line moves. For example, if Oregon opened -7 against Stanford and got bet up to -10.5, historically, are you better off following the move or fading it?

I pulled the data for the last 5 seasons. I decided to start with a minimum 2 point move from open to close after seeing an exchange on twitter on Adam Kramer’s timeline (h/t @SkatingTripods). There were 1301 games that had a line move of at least 2 points from open to close (based on consensus open/closing lines most books would have offered). Simply betting the closing line and tailing the move would have resulted in a 692-609 record ATS (53.19%) and assuming -110 odds, would put you up 22.1 units over that time. Several sportsbooks offer reduced juice, so you could potentially do even better at shorter odds. Below is the list of each team’s record ATS given the above scenario.

What about bigger line moves? There were 658 games that had a line move of at least 3 points from open to close. Tailing the moves again is profitable and at a little larger percentage going 352-306 ATS (53.50%). However, once you get to 4 points or higher, the results get a little random partly due to a smaller sample size of games and my assumption that some of those big moves could have been artificial, an injury or suspension announced midweek, etc.

Pretty interesting stuff. Had you done this each of the past 5 seasons, only last year would have resulted in a losing season. I’ll definitely circle back to this during the season to see how things play out during 2014.