We're nearing the halfway point of the baseball season, with the All-Star break right around the corner. It's a slower Monday with only three bets showing value, but let's get the week off to a good start.
The Model
The process is relatively simple. First, I start by assuming that the full game (implied) run totals for either team are roughly efficient. As mentioned above, that tends to be the case more often than not. This saves me the trouble of trying to predict the total runs scored in the game — and allows me to focus strictly on the "when" rather than "how many."
Next, I built a database of pitchers' performances the first time through the order, relative to their overall stats. Since the latter is presumably baked into the full game total, I wanted to figure out if those runs are more likely to come early or late. Most — but not all — MLB starters do somewhat better early in games, but with some variance in just how much. The model uses xFIP (expected Fielding Independent Pitching) as the ERA predictor of choice.
That's only half of the equation, though, with the offenses making up the other half. To do this, I looked at what percentage of a team's total runs is produced by the top three batters in the lineup. While a first-inning run scored, by definition, needs at least four hitters to come to the plate, one of the first three has to actually score it. The metric of choice here is wRC+, based on the projected lineup for the day from each team.
This is a bit of a tradeoff, as lineups (and run totals) can shift throughout the day, especially if significant contributors miss time. However, in my experience, the inefficiency of the morning lines more than makes up for the leakage in the model. With that said, exercise caution if, say, Mike Trout is listed as questionable for the night's game.
The Picks
With all of the picks below, I'll include the pick, the best line and the threshold I'd bet it to. These will go up in the morning, so if any major news breaks between publishing and when you read it, be sure to consider that.
Infrequently, rather than betting on the traditional YRFI/NRFI, the pick will be on one team or the other specifically to score a run, which as of this writing is only a betting option at DraftKings. Since the model handles each team individually, sometimes one team is projecting for a greater proportion of the "run equity" in the first inning than the betting lines are accounting for.
NRFI Odds, Picks for Monday, June 19
Washington Nationals vs. St. Louis Cardinals YRFI: My gut reaction was that this would be a good time for a team-specific pick on the Cardinals. However, Washington is projecting better than you might think, thanks to Jack Flaherty having mediocre splits his first time through the order.
Pick: Nationals-Cardinals YRFI |
Houston Astros vs. New York Mets NRFI: Two stud pitchers with excellent splits the first time through the order square off here. If you don't have access to any of the books with the better line (BetRivers or other Kambi books), I'd consider using the -140 line at DraftKings as part of a parlay with another "safe" leg.
Milwaukee Brewers vs. Arizona Diamondbacks YRFI: This one is a bit of an anomaly. Most of the projection is due to Corbin Burnes having very poor splits his first time through the order — when basing it on xFIP. His ERA is actually better his first time around the lineup than his overall number, which is more typical of starting pitchers.
It seems weird to think that Burnes has been very lucky his first time through the order and then unlucky the rest of the time, but that's been the case through his 80-plus innings so far this season.
With xFIP being a far better predictor of future ERA than past ERA, we're going with this one at plus money — though I wouldn't fault anyone for passing or making this a half-unit bet.
Pick: Brewers-Diamondbacks YRFI |
