By Ray Flowers
January 19, 2009 11:01am CST

We are always on the lookout for new metrics which can help us to determine the value of baseball players. You may or may not be aware, but there are quite a few metrics out there that could help you to determine which hitters excelled last season, which efforts weren't as good as they might appear at first glance, and which players might be primed for a breakout campaign in the coming season. Some of the measures that we will discuss are fairly well known, while others may not be. Honestly, traditional baseball magazines, books and websites aren't necessarily concerned with helping you uncover new tools, as they often stick with the tired and true ways of reviewing players. While we will certainly provide you with that baseline information, we will also look to expose you to ideas, theories and measures that the mainstream sometimes avoids.

In this piece we will discuss a sabermetric measure which is used to gauge a hitter's overall effectiveness, and that is Bases per Plate Appearance, or BPA.


WHAT ARE PLATE APPEARANCES?

There are a plethora of metrics out there that can tell you how much power a guy has in his bat, how good a base runner he is or how many beers a guy could drink before passing out; but if they are so flipping complicated that you need to have a degree from MIT to understand them, what's the point? Luckily for you, Bases per Plate Appearance, or BPA is a simple idea that is pretty darn straightforward.

Just what is BPA? Well just what it says actually. BPA is a formula which presents a way to quantify how many bases a hitter earns per Plate Appearance (PA). Notice that this metric focuses on plate appearances and not the more traditional idea of at-bats. The reason is that we are concerned with every time a hitter comes to the plate regardless of the outcome of the event, so BPA considers such occurrences as walks and hit-by-pitch, events that count in the PA column but not in the AB one. Why do we care? Because we are interested in how many bases a guy picks up every time he comes to the plate, otherwise we would have to throw out walks because they do not count in one's at-bat total. To that end, here is the full formula for PA:

Plate Appearances = AB + BB + HBP + SF + times reached on defensive interference

With that understanding of why BPA uses PA instead of AB, let's move on to BPA itself.


BPA

Here is the formula for BPA:


(TB+BB+HBP+SB-CS-GIDP)
_________________________
(AB+BB+HBP+SF)


We told you it was simple, right? BPA measures which batters are capable of generating the most bases when they come to the plate - it really is as simple as that. BPA therefore would favor any hitter who has a high average, extra-base power and a discerning eye.


2008 SEASON


Here are the BPA leaders for 2008 based on 502 PA (the amount needed to qualify for the batting title, determined by 162 games x 3.1 PA per game).


.685 Albert Pujols

.636 Manny Ramirez

.633 Lance Berkman

.629 Hanley Ramirez

.625 Chipper Jones

.624 Matt Holliday

.623 Alex Rodriguez

.617 Milton Bradley

.615 Ryan Ludwick

.612 Carlos Quentin

.611 Grady Sizemore

.596 Adam Dunn

.593 Chase Utley

.593 Mark Teixeira

.591 Kevin Youkilis

.584 Alfonso Soriano

.581 David Wright

.581 Jason Bay

.578 Ryan Braun

.577 Carlos Beltran

* Not enough PA to qualify: Jayson Werth (.593), J.D. Drew (.583) and Chris Iannetta (.573).

Albert Pujols leads the way here, not a big shock when you consider that he was second in baseball in OBP (.470) and first in total bases with 342. The man who led baseball in OBP, Chipper Jones (.470), came in fifth here partly because injuries limited him to enough plate appearances to produce only 252 total bases, the 72nd-best mark in baseball.

As for the total bases angle, Ryan Braun was second to Pujols with 338, but he drops all the way to 19th on this list. The reason for that? Well, walking just 42 times certainly didn't help.

Manny Ramirez split his season between the Red Sox and the Dodgers, but overall he was No. 2 on the list. As amazing as his .636 number was, it was actually only .014 points better than his ultra-impressive career mark, which just so happens to be the 15th-best mark all-time for a batter with 3,000 plate appearances. Albert Pujols, by the way, is eighth all-time with his .646 mark, while Jim Thome is 17th at .620. As for one of the men involved in the process that sent Manny out west, Jason Bay produced the 18th-best mark in the game to join fellow Red Sox player Kevin Youkilis in the top-20.

Milton Bradley might have hit only 22 home runs with 77 RBI and 78 runs scored because of injuries that limited him to 126 games, but get used to seeing his name on these sabermetrically inclined lists, as his effort last season was special. His .617 was the first time his mark was over .600 for a season.

Notable missing players include the following guys.

Ryan Howard finished at .577, mere decimal points behind Carlos Beltran for 20th on the list, so we won't dog the big fella here. Ditto for Aubrey Huff, who posted a .576 mark, the best of his career.

Ian Kinsler, who had his season limited to just 121 games because of a sports hernia, posted a .575 mark, pushing his career mark to .530 through three seasons. That guy has potential greatness written all over him. Fellow Ranger Josh Hamilton came in just behind Kinsler at .571, giving the Rangers a massively impressive trio last season when you include the since-departed Bradley.

Miguel Cabrera finished in 42nd place amongst qualifiers at .548, below that of Tigers teammate Curtis Granderson (.554).

AL MVP Dustin Pedroia came in at .530, actually one point below Troy Glaus and his .531 mark. That's what happens when you only go deep 17 times with 50 walks (Glaus had 27 long balls and 87 walks).

And finally, Cody Ross of the Marlins finished with a .524 mark, which actually put him ahead of much bigger names like Bobby Abreu (.523), Vladimir Guerrero (.520) and Justin Morneau (.518) just to name a few.

To put last year's leaders in historical perspective see the end of this article for the all-time single season leaders in BPA.


MULTIPLE-YEAR TREND
For a little more perspective let's look at the leaders in BPA for the past three years since we are into threes in the fantasy world.

2006-08 Leaders
* Minimum 1250 PA

.653 Albert Pujols

.641 David Ortiz

.636 Ryan Howard

.634 Alex Rodriguez

.626 Chipper Jones

.620 Lance Berkman

.618 Carlos Pena

.614 Matt Holliday

.610 Carlos Beltran

.610 Jim Thome

.610 Hanley Ramirez

.605 Alfonso Soriano

.604 Manny Ramirez

.596 Grady Sizemore

.595 Adam Dunn

.594 David Wright

.594 Chase Utley

.586 Jason Giambi

.582 Mark Teixeira

.580 Miguel Cabrera


2008 TEAM LEADERS
(MINIMUM 300 PA)

TEAMS BPA Arizona .520 Justin Upton

Atlanta .625 Chipper Jones

Baltimore .576 Aubrey Huff

Boston .591 Kevin Youkilis

Chi Cubs .584 Alfonso Soriano

Chi White Sox .612 Carlos Quentin

Cincinnati .601 Adam Dunn

Cleveland .611 Grady Sizemore

Colorado .624 Matt Holliday

Detroit .554 Curtis Granderson

Florida .629 Hanley Ramirez

Houston .633 Lance Berkman

Kansas City .498 Alex Gordon

LA Angels .520 Vlad Guerrero

LA Dodgers .551 Andre Ethier

Milwaukee .578 Ryan Braun

Minnesota .526 Denard Span

NY Mets .581 David Wright

NY Yankees .623 Alex Rodriguez

Oakland .560 Jack Cust

Philadelphia .593 Jayson Werth

Pittsburgh .586 Jason Bay

San Diego .537 Jody Gerut

San Francisco .511 Fred Lewis

Seattle .504 Raul Ibanez

St. Louis .685 Albert Pujols

Tampa Bay .569 Evan Longoria

Texas .617 Milton Bradley

Toronto .500 Alex Rios

Washington .560 Elijah Dukes

ADDENDUM - BPA LEADERS SEASON, ALL-TIME

B.Bonds 2001	.907	B.Ruth 1924	.790
B.Ruth 1920	.885	B.Ruth 1930	.788
B.Ruth 1921	.885	J.Foxx 1932	.785
B.Bonds 2004	.882	T.Cobb 1911	.781
B.Bonds 2002	.869	T.Williams 1941	.781
B.Ruth 1927	.820	H.Wilson 1930	.770
B.Bonds 2003	.818	L.Walker 1997	.770
B.Ruth 1923	.818	J.Bagwell 1994	.768
L.Gehrig 1927	.806	B.Ruth 1928	.768
B.Ruth 1926	.801	T.Williams 1957	.767
M.McGwire 1998	.799	M.McGwire 1996	.765
R.Hornsby 1925	.795	L.Gehrig 1930	.761

* Minimum 502 PA