FIP Calculated Incorrectly

Subliminal · 08-17-2020, 02:59 PM

It feels like the in game FIP calculations are incorrect. When we calculate FIP externally using the exported SQL data it never lines up with the in game numbers for any pitcher, ever (like it's not even close).

The formulas we are using to do the calculations for FIP and the FIP constant are as follows.

FIP = ((13*HR)+(3*(BB+HBP))-(2*K))/IP + constant

FIP Constant = lgERA – (((13*lgHR)+(3*(lgBB+lgHBP))-(2*lgK))/lgIP)

The numbers that come out from these formulas do not seem to be the same as the ones being used in game.

Is it possible to let us know the formulas being used in game so we can either change our code to match the in game formulas or can you change the in game formulas so they match the actual FIP formulas, if they are indeed incorrect?

Thanks again for your time, as always it's appreciated!

CBeisbol · 08-17-2020, 06:19 PM

Per the glossary

Quote:

FIP - "Fielding Independent Pitching" - developed by Tom Tango, a measure of all those things for which a pitcher is specifically responsible. The formula is (HR*13+(BB+HBP-IBB)*3-K*2)/IP, plus a league-specific factor (usually around 3.2) to round out the number to an equivalent ERA number. FIP helps you understand how well a pitcher pitched, regardless of how well his fielders fielded.

https://manuals.ootpdevelopments.com...&page=glossary

Seems like you would have mentioned it, but are your calculations always off by something that would suggest it was just a difference in the constant

Subliminal · 08-17-2020, 11:31 PM

That is my assumption, that OOTP calculates the constant differently than the formula I provided or uses a constant that doesn't use a formula, like somewhere around 3.2ish.

Matt Arnold · 08-18-2020, 09:46 AM

The only thing different I see is that you need to remove intentional walks when calculating the constant, and when you list your formulas at the top you're not factoring that part in.

How far different are your calculations?

Subliminal · 08-18-2020, 04:39 PM

I'll check that out and see if the results match a little later tonight. They're off by enough but IBB might potentially be the issue. It's definitely possible that it's me and not you, but I just wanted to confirm. I'll check tonight and get back to you with some comparisons if they don't match up after I take IBB out.

Subliminal · 08-18-2020, 05:15 PM

So upon more thought, IBB should already be factored into the BB stat so taking it out would just be redundant would it not?

Some FIP resources in which none of them show IBB being removed.
https://library.fangraphs.com/pitching/fip/
https://www.baseball-reference.com/b...ndent_Pitching
http://m.mlb.com/glossary/advanced-s...ndent-pitching

CBeisbol · 08-18-2020, 05:49 PM

Quote:

Originally Posted by Subliminal

So upon more thought, IBB should already be factored into the BB stat so taking it out would just be redundant would it not?

Some FIP resources in which none of them show IBB being removed.
https://library.fangraphs.com/pitching/fip/
https://www.baseball-reference.com/b...ndent_Pitching
http://m.mlb.com/glossary/advanced-s...ndent-pitching

IBB's are included in BB's

The reasoning behind taking them out is that they aren't reflective of the pitcher's skill, but the manager's decision

From the MLB.com definition

Quote:

Definition
FIP is similar to ERA, but it focuses solely on the events a pitcher has the most control over -- strikeouts, unintentional walks,

*emphasis mine

Subliminal · 08-18-2020, 06:15 PM

Ok so it looks like I can get my FIP calculation to match the in game calculation if I subtract IBB from BOTH formulas.

So this is what I had.
FIP = ((13*HR)+(3*(BB+HBP))-(2*K))/IP + constant
FIP Constant = lgERA – (((13*lgHR)+(3*(lgBB+lgHBP))-(2*lgK))/lgIP)

And this is what I changed it to.
FIP = ((13*HR)+(3*(BB+HBP-IBB))-(2*K))/IP + constant
FIP Constant = lgERA – (((13*lgHR)+(3*(lgBB+lgHBP-IBB))-(2*lgK))/lgIP)

That gives me the same FIP as shown in game. So that solves that problem then. Thanks for the help both of you, I appreciate it. I more or less wanted to know why my FIP wasn't coming out the same and it appears to be because OOTP uses a slight variation on the calculation from that of what is posted on MLB. Thanks again!

08-17-2020, 02:59 PM	#1
Subliminal Minors (Single A) Join Date: May 2004 Posts: 74	FIP Calculated Incorrectly It feels like the in game FIP calculations are incorrect. When we calculate FIP externally using the exported SQL data it never lines up with the in game numbers for any pitcher, ever (like it's not even close). The formulas we are using to do the calculations for FIP and the FIP constant are as follows. FIP = ((13HR)+(3(BB+HBP))-(2K))/IP + constant FIP Constant = lgERA – (((13lgHR)+(3(lgBB+lgHBP))-(2lgK))/lgIP) The numbers that come out from these formulas do not seem to be the same as the ones being used in game. Is it possible to let us know the formulas being used in game so we can either change our code to match the in game formulas or can you change the in game formulas so they match the actual FIP formulas, if they are indeed incorrect? Thanks again for your time, as always it's appreciated! Last edited by Subliminal; 08-17-2020 at 03:01 PM.

08-18-2020, 05:15 PM	#6
Subliminal Minors (Single A) Join Date: May 2004 Posts: 74	So upon more thought, IBB should already be factored into the BB stat so taking it out would just be redundant would it not? Some FIP resources in which none of them show IBB being removed. https://library.fangraphs.com/pitching/fip/ https://www.baseball-reference.com/b...ndent_Pitching http://m.mlb.com/glossary/advanced-s...ndent-pitching Last edited by Subliminal; 08-18-2020 at 05:19 PM.

08-17-2020, 11:31 PM	#3
Subliminal Minors (Single A) Join Date: May 2004 Posts: 74	That is my assumption, that OOTP calculates the constant differently than the formula I provided or uses a constant that doesn't use a formula, like somewhere around 3.2ish.

08-18-2020, 09:46 AM	#4
Matt Arnold OOTP Developer Join Date: Jun 2009 Location: Here and there Posts: 16,244	The only thing different I see is that you need to remove intentional walks when calculating the constant, and when you list your formulas at the top you're not factoring that part in. How far different are your calculations?

08-18-2020, 04:39 PM	#5
Subliminal Minors (Single A) Join Date: May 2004 Posts: 74	I'll check that out and see if the results match a little later tonight. They're off by enough but IBB might potentially be the issue. It's definitely possible that it's me and not you, but I just wanted to confirm. I'll check tonight and get back to you with some comparisons if they don't match up after I take IBB out.

08-18-2020, 06:15 PM	#8
Subliminal Minors (Single A) Join Date: May 2004 Posts: 74	Ok so it looks like I can get my FIP calculation to match the in game calculation if I subtract IBB from BOTH formulas. So this is what I had. FIP = ((13HR)+(3(BB+HBP))-(2K))/IP + constant FIP Constant = lgERA – (((13lgHR)+(3(lgBB+lgHBP))-(2lgK))/lgIP) And this is what I changed it to. FIP = ((13HR)+(3(BB+HBP-IBB))-(2K))/IP + constant FIP Constant = lgERA – (((13lgHR)+(3(lgBB+lgHBP-IBB))-(2lgK))/lgIP) That gives me the same FIP as shown in game. So that solves that problem then. Thanks for the help both of you, I appreciate it. I more or less wanted to know why my FIP wasn't coming out the same and it appears to be because OOTP uses a slight variation on the calculation from that of what is posted on MLB. Thanks again!