Archive for Library News

FanGraphs Library Stat Glossary

To find a particular statistic, use Ctr-F and type in the abbreviation or stat name that you are looking for.

Offense:

OBP – On-Base Percentage
OPS – On-base Plus Slugging
OPS+ - On-base Plus Slugging Plus
wOBA – Weighted On-Base Average
wRAA – Weighted Runs Above Average
UBR – Ultimate Base Running
wRC – Weighted Runs Created
wRC+ – Weighted Runs Created Plus
BABIP – Batting Average on Ball In Play
ISO – Isolated Power
HR/FB – Home Runs per Fly Ball rate
Spd – Speed Score
GB% – Ground ball percentage
FB% – Fly ball percentage
LD% – Line drive percentate
K% – Stikeout rate
BB% – Walk rate
O-Swing% - Outside-the-zone swing rate
Z-Swing% - Inside-the-zone swing rate
Swing% - Swing rate
O-Contact% - Outside-the-zone contact percentage
Z-Contact% - Inside-the-zone contact percentage
Contact% - Contact percentage
Zone% - Percentage of pitches within the zone
F-Strike% - First-pitch strike percentage
SwStr% – Swinging Stike percentage
wFB - Fastball runs above average
wSL - Slider runs above average
wCT - Cutter runs above average
wCB - Curveball runs above average
wCH - Change-up runs above average
wSF - Split-finger fastball runs above average
wKN - Knuckleball runs above average
wFB/C - Fastball runs above average per 100 pitches
wSL/C- Slider runs above average per 100 pitches
wCT/C - Cutter runs above average per 100 pitches
wCB/C - Curveball runs above average per 100 pitches
wCH/C - Change-up runs above average per 100 pitches
wSF/C - Slit-fingered fastball runs above average per 100 pitches
wKN/C - Knuckleball runs above average per 100 pitches

Defense:

rSB - Stolen Base Runs Saved runs above average
rGDP - Double Play Runs Saved runs above average
rARM - Outfield Arms Runs Saved runs above average
rGFP - Good Fielding Plays Runs Saved runs above average
rPM - Plus/Minus Runs Saved runs above average
DRS - Defensive Runs Saved runs above average
BIZ - Balls In Zone
OOZ - Balls Out Of Zone
RZR - Revised Zone Rating
CPP - Expected Catcher Passed Pitches
RPP - Catcher Blocked Pitches in runs above average
TZ - Total Zone
TZL - Total Zone with Location data
FSR – Fan Scouting Report
ARM - Outfield Arm runs above average
DPR - Double Play runs above average
RngR - Range runs above average
ErrR - Error runs above average
UZR - Ultimate Zone Rating
UZR/150 - Ultimate Zone Rating per 150 defensive games

Pitching:

ERA – Earned Run Average
WHIP – Walks and Hits per Innings Pitched
FIP – Fielding Independent Pitching
xFIP – Expected Fielding Independent Pitching
SIERA – Skill-Interactive ERA
tERA – True Runs Allowed
K/9 – Strikeout rate
BB/9 – Walk rate
K% – Strikeout percentage
BB% – Walk percentage
K/BB – Strikeout-to-Walk ratio
LD% - Line drive rate
GB% - Ground ball rate
FB% - Fly ball rate
HR/FB – Home runs per fly ball rate
BABIP – Batting Average on Balls In Play
LOB% – Left On Base percentage
ERA- - ERA Minus
FIP- FIP Minus
xFIP- - xFIP Minus
SD – Shutdowns
MD – Meltdowns
O-Swing% - Outside-the-zone swing rate
Z-Swing% - Inside-the-zone swing rate
Swing% - Swing rate
O-Contact% - Outside-the-zone contact percentage
Z-Contact% - Inside-the-zone contact percentage
Contact% - Contact percentage
Zone% - Percentage of pitches within the zone
F-Strike% - First-pitch strike percentage
SwStr% - Swinging Stike percentage
wFB - Fastball runs above average
wSL - Slider runs above average
wCT - Cutter runs above average
wCB - Curveball runs above average
wCH - Change-up runs above average
wSF - Split-finger fastball runs above average
wKN - Knuckleball runs above average
wFB/C - Fastball runs above average per 100 pitches
wSL/C- Slider runs above average per 100 pitches
wCT/C - Cutter runs above average per 100 pitches
wCB/C - Curveball runs above average per 100 pitches
wCH/C - Change-up runs above average per 100 pitches
wSF/C - Slit-fingered fastball runs above average per 100 pitches
wKN/C - Knuckleball runs above average per 100 pitches

Win Probability:

WPA - Win Probability Added
-WPA - Loss Advancement
+WPA - Win Advancement
RE24 - Run Above Average based on the 24 Base/Out States
REW - Wins Above Average based on the 24 Base/Out States
pLI - A player’s average LI for all game events
phLI - A batter’s average LI in only pinch hit events
PH – Pinch Hit Opportunities
gmLI - A pitcher’s average LI when he enters the game
inLI - A pitcher’s average LI at the start of each inning
exLI - A pitcher’s average LI when exiting the game
WPA/LI – Situational Wins
Clutch - How much better or worse a player does in high leverage situations than he would have done in a context neutral environment

WAR

Offensive

Batting - Park Adjusted Runs Above Average based on wOBA
Base Running -  Base running runs above average, includes SB or CS
Fielding - Fielding Runs Above Average based on UZR (TZ before 2002)
Replacement - Replacement Runs set at 20 runs per 600 plate apperances
Positional - Positional Adjustment set at +12.5 for C, +7.5 for SS, +2.5 for 2B/3B/CF, -7.5 for RF/LF, -12.5 for 1B, -17.5 for DH
Fld + Pos
RAR - Runs Above Replacement (Batting + Fielding + Base Running + Replacement + Positional)
WAR - Wins Above Replacement

Pitching

RA9-Wins - Wins Above Replacement calculated using Runs Allowed
BIP-Wins - BABIP wins above average
LOB-Wins - Sequencing in wins above average (calculated as the difference between RA9-Wins and WAR minus BIP-Wins)
FDP-Wins - BABIP and Sequencing wins above average, also the difference between RA9-Wins and WAR
RAR - Runs Above Replacement
WAR - Wins Above Replacement


What Is the FanGraphs Library, and How Do I Use It?

After Dave Cameron’s introduction yesterday, I wanted to take a brief minute to explain the purpose and goal of the Library for those that haven’t seen it before. And before I begin, thanks to everyone for the kind words yesterday about the Library.

The Saber Library was initially created around a year ago, in response to some criticism we’d received at DRaysBay. Many (most) of our columns there deal with advanced stats, like the work done here on FanGraphs, yet many readers were having a tough time accessing the information and learning about sabermetrics. We’d tried running a saber primer or two, yet those could never be comprehensive enough to cover everything that needed to be said. Readers wanted to learn, but didn’t have a place to go to do so.

Read the rest of this entry »


Statistic Percentile Charts

How awesome is this chart? It’s simple, easy to understand, and imparts a swath of information all at once. I had no idea what league-average Isolate Power (ISO) was until now, but bam, there it is. This, my friends, is a thing of beauty. Until I saw this chart, I had no idea I needed all this information, but now that I’ve seen it, I want more.

I suppose I shouldn’t be surprised: this work of genius was created by Lee Panas, the writer at Tiger Tales and the author of “Beyond Batting Average”, a concise, well written book geared toward introducing everyday baseball fans to sabermetric statistics and analysis. It’s a great book and I recommend it thoroughly (although in the spirit of full disclosure, I must admit that I have a soft spot for Lee: not only am I a fellow saber-ed nut, but like Lee, I’m forced to root for my favorite ball team from afar, stuck in the wintery hellscapes of New England).

But I’m not writing this article as a book review (you can find those elsewhere); I’m writing because of that beautiful graphic up above. One of the complaints I hear most frequently from saber-newbies is that while they want to use these new statistics, they have no idea if the numbers they’re seeing are good or bad. Is a .320 wOBA good? Exactly how bad is a -5 UZR? I know it’s bad, but is it only mildly bad or tear-your-eyes-out bad? And what, pray tell, does a 4.00 tERA mean? It’s one thing to understand the theory behind the statistic, but sometimes understanding its scale can be just as challenging.

And so, I’ve taken Lee’s lead and included similar charts on each of the statistic pages here in the Library. The league-average rates are all accurate, and I’ve estimated percentiles based on the scores of all batters with more than 400 PA and pitchers with more than 90 IP. These percentiles may not be 100% accurate in all instances, but they are close enough to work as estimates in order to provide context.

Thanks again to Lee for the inspiration. If you like the charts, go check out some of his work.


Welcome to the Library!

Really, the Saber Library should never have existed. It took way too much time to create, cost me out-of-pocket money, was tedious as hell, had no tangible reward, and took away time from what I really should have been doing: finding a job. It was a project that most people in their right minds would never contemplate doing. Thankfully, though, I’m stupid.

When combined with large doses of boredom and time, stupidity can be a dangerous thing: a perfect storm for mayhem. In the ninth grade, my best friend experienced a particularly brutal convergence of these three things in bio lab one day, and stuck tweezers in the electrical socket to “…see what would happen”. Sparky eventually escaped his legacy by doing something even more stupid (breaking his leg during a chess match),  but so far, I haven’t been so lucky. Instead, I got to re-edit this entire thing for all you here at FanGraphs. Am I a sucker or what?

Thankfully, though, there are lots of smart people out there doing smart things that’s I’ve been able to steal from. Bradley Woodrum’s introduction to sabermetrics videos? Swipe! Graham MacAree’s incredible Saber 101 series? Stolen. Visuals from Justin Bopp at Beyond the Boxscore? Really, this is all too easy. Everyone’s been very gracious and willing to share, which has turned this site into a regular hodgepodge of smart things contributed by smart people. Trust me, I’m just as surprised as everyone else.

The Saber Library is now almost a year old and it’s here at FanGraphs to stay. I’ll be updating pages as FanGraphs changes, adding new statistics while changing the information on old ones, and I hope to make this a living, breathing resource. Consider it your Hitchhiker’s Guide to navigating the universe of sabermetrics (see what I did there?). While the math may be confusing and the Book Blog may give you a headache, this site is here to tell you “DON’T PANIC!” Things are not as complicated as they seem, and you don’t need to understand multivariable calculus to understand sabermetrics.

In the Library, you’ll find individual pages for nearly every statistic housed here at FanGraphs, along with a selection of primers on important sabermetrics concepts. We’ll also be using this space as a separate blog on FanGraphs (á la NotGraphs and RotoGraphs) and we’ll be writing articles geared toward helping people understand statistics. This space will (likely) not be updated as often as the other FanGraphs blogs, but we’ll see how this space develops.

And so, enjoy! Tour through the Library, learn something new, and whatever you do, keep those tweezers in your medicine cabinet.