Predictive game scores: Opening Week

It is one thing to grab a sample of past games and see how a predictive formula does. It's a wholly different experience to put that predictive method against real games before they happen.

A couple months ago, I started working on a method to predict a game's outcome by running the statistics of the pitcher against that specific opposing lineup. It culminated in a three-part series published right here at Beyond the Box Score. You can read the conclusion here but, in short, it didn't work out the way I had hoped. That being said, it represented a step in the right direction for predictive analysis. At least for one person's research purposes.

Without much more delay we will get to the way the formula expected Opening Day to play out. But first, this is a very laborious exercise of data gathering and in a very compressed amount of time, because lineups are posted fairly late. I point this out to show you that a) this formula isn't very practical for actually predicting a game, and b) a better iteration could be used as more of a macro prediction (to predict a pitcher against a certain division's worth of players, for instance). In fact, it was so difficult to gather lineup data before the game happened that I didn't get it done in time. That is why this article will predict today's games instead. However, since I have the data collected anyway, let's take a look at how the formula expected Opening Day to play out.

Pitcher	pBJGS	Actual
Jon Lester	62	39
Adam Wainwright	78	68
Masahiro Tanaka	75	38
Drew Hutchison	27	63
David Price	80	79
Phil Hughes	50	45
Kyle Lohse	33	9
Kyle Kendrick	33	69
Cole Hamels	63	44
Clay Buchholz	61	79
Chris Archer	90	47
Chris Tillman	66	63
Max Scherzer	76	71
Bartolo Colon	66	69
Henderson Alvarez	66	59
Julio Teheran	78	55
Yordano Ventura	60	61
Jeff Samardzija	78	38
Felix Hernandez	83	78
Jered Weaver	66	41
Johnny Cueto	75	78
Francisco Liriano	69	69
Clayton Kershaw	109	55
James Shields	58	58
Dallas Keuchel	62	72
Corey Kluber	80	69
Sonny Gray	84	82
Yovani Gallardo	70	38
Josh Collmenter	65	27
Madison Bumgarner	90	63

Some stray observations before we get to tonight's predictions. First, the formula actually got one right! And it actually got two right! Francisco Liriano and James Shields' performances were spot-on the projections. Second, the formula clearly loves Kershaw way too much. This is likely a product of it depending on pitching trends. There's an implicit assumption in the formula that says 'hot' pitchers will stay 'hot' and 'cold' pitchers will stay 'cold.' It isn't weighted that much, but in Kershaw's case, it doesn't have to be on account of his machine-like performance last season.

It also likes Chris Archer way too much. That one is weird to me, but it probably has a lot to do with his splits. He faced 6 right-handers yesterday and has a career 0.263 wOBA against right-handed hitters. In other words, it might not be the best idea long-term to continue putting a lot of right-handed hitters in against Archer. The opposite can be said about Drew Hutchison. He faced 8 left-handed batters in yesterday's Yankees lineup and has a career 0.353 wOBA against left-handed hitters. I digress, it will be wrong often.

Without further delay, ladies and gentlemen, place your bets.*

* - please don't use this to gamble unless you plan on losing your college fund.

Pitcher	pBJGS
Mat Latos	86
Alex Wood	78
Nate Karns	20
Wei-Yin Chen	58
Matt Garza	53
Jordan Lyles	37
Rubby De La Rosa	30
Ryan Vogelsong	61
Jesse Hahn	79
Colby Lewis	42
James Paxton	83
C.J. Wilson	57
Zack Greinke	82
Tyson Ross	64

. . .

All statistics courtesy of FanGraphs.

Michael Bradburn is a Featured Writer for Beyond the Box Score. You can follow him on Twitter at @mwbii. You can also reach him at michaelwbii@gmail.com