Daily MLB Tip: Utilize the Vegas Lines

Jonathan Bales is the author of Fantasy Baseball for Smart People—a guide designed to help you profit on DraftKings.

The best companies in the world do a really nice job of outsourcing tasks that increase the overall efficiency of the company while aiding in improving their bottom line. If we’re thinking of ourselves as the CEOs of daily fantasy baseball prediction companies, then it makes sense that we should spend as little time as possible on things that we can have others do for us, assuming they can do it at the same level or better.

Wouldn’t it be amazing if there was some sort of entity out there that had all kinds of money riding on the outcomes of sports games and individual player performances and was thus incentivized to make really accurate predictions that we could basically just steal?

Oh, there is? Yeah, there is: Vegas. Vegas accounts for basically every relevant factor when they set their spreads, totals, and props. They’ve proven to be extremely accurate in the past. While Vegas cares about public opinion, their first aim is to create an accurate line. If they do that, they’ll limit their downside and maximize long-term profits.

The Accuracy of Vegas

For us daily fantasy baseball players, it really comes down to one question: can the Vegas lines help us make more accurate predictions? And that answer, without a doubt, is yes. We have the best oddsmakers in the world weighing weather, ballpark factors, pitcher matchups, recent performance, and lots of other factors. When they predict that the Cowboys will score 24 points or that the Rangers’ median projection is five runs, that’s highly likely to be very close to reality. There’s all sorts of data that I’ve collected in various sports showing how accurate Vegas has been.

Even if you consider what Vegas offers to be “common sense”—an argument I’ve heard from a number of people who somehow have decided to forgo leveraging their apparent ability to beat Vegas into huge profits—there’s no doubt that we can increase our efficiency by stealing Vegas’s predictions.

I liken this to a company outsourcing work that they can get completed cheaply and more efficiently than what they could do on their own. So why in the world would you run through all of the work of considering 100 different inputs that might affect a baseball team’s run projection when you can get that information immediately from a highly reliable source? Even if you were just as accurate—and you likely aren’t—it still wouldn’t make sense to not take that sort of data for free. The cost—a couple minutes of your time—is basically nothing, yet you can receive all sorts of incredibly useful insights.

At this point, I think it’s important to confirm that Vegas is not only accurate, but also a reliable tool for daily fantasy players. So I looked at the overall fantasy production for teams in games projected at eight runs, then compared that to other run totals.

There’s a very clear, linear relationship here; games projected at six runs by Vegas have historically seen between 20 and 30 percent fewer fantasy points than those projected at eight runs—depending on if we use the opening or closing line. On the other end of the spectrum, games projected at 10.5 runs have witnessed around 33 percent more fantasy points than those projected at eight runs. Those are pretty sizeable differences, eh?

I also charted the reliability of using the Vegas lines as a direct proxy for fantasy scoring. Here’s a look at how the change in run total has historically compared to the change in fantasy production.

Up until the 9.5-run mark, fantasy production has been directly linked to the Vegas lines—an almost perfectly linear correlation. What’s really interesting is that actual fantasy production jumps considerably over what we’d expect once hitting the projected 10-run mark, i.e. if you targeted teams in games projected at 10 or more runs, you would have seen a sizeable jump in fantasy production over games at just 0.5 fewer projected runs.

I’m not entirely sure why this is the case. It could just be that teams with really high projected run totals also have far more upside than others. Maybe 10.5 runs is the median projection for a specific game, but the high-upside offenses in that sort of contest have the ability to occasionally erupt for 20-run sorts of contests that throw off the overall numbers. Or perhaps we’re looking at Vegas’s ceiling on how high they’ll go with projected run totals.

Either way, two things are true:

1) We can trust the Vegas lines to help project players in daily fantasy baseball. 2) When possible, we should target hitters in games with a high projected total.

Leveraging the Lines

There are three useful numbers that Vegas can give us in baseball: the total, the moneyline, and props. The total is the projected number of runs for both teams combined. The moneyline offers odds of each team winning. Props are individual predictions of a particular player or team’s performance. There are generally moneylines associated with the totals and props in MLB which change the odds, and you can use the total and moneyline to calculate a team’s projected run total.

Those projected run totals are really useful in daily fantasy baseball, particularly if you plan to stack an entire offense. If you want to use six batters on the White Sox, for example, the Vegas line will be really important in deciphering your lineup’s upside. If Vegas has Chicago projected at 5.2 runs and you’re using two-thirds of their offense, that total is going to be strongly linked to your fantasy production.

I also use the projected run totals to target pitchers. Baseball is obviously zero-sum such that the success of a pitcher is directly related to the lack of success for an offense; when Vegas has a particular team projected really poorly, it’s a good sign that the opposing pitcher will perform well. The moneyline is important, too; when a particular team is a big favorite to win, the starting pitcher for that squad also has a high probability of getting fantasy points for a win.

The overarching idea here is that Vegas can and should be a very fundamental part of your daily fantasy baseball research process. In an extremely short amount of time, you can identify which teams are likely to win, how much they’re likely to win by, and (with player props) which players are the best bets for elite fantasy production.