Baseball is probably the most misunderstood sport of all time. Just walk on over to the PD forums and take a gander, go to the local sports bar, or listen to the office water cooler talk (assuming it's not football season) and you can get a good gauge about just how incredibly off the general bandwagoner is.
After some comments here and there, but mostly the thread discussing replacement level got me thinking there should be an official VEB glossary of preferred stats to use when discussing players, trades, etc. Hopefully here we can discuss and come to conclusions on which stats to use so you don't look silly and we can ride our SABRmetric high horse all over John Q. Edmondsjersey.
First when discussing overall/general team quality most Statheads like to use a teams Pythagorean winning percentage. Basically this is just a simple formula that involves the Runs a team scores vs the runs a team allowed. "There is no explanation for the correlation between the formula and actual winning percentage in theory, rather the correlation has just been shown to work empirically". I personally like using this stat to see what a team needs to improve on and how they evolved or regressed throughout the years.
Most of us know or at least should know that man can not survive on Batting Average alone. Who would you rather have, a .287 hitter or a .278 hitter? Well if you chose the .287 you just picked Mark Loretta over Lance Berkman (okay that was predictable to almost everybody). If you must use average when discussing a player it is more accepted to use the trio of slash stats, AVE/OBP/SLG. If you don't understand why then you need to read MoneyBall or BP's Baseball Between the Numbers (where most sabr stats are explained in great detail). Often people like to use OPS instead of slash stats or if you want to get really fancy use OPS+, which is OPS with park-factor and you can find already calculated at the famedbaseball-reference.com.
One of everybody's favorite and seems to be the one that dominates is VORP or Value Above Replacement Player. As I already said, there is a 9 page explanation in BP's Book. Here's the long and short:
VORP is cumulative stat; additional calculations are required before using them to compare multiple player's potentials for future contribution. At the very least they must be normalized for PA. VORPr is rate stat, and therefore is slightly better for comparing players who have had a different amount of playing time as long as you account for sample size.
Replacement level = freely available talent. Basically If your player goes down, a team can replace them from the waiver wire or the farm.
How Replacement level is calculated = It's actually based on RC/27 (runs created will be expanded on later) and it's based yearly. Basically BP tracks each teams regular players, then their backups then compare. They've found that generally backups perform at around 80% (again this will change year to year and by position)
Since they use RC/27 to determine replacement level, there is a formula published (that they don't explain how they came up with it) to turn slash stats into replacement level.
VORP is OFFENSE only and does not consider defense and it DOES consider position played so ARODs vorp isn't technically comparable to Pujols vorp since VORP compares Arod to 3b-men and Pujols to 1b.
VORP is defined that way for a reason. A player putting up Hanley Ramirez numbers at SS is more valuable to his team than a player putting up those numbers at 1B, so if you are comparing "value" (IE trying to determine the league MVP) it is fine and common to use VORP.RC
One of my personal favorites is RC. The reason why its the easiest way to relate a player to a teams Pythagorean W/L. You can click on the link to see the different versions, but I just use Baseball-References.com already calculated ones, which he uses the "technical version".
Clutch hitting is still in dispute by BP because they can't empirically prove it yet. If you are a hardcore fan of clutch hitting then a lot of people like to use either WPA that is tracked by fangraphs.com OR Win Shares (they are calculated way differently and often thought as the same stat as WPA).
This blog isn't meant to tell you what to use, so I'm not going to expand any further on WPA/Win Shares and clutch in general, I'm just saying if you like "clutch" these are the most accepted stats for clutch.
Please don't use RBIs as a validation for a player. I like using RBI when only discussing a hit. BP tracks players performance in RBI situations, but even fans when RBI was created in the 20s knew that RBIs would be team dependent. If you are in a fantasy league that uses RBIs I like sorting players by RBI opportunities then try to balance who is the best with the most.
The scope of this blog was to inform readers of the most commonly used stats around here, maybe eliminate some, maybe add some. Also help myself understand or hammer out any details. If I have any info wrong or missing please feel free to add/discuss. Also, if you have a better way to data mine specific stats PLEASE add. A lot of times I have to copy/paste stats into a excel spreadsheet when there is probably a better way. If this blog is on the right track, next will come Pitching then Defense.
Team: Pythagorean W/L
Offense: Vorp, RC, Slash stats, OPS, OPS+
Clutch: WPA, Win Shares
NOT to use: Average alone, RBI