How analyzing betting lines could benefit a fantasy owner

Friday September 6th, 2013

Miles Austin made 66 receptions for 943 yards and caught six touchdowns for the Cowboys last season.
Greg Nelson/SI

As is the case for so many of you, I like to read. A lot. I enjoy reading about topics in which I already have an interest, and in others where I don't but the story sounds enticing. Most of all, I love reading something that makes me smarter. I love reading a column that takes a well-researched item, like fantasy football, for instance, and puts it in a new light. Without getting too preachy, that's exactly what we'll try to do in this space all year long.

Every Friday for the 2013 season, we'll look at fantasy football from a previously unexplored or underutilized angle. One week it might be film study. The next it could be a focus on advanced stats. Or, like this week, we could take our cues from Las Vegas. No matter how it manifests, this column will always pick around the edges of the fantasy football landscape, turning over stones that some others might leave untouched. You may not agree with everything, but hopefully you will be entertained and start thinking about this silly little game we all love in different ways.

One of the most interesting lines this week is fittingly on one of the most interesting games. At press time, the Cowboys are 3.5-point favorites over the Giants. The line opened at Dallas -3, and ticked up a half point in the last 10 days. In and of itself, that isn't the least bit interesting. What is interesting, however, is that approximately 55 percent of the betting public is on the Giants, meaning the line is moving against the money.

Before we get to the importance of that shift, a quick primer on betting lines. If you have any experience with sports gambling, this won't be anything new. In general, casinos (or your local bookie) want 50 percent of the action on each side of a bet. Thanks to the juice, essentially the commission on a bet, the house is guaranteed a profit in this scenario. That means if more money is coming in on one side of a bet, such as it is with the Giants, the line will move in that direction. The Giants started at +3 and money has been coming in on them. In a normal situation, they'd slide down to +2.5. If the money kept coming in, they could get down to +2 or +1.5. That would convince more people to bet on the Cowboys, and get Vegas closer to its 50-50 ideal.

Sometimes, though, Vegas likes to make a bet itself. If it wants money on a certain team, it will encourage the public to play that side by making their line more favorable. That's exactly what is happening here. Despite 55 percent of the public betting on the Giants, the line suggests they are a greater underdog today than they were at the start of the week. In other words, Vegas is actively trying to get even more action on the Giants. That's akin to the oddsmakers saying, "We like the Cowboys."

Information like this can be especially helpful when making that tough start 'em, sit 'em decision. That's always going to be a hard call, because the two or three players you're considering for a starting position are necessarily close to each other in the rankings. Knowing how a line has moved can help a fantasy owner anticipate how the game will unfold, and that in turn can help make the decision a little easier.

In our Cowboys-Giants scenario, we know that as it stands right now, Vegas likes the Cowboys. We also know that with an over/under of 48.5, the betting world is expecting a high-scoring game. This makes Miles Austin a better fantasy play this week than he might appear. The Cowboys will need to score three or four touchdowns to win a game played in the high-20s or low-30s. That will give Austin, who's a fringe starter this week, plenty of opportunity to make an impact. It could also give you more incentive to start Eli Manning. There's no better place for your fantasy quarterback to be than chasing down points in a shootout.

By the time this game rolls around Sunday night, the line could have swung back in the other direction. A ton of money could come in on one of the teams, forcing the oddsmakers' hand. If you're going to try to use this to your advantage, make sure you watch the line all the way up until the moment you have to set your lineup. Understanding line moves may not help you every week, but if it helps you win just one game, it could make all the difference.

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