Sabermetrics School and Analysis

[whitesoxfan83]

Creating a sticky thread of all the formulas for different stats would be pretty sweet (Even real basic stuff like OBP and SLG). It could be something that would be locked and stickied, where whoever creates it could just post the different formulas and people could use it as a reference.

I really understand this stuff a lot better when i see the formulas laid out, i have a feeling im not the only one.

[k_rock923]

What do you mean? Groundballs provide the smallest run expectancy for balls in play (with the exception of infield pop-ups of course), so it wouldn't be a terrible thing. It depends on your definition of "a ton" and "lots". Give me a pitcher for example.

I'm a little confused on that, actually. In the explanation, FIP was derived from strikeouts, walks, hit batters, and homeruns. If you have a pitcher that predominately gives up ground balls, does he get shortchanged?

I guess it depends on whether a ground ball pitcher is really that much better than a fly ball pitcher. The conventional wisdom says that he is, but are they really more effective? If so, it would seem that FIP doesn't give them credit for that effectiveness. If not, I suppose it's a moot point.

Reading the post further, are these just natural criticisms of FIP that tRA address?

[iam brett favre]

Whats a sabermetric?

[Gigantes4Life]

Creating a sticky thread of all the formulas for different stats would be pretty sweet (Even real basic stuff like OBP and SLG). It could be something that would be locked and stickied, where whoever creates it could just post the different formulas and people could use it as a reference.

I really understand this stuff a lot better when i see the formulas laid out, i have a feeling im not the only one.

That shall be done, I'll maybe post them in the glossaries thread and then someone can edit them into the OP.

I'm a little confused on that, actually. In the explanation, FIP was derived from strikeouts, walks, hit batters, and homeruns. If you have a pitcher that predominately gives up ground balls, does he get shortchanged?

I guess it depends on whether a ground ball pitcher is really that much better than a fly ball pitcher. The conventional wisdom says that he is, but are they really more effective? If so, it would seem that FIP doesn't give them credit for that effectiveness. If not, I suppose it's a moot point.

Reading the post further, are these just natural criticisms of FIP that tRA address?

Yes that was my mistake, I was thinking in terms of tRA. Yes, FIP is weak because it doesn't account for those things, and you're exactly correct - tRA takes it one step further.

[iam brett favre]

Seriously though, what is tRA? I use it, but honestly I dont know what it means.

[Gigantes4Life]

We don't really have a widely available coherent metric for pitchers which tells us how good a pitcher is, independent of his home park and the defence behind (and if anyone feels tempted to say 'ERA' here, read Dave Cameron's article on pitcher evaluation first). FIP and xFIP are the most commonly used general pitching stats we have, but they suffer from the limitation of only considering strikeouts, walks, hit batsmen and home runs. We know there are other things that are mostly under a pitcher's control, and we also know roughly how much control a pitcher asserts over said events. The hope for tRA then was to construct a metric which takes into account every action a pitcher is responsible for and turns those numbers into runs and outs based around a highly logical and transparent mathematical framework.

That's the introduction from StatCorner.

The idea is that it measures all events in which the only thing going into the calculation happen from when the pitcher throws the ball, to which the batter either swings or doesn't swing.

Everything that happens from then on is completely out of the pitcher's control (excluding his defense).

[k_rock923]

How was the relative amount of control a pitcher has over an event determined?

Since I keep asking questions about pitching stats, are there any web pages I should look at for information?

[Gigantes4Life]

Sure. Read this: http://statcorner.com/tRAabout.html

As for your question about amount of control, what do you mean?

A pitcher can control the pitch he throws, and he has influence on whether it's a strike, ball, groundball, line drive, flyball, etc. After that, who knows what happens. Pop ups fall, line drives get caught, flyballs go out in certain ballparks. Over time, all these events have a certain run value.

[Gigantes4Life]

Also, I think we might be leaving simple questions behind

[k_rock923]

Sure. Read this: http://statcorner.com/tRAabout.html

As for your question about amount of control, what do you mean?

A pitcher can control the pitch he throws, and he has influence on whether it's a strike, ball, groundball, line drive, flyball, etc. After that, who knows what happens. Pop ups fall, line drives get caught, flyballs go out in certain ballparks. Over time, all these events have a certain run value.

Thanks for the link. I was referring to this line in the explanation:

We know there are other things that are mostly under a pitcher's control, and we also know roughly how much control a pitcher asserts over said events.

How do we know how much control a pitcher has over certain events. I gather from the explanation, that these other factors are essentially things that the pitcher does, without the influence of the defense aside from the following: strikeouts, walks, hit batsmen and home runs.

edit: Yea, sorry. I'm getting a little off track of the topic here. Maybe a mod should snip these posts that veered off of simple questions into another thread.

[Gigantes4Life]

Thanks for the link. I was referring to this line in the explanation:



How do we know how much control a pitcher has over certain events. I gather from the explanation, that these other factors are essentially things that the pitcher does, without the influence of the defense aside from the following: strikeouts, walks, hit batsmen and home runs.

edit: Yea, sorry. I'm getting a little off track of the topic here. Maybe a mod should snip these posts that veered off of simple questions into another thread.

I'm not entirely sure I get what you're asking, but this is what it sounds like. You want to know how much control a pitcher has on those events, like groundball, flyball, etc.? Like an actual value or what?

[k_rock923]

I'm not entirely sure I get what you're asking, but this is what it sounds like. You want to know how much control a pitcher has on those events, like groundball, flyball, etc.? Like an actual value or what?

Yea, that's about it. It sounds as if they're assigning some type of quantifiable value as to 'how much' control a pitcher has over an outcome. So, 'a pitcher controls n percent of all of the variables that determine whether a given pitch is a ground ball or fly ball etc.'

Now, it's entirely possible that I'm reading into it too much and I'm hung up on the wording of that introduction. If so, what is that line actually saying? Thanks.

[Gigantes4Life]

I can't say for sure, but based on the next paragraph I believe that when they say mostly, that it depends on the type of batter the pitcher is facing. So over time, we can assume that the events are predominantly in the pitcher's control, and there's no reason to read that much farther into it.

The other thing that they may be considering is if the ballpark affects how the pitcher throws, but for the sake of simplicity they simply let it go.

[k_rock923]

Okay, thanks. I think that I'm misinterpreting what the text is trying to say. I'll stop hijacking the 'simple questions' thread with small details now

[C1Bman88]

Actually, I'll expand. Fangraphs uses a different wOBA formula than Statcorner. Which one is the better one in people's opinions? And why? Perhaps this isn't a simple question and warrants it's own thread.

Fangraphs' is better, IMO. Statcorner doesn't include SB and CS, but incorporates ROE. And I honestly don't know if they use the correct RV scale, because it changes from year to year. I know Fangraphs does.