Measuring the value of a player used to be as easy as reading his

numbers on the scoreboard, in the Sunday morning paper or on the

back of a baseball card. The information age, however, has

revealed the limitations in such traditional stats. Without

venturing into the dizzying acronymic labyrinth of VORP (value

over replacement player), BRARP (batting runs above replacement

position), DIPS (defense independent pitching statistics) and

other advanced specialty stats that could scare off a jet

propulsion engineer, here is a look at what's in vogue--and

what's not--in the vast array of baseball stats.

WHAT'S IN

1. On-base percentage. An official stat only since 1984, OBP

(hits plus walks plus hit by pitches divided by at bats plus

walks plus hit by pitches plus sacrifice flies) is enormously

important because it tracks how often a hitter wins his duel with

the pitcher by not making an out. Contrary to the adage, great

hitters do not fail seven out of 10 times--that's a .300 OBP,

which is poor. Great hitters fail six out of 10 times (a .400

OBP), and extraordinary ones like Barry Bonds, at least for the

past three seasons, fail five out of 10 times.

2. OPS (on-base plus slugging). Adding on-base percentage to

slugging percentage tells the story of how well a hitter gets on

base and how much damage he does with his hits. It reveals how

much better Alex Rodriguez (.996) was last year than fellow

shortstops Edgar Renteria (.874), Nomar Garciaparra (.869), Derek

Jeter (.843) and Miguel Tejada (.808).

3. Strikeouts per nine innings. "Pitching is defense," Red Sox

general manager Theo Epstein says. "You can't separate them." The

outcome of balls put into play often depends on the range and

skills of the fielders or just plain luck (think bloop hits and

bad hops). Strikeouts, though, are defense independent; the

higher the rate of strikeouts, the less that pitcher relies on

defense and luck. A declining trend in strikeouts per nine

innings may be fatal for a pitcher, as was the case last year for

Mets lefthander Tom Glavine.

4. WHIP (walks plus hits allowed per inning pitched). The fewer

base runners allowed, the fewer opportunities for the opponent to

score. The Giants' Jason Schmidt was the only qualifier last year

with a WHIP lower than 1.00 (0.95). Bad news for the Orioles and

the Devil Rays: Six of the top 10 are in the AL East (Boston's

Pedro Martinez and Curt Schilling, Toronto's Roy Halladay and the

Yankees' Mike Mussina, Javier Vazquez and Kevin Brown).

5. Stolen base percentage. It's not how many bases you steal but

how successful you are. Playing for one run early in a game is

overrated in today's power game. The stat-minded A's and Blue

Jays, for instance, ranked 29th and 30th in steals last year

because they know not to risk the opportunity for a big inning.

"If you're stealing at less than a 75 percent success rate,

you're better off never going at all," wrote Joe Sheehan of

Baseball Prospectus. The team with the most steals, Florida

(67%), was below that mark; only three teams exceeded it.

WHAT'S OUT

1. Batting average. Wait a minute. Isn't the player with the

highest batting average considered the batting champion? Isn't

batting average one of the jewels of the prestigious Triple

Crown? Well, yes, and people once listened to music by having a

metal stylus skim across a rotating vinyl disc. The problem with

batting average (hits divided by at bats) is that it reveals

nothing about the type of hits (bunt singles count the same as

grand slams) or how many times a player reached base by walk or

by hit by pitch.

2. Runs batted in. RBIs are heavily dependent on a player's spot

in the lineup, how often his teammates batting in front of him

get on base and how well they run. Any player who hits in the

middle of a lineup and stays healthy should drive in 100 runs.

Half of the 20 AL players with 600 at bats last year did so,

while two others had 99. Carlos Lee of the White Sox and Jay

Gibbons of the Orioles, for instance, accumulated 100 RBIs even

though they made outs at a worse rate than the average major

league player.

3. Runs. Like RBIs, runs scored are strongly influenced by lineup

position and teammates' abilities. Moreover, the stat doesn't

reveal how responsible the player was for creating the run. The

man who scores after reaching base on a fielder's choice, for

instance, gets the same credit as the man who scores after

leading off an inning with a triple.

4. Won-lost record for pitchers. Many a 20-game winner owes his

milestone to generous run support from his teammates and, these

days, a strong bullpen. Andy Pettitte won 21 games for the

Yankees last season with the help of 7.04 runs per nine innings,

the second best support in the majors among ERA qualifiers. New

Yankee Javier Vazquez, who otherwise had better numbers (3.24 ERA

and 241 K's to Pettitte's 4.02 and 180), won only 13 games for

Montreal while getting 3.98 runs per nine innings, which ranked

83rd among 92 qualifiers.

5. Errors. Everyone knows a home run when they see one. An error,

however, or the mere possibility of one, is a Rorschach blot.

Official scoring is dreadfully inconsistent from park to park.

Moreover, errors tell nothing about a player's range or throwing

ability. Former Angels outfielder Brian Downing, for instance,

once held the AL record for consecutive games by an outfielder

without an error. He often was replaced late in games for

defensive purposes. --T.V.

SI.com

More on baseball's stat services plus scores, team schedules,

complete rosters and analysis from Tom Verducci at

si.com/baseball.

COLOR PHOTO: J. PAT CARTER/AP RISK MANAGEMENT Luis Castillo and the Marlins racked up a major-league-best 150 stolen bases last year, but did they run too often?