Rethinking Park Factors

Fangraphs does an excellent job of tracking park factors for each MLB Stadium, but I’ve always wondered why it seems to over-rate the Rays bats while under-valuing their pitching. Everyone knows intuitively that each park plays differently when it comes to scoring runs, but a bit more nuance shows that each park favors various outcomes differently, as well. Currently, wRC+ appears to use the “basic” PF for adjusting wOBA for park, but this may not be the best approach. Come along for the ride as I attempt to find a better way to adjust for park effects.

First things first, what are the basic inputs for wOBA? We know that scoring runs is dependent upon getting on base and hitting for power. While OBP and SLG do a good job of representing each of these aspects they have flaws due to having different denominators (which is why you should almost never use OPS), but also due to their own inputs. OBP considers a walk and a home run to be of equal value while SLG considers a home run to be worth four times as much as a single, while not even including walks. The beauty of wOBA is that it combines both of these things and uses linear weights to derive the actual run expectancy of each outcome. You can scale these things to league offense, but I prefer to use the static coefficients that you find in the link above:

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Series Preview: Rays at Orioles April 14 – 16

Now that the matchup tool has been park adjusted I wanted to take a stab at previewing the next Rays series that starts tonight at 7 PM at the Baltimore Orioles. Game one features Wei-Yin Chen taking on our own Chris Archer:

Longo should be the class of this game, but Crush Davis is right there with him and then we see a couple of more Rays slated for success. Nick Markakis might be a guy that’s easy to sleep on, but he matches up very well with the Chris Archer that has shown a significant platoon split in his short career. This also bodes well for Clevenger as he might see a start with Wieters already seeing so much time behind the dish. Archer’s splits will help him against two very dangerous hitters in Cruz and Jones, but this is a fairly balanced lineup.

Game two pits Jake (H)odorizzi against the righty Miguel Gonzalez.

The cream shows a pretty even split between our good hitters and theirs, but in the middle we see the O’s having a bit of an advantage. Hodor doesn’t have much of a baseline, still, and the projections don’t know about his Thing with only two starts factored in for this year, but Gonzalez has a longer track record with ok to good results.

The final game pairs the best from each team as our own David Price seeks to extend his success against Chris Tillman.

We should match up pretty well with the righty and Price should only have a couple of landmines to work around in Cruz and Wieters. The Rays need to continue to take two of three, especially intra-division, and they seem well-poised to do so here. The Rays have been abysmal against lefties to start the year, but getting off on the good foot tonight should set them up well to take this series. I don’t have time for a full write up, but here’s our offensive performance through April 11:

WordPress has decided to make it so that you can’t resize images so you’ll probably want to open that in a new tab. Yuck city versus lefties and we haven’t exactly gone out and achieved against righties, either.

Lastly, I wanted to show the bullpen matchups:

The top table shows the matchup projections for each of our guys versus each of theirs and the bottom adjusts for if our hitter is is coming up in a pinch. I think this could be handy for trying to isolate who should be facing whom in those high-leverage late innings. Here’s how the Rays match up:

I have not included Brad Boxberger who should be available for this series so make fun of me if you wish. Be careful with Chris Davis and don’t let the other one to two scary guys beat you on a given day and the Rays should bode well. It sure would be nice to see the offense get going, but at the very least we could use some deep starts from each of our guys.

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First Time Through the Rotation

No predictive value here, but I think it would be fun to take an early look at what our pitchers did the first time through the rotation. I’m using he Pitch F/x data from Brooks Baseball with some of my own calculations. Those that are familiar with the site will recognize the format here so I won’t spend a ton of time explaining. Let’s start by looking at what they threw and how effective it was to lefties, righties and both:


In the top left we have the number of each type of pitches thrown to both types of batters and the total. Fastballs include two-seamers, four-seamers, sinkers, cutter, and this time only I’m including splitters in with fastballs instead of the second type of pitch, change ups. The third type are breaking balls composed of curves, sliders, and knuckle curves. I do not include intentional balls nor pitchouts.

In the bottom left the raw number of pitches is expressed as a percentage. Note that the total columns show the platoon split faced. As an example, Alex Cobb faced 51% lefties while Moore only threw 9% of his pitches to lefties. You can see how each of our pitchers approached a batter. For instance, among starters, Alex Cobb threw the most breaking balls to lefties while Matt Moore didn’t throw a single one. In fact, Moore only threw fastballs to lefties. Cobb and Odorizzi were the only starters to throw change ups to lefties, with Odo throwing his new pitch almost a third of the time. Look through and find your own interesting things, but how about Cobb only throwing 42% of his pitches as fastballs. Odo was in a similar boat, but the other end of the spectrum shows Price, Archer and Moore throwing over 70% fastballs.

Moving to the top right we find the total number of runs either earned or given away for each pitch to each type of batter. Starting on the right with the totals we can see the relatively poor performance from Cobb and Moore. Cobb struggled mightily with lefties and uncharacteristically we can see that his very good change was a big reason why, though the breaking ball wasn’t doing him any favors. The curve was strong to righties, but they had success on the fastball. For Moore, his problem related to all those righties and the face that his curve was garbage and his fastball wasn’t a whole lot better. Odorizzi garnered the most runs saved based off the back of his change to lefties and fastball to righties.

In the bottom right we have the total runs adjusted per 100 pitches to attempt to put all these things on an even keel. It breaks down when only a handful of pitches have been thrown, but this is less of an issue over an entire season so we’ll spend more time with that later in the year. For now, let’s move over to a couple of other things I like to quantify:


You may want to refer to the earlier chart for the raw number of pitches thrown in each scenario, but for this chart we’ll focus on the pitches thrown in the called zone, on the left, and the pitches that were swung upon, on the right. It’s impressive that Archer and Odorizzi were able to throw their breaking balls in the zone to lefties more than 60% of the time and Cobb threw his change up in the zone almost 80 of the time. Overall, Odo threw nearly 60% of his pitches to lefties in the strike zone while he’s chased by Cobb (53%), Archer/Cobb (45%) and Moore (40%). Against righties we see a different story with Price leading the way at 63% strikes and followed by Archer (54%) then Odo (54%), Moore (48%) and weirdly Cobb at 42%.

Lastly we can flip over to the % of pitches that drew swings. Overall, we can see that Cobb only had 37% of his pitches get swung upon while Odo did him one better at only 36%. The other side sees Price leading the way with 49%, nearly half of his pitches, were swung at with Archer at 43% and Moore at 40%. There’s a lot to glean here so I’ll leave it to the reader to tell a tale or two, but I wanted to share this to give an indication of what we saw on the field. I hope to continue to bring this as much as I can as it should make a nice comparison start to start.

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Chris Archer Wages War On Parallel Universe Chris Archer

Some believe in the idea that there are infinite parallel universes out there in the yonder. Carbon copies doing different things, living different lives, in similar worlds. We’re familiar with the concept via 1970′s science-fiction writing, but today I wanted to focus on just two of these universes. In Universe A we have calm, cool, mild-mannered Chris Archer. He is focused, he is unemotional, he carries the swagger of a killbot designed for one purpose, to kill batters without once taking pleasure in his mission.

In Universe B we have wildman Chris Archer. He starts bar fights and gets fired up when the Jets turn the ball over. This Chris Archer is the emotional one that is prone to snap before begging your forgiveness. He’s polite, but that doesn’t stop him from enjoying a cigar after taking your mama out for a spin. This Chris Archer is liable to do anything, as he once sang along, probably, “As long as I got my beretta, I’m down for whateva.”

These Chris Archers will never meet. They will never know each other exists. They will go on to have wildly divergent career paths due to mental maturity, physical luck, and those Gottdang dinosaurs that we thought were extinct, but in one of these universes they are brought back into existence by a totes mean necromancer named Jabari Parker (parallel universes, brah).

Yesterday, I mocked up what some different scenarios would look like for Chris Archer… Continue reading

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Chris Archer Decides to Stick Around for Awhile

It looks like Rays righty Chris Archer might want to buy a nicer house in St. Jetersburg now that he can afford it. It would appear that the two sides have reached an agreement to a six year contract with two option years. I probably don’t have to tell you that this has the potential to be an incredible deal, but I did want to show some stuff that shows that this has the chance to be an incredible deal:

If Chris Archer is fairly average over the next few years and then has a traditional fall off starting his last year of team control then you’re talking around 13 wins at a cost of $42.5M and on-field production of around $84M. So if Chris Archer is mediocre we’re looking at something like double the value and in all likelihood those options at the end aren’t picked up so you can probably knock another 16-18M off that figure and just cut bait on the last two years. What if Archer becomes a star?:

Let’s say he has a slow build over the next few years culminating in a peak of 4.5 WAR with traditional slopes on either side of that summit. We’d still be paying him that roughly $42.5M, but now he’s producing 28 wins over the eight years and providing something like $186M in on-field value for a crazy-good surplus of almost $145M. And if he’s somewhere in between he’s still a really good value.

With any of these signings you’re betting that the player isn’t going to have a catastrophic, career-ending injury, but that does happen from time to time. As such, there needs to be some risk factored in that I’m not including and you may also want to downgrade future wins a nudge, because they’re far away and not soon. On the other hand, this is a fairly conservative inflation rate of 5% so keep in mind this is just a model and not perfection.

Whether you believe Sir Plus is better met by comparing future or present value to production is up to you, but I have used present value here. Apply whatever caveats you wish and this appears to be another feather in the cap for the Rays front office. Kudos on getting a smart, hard working, ridiculously talented player to sign on the line so that us fans can get a jersey we know will be here for awhile, and kudos to Chris Archer for realizing that a lot of money is a lot of money. It might be less than more money, but it’s here today and sticking around for awhile. Get cozy, kid.

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To Review or Not to Review, That is the Question

Ok so those that watched the game saw a play early in the game that may have been a good idea to challenge.

Of course, I’m talking about Colby Rasmus’s lead-off walk in the third. It sure looked like David Price picked him off, but the play was close so even with replay we’re probably talking like a 50-50 that it could go either way. What do the numbers show? Well a runner on first and no outs leads to around .95 runs on average while if the out is called then you’re staring at nobody on and one out, a situation that averages around .30 runs.

Right off the bat you see that you’re talking about this play being worth around .65 runs, but we also need to factor in leverage since it was already 3-0 and it was early. The leverage of the situation was .81 so we can multiply that by the run expectancy to adjust for the situation. This yields .53 context runs for the situation. If Maddon thinks that another play will be close, reviewable and worth more than .53 context runs between the third and the end of the sixth then absolutely sit on the challenge, but I don’t think anything else would be worth much more than that while still being reviewable.

So here’s the problem, manager’s don’t see that baserunner as a big deal, but you’re talking something like half a run which is a huuuge deal in a single game. Plays like that might seem small in the big picture, but these are exactly what you should be challenging because with the unlikelihood of a more important play being missed later there’s no reason to keep the review in your pocket.

Instead we are treated to a dog and pony show on the field where are young heart throb Sam and Diane’s the umpire until he gets a thumb’s up which breaks up the game, slows it down, and ultimately will rarely lead to a review. Instead of dicking around out there once you break the chalk that should signify that you’re requesting a review. If you think it’s close then review it. If you’re right you get another and if you’re not it’s not like you’re the District Attorney aiming for a 100% conviction rate. Throw it out there and see what happens, but holding on to it for a rainy day is going to leave a lot of runs on the field.

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