# How Betting Lines Work — Super Bowl Example

If you are like me, you are not watching the Super Bowl. If you are like me, you are only vaguely aware of it. I had to be reminded yesterday at 4:00 that it was even happening. And it was only today that I learned that it is taking place here in the Bay Area. It’s not that I don’t follow the news. But when talk turns to sports — most especially football — I just tune out. But I thought it might be interesting to talk a bit about how betting lines work.

This all started because I was talking to Will and he told me that 70% of the action was supposedly on the Panthers. I already knew that the line was Panthers -6. That’s a points line and it means that if you bet on the Panthers, they need to win by more than 6 points. That also means that if you bet on the Broncos, you get 6 extra points. So if they lose by only 5 points, you would win your bet. But when Will told me about all the action on the Panthers, I asked what the line was originally. He told me: Panthers -6. That didn’t make any sense.

When betting lines first come out, they are based upon the work of sports nerds: analysts who crunch numbers to determine how the teams will perform against each other. It will probably not surprise you, given my colorful life, that I used to be one of those guys. (I didn’t do it for sports books, of course; I wrote commercial software that did these kinds of calculations for sports bettors.) So that’s fine. But betting lines don’t stay where they start. They move based upon how the betting is going.

The thing that non-betting people don’t understand (and I assume that describes most Frankly Curious readers) is that the sports books are not at all interested in who wins. When you bet, there is a vigorish or “vig.” That means you bet a dollar, but if you win, you are paid something less, like 90¢. That would be a 10% vig. That’s all the books care about. So they want to have as much money bet on one team as is bet on the other. That’s what the betting lines are all about. Then the books pay the winners with the losers’ money, and keep the vig. It’s a simple and beautiful system.

## Why Betting Lines Move

The initial lines that the sports nerds come up with are not always right. But even if they are, it isn’t a question of how the teams stack up; it is a question of how the bettors think they stack up. So if there is too much money bet on one team, the sports book will move the line in the opposite direction. This is why I asked Will what the starting line was. If 70% of the action was on the Panthers, then the line should have gone up — to Panthers -6.5 or higher still — whatever it took to equalize the amounts bet.

Given that the betting lines didn’t move except maybe at some small books, I have to assume that the 70% number has to do with the number of bets. The books don’t care about that. They aren’t going to change the betting lines over that. What must be happening is that the little bettors are going strong for the Panthers and that the bigger bettors are going for the Broncos. (This doesn’t mean they think the Broncos will win, of course; just that they won’t lose by more than 6.) But if I were a betting man (And I’m not!) I would go with the Broncos, just because I have more confidence in people who are putting big money on the game.

Of course, I don’t know that this is what’s going on. Maybe the big money is on the Panthers, it is just that there is a lot of medium money on Broncos. As I understand it, there are a lot of middle class white folk who don’t like that uppity colored quarterback. And with that, I have gotten as close to the Super Bowl as I care to get.

## Update (7 February 2016 3:36 pm)

I just got email from Will that the line actually did start at Panthers -3. So there has been excessive money bet on the Panthers to move the line to -6. I’m not going to change any of the above, because it is all still valid for discussion’s sake. The fact that the line did move, however, greatly complicates how the books have to manage their bets. This is why they hire really smart people, hoping to get it right to start.

## Update (7 February 2016 3:43 pm)

That makes my “middle class white racist” theory invalid.

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Frank Moraes is a freelance writer and editor online and in print. He is educated as a scientist with a PhD in Atmospheric Physics. He has worked in climate science, remote sensing, throughout the computer industry, and as a college physics instructor. Find out more at About Frank Moraes.

## 16 thoughts on “How Betting Lines Work — Super Bowl Example”

1. I am reading a book and eating chips. That is as close as I get. I would bug you but I thought you were getting your manly on with the game.

• You didn’t really think that! I get my manly on by going on the bus and protecting young women from drunk men. (This was, in fact, the basis of my modern DQ novel. But it has since changed wildly where DQ is a woman — the mother of the narrator.

• I thought men had to refresh their masculinity every so often and that serves about as well as anything else.

I heard that there was a John Lithgow version of DQ on YewTewb. I haven’t watched it yet.

• Apparently there is! I will check it out. But thus far, I have been totally unhappy with cinematic DQs. Although Welles’ where DQ is in the modern world and goes to the movies and attacks the screen is brilliant.

• I watched most of Lithgow DQ last night. There is much to like about it. But it so trivializes the conversations between DQ and Sancho (which is the best part), that it is ultimately disappointing. But the acting is quite good.

• I watched Happy, Texas instead. That was what I was going to bug you about since I enjoyed it and wanted to discuss how remarkable it was.

• Wow. I had not seen that. Welles really got the power of the medium much more than most filmmakers. The end of “Inglorious Basterds” totally rips this off. Now I like that movie better.

• Really?! I didn’t make it very far into the film. It wasn’t that it was bad. But there are only certain moods when I can put up with Tarantino.

Re: Welles’ production. His idea was basically correct. But he should have taken it further. It’s great to put DQ in the modern world — that’s what’s going on in the first book. But he didn’t go the next step (and no one does) by moving to the second book where everyone knows who DQ is. But everyone is so damned worried about getting the windmills in there. And it’s remarkable that this is what everyone remembers from the book because it is an unremarkable bit — just the first time that Sancho sees that DQ is a raving lunatic — the first of many.

2. Football fans are the most atrocious racists around. When I moved to Minnesota, I followed the football Vikings for a while, precisely because they had African-Americans at quarterback and wide receiver. As one writer put it, I forget who, the default play was “throw it deep and I will catch it,” which was the play I loved in grade-school. Just pure body-smashing mayhem, with one guy reaching up and artfully cradling the ball. It was a delight to watch.

Well, Vikings fans did not like those players. They were too Negro-y. And I put up with this. For a few years.

They have these sports games on game consoles. And, over the years, those sports games have gotten highly realistic. The way people move, the physics of the sport, it’s all quite believable.

And the commentary. Recorded bits from noted sports commentators, cued by algorithms, to make the game feel like watching TV.

I’m addicted to these games. I love ’em. The basketball one has so many controller moves I can’t possibly figure it out, just like real basketball. The baseball one has the best interface ever. Press the button to swing. If it’s a ball, you’ll miss, if it’s a strike, you’ll hit it.

I’m playing an NFL game. And my running back breaks away, he’s headed for a sure touchdown. The commentators say, “he’s got speed! He’s got running-away-from-the-cops-speed!”

I shut the game off, sold it the next day, and never watched another NFL game again.

Football is the absolute worst.

• Wow. That’s amazing.

What do you think of Chris Rock’s take on why African Americans aren’t into baseball. As the only sport I really like, I don’t like it turning into a white man’s game.

• It’s ooky. You go to a ballpark now, and it’s heavy on the country-radio hits. That’s wrong.

Rock’s riff is genius. You’ll be happy to know that the Twins are banking on a Korean star whose bat flips are magnificent. You’ll be sad to know he already plans on not doing them anymore.

Is it April yet?

• You had mentioned that — maybe over on the Twin’s site. Apparently there is some MLB rule that things must be boring or something.

It’s interesting to look at professional sports in Japan where they all have their own songs. It isn’t exactly hip hop, but it’s interesting stuff. I highlighted one such composer on a birthday post long ago.

Maybe MLB is using the Republican theory that if they just get a larger and larger share of whites, they’ll be fine. Fine, that is, until it suddenly all fall apart.

• And the worst thing (bloviating here) is it’s not a honky game. It’s increasingly a Caribbean game. And baseball should be reaching out to Latino fans. They’re not. They’re going for old white conservatives. It’s small-minded and dumb. But that’s billionaire sports owners for ya. Not the brightest of bulbs.

• Yeah. Maybe the improving situation with Cuba will help. But I suspect the owners are more focused on how much they can sell those sky-boxes than they are the people in the stands.