Advanced statistics: a glossary

For some, this might look like alphabet soup, but here are a few of the advanced statistics that modern analysts are using to measure baseball performance:

What it tells you: If hitters and pitchers have been unlucky. The logic: A pitcher can't control what happens after the ball leaves his hand. Some bloopers fall between slow-footed outfielders. Some infielders steal would-be hits. On average, about 30 percent of the balls put in play (not counting home runs) fall for hits. So when a pitcher's BABIP is .335, as Francisco Liriano's was last year, it suggests he's due for some better luck.

How it works: The calculation is (hits minus HRs) divided by (at-bats minus strikeouts and HRs plus sacrifice flies).

Where to find it: fangraphs.com

What it tells you: How a pitcher handles the things he controls without help from his defense: walks, strikeouts, hit batsmen, home runs.

The logic: Some experts consider this a better predictor of a pitcher's future success than ERA. The formula tells you what a pitcher's ERA would be if his BABIP were league average. Liriano's ERA was 3.62 last year, but his FIP was 2.66.

How it works: It's a complex formula that adds more weight to a home run allowed than a walk, for example.

What it tells you: How much a hitter is producing, factoring in league averages and where and when he played. OPS combines a player's on-base percentage and slugging percentage into one number that gives a quick reference to his overall production. Adjusted OPS+ offers a way to compare players from different eras. The logic: A hitter at pitcher-friendly Dodger Stadium in 1968, when the mound was higher and scoring was way down, would fare much differently in 2003, during the height of the steroid era, playing in hitter-friendly Fenway Park.

How it works: The league-average OPS+ is always 100, and totals are adjusted from there. In 2009, for example, when Joe Mauer (above) won MVP honors, playing in the Metrodome, his OPS+ was 170 and Nick Punto's was 67. In 1967, when Harmon Killebrew finished second in the MVP voting to Zoilo Versalles, playing at Met Stadium, his OPS+ was 174. Versalles' was 52.

Where to find it: baseball-reference.com

What it tells you: How many runs a player saves or costs his team defensively.

How it works: Each play in every major league game is tracked by video analysts with Baseball Information Systems. The field is divided into 78 zones. Those analysts track the zone into which each ball is hit, whether it's a line drive, ground ball or fly ball. The data show how many plays are being made in each zone.

Where to find it: fangraphs.com

What it tells you: A player's overall value to his team, combining offense, defense and pitching. WAR has replaced win shares and VORP (value over replacement player) as the sabermetric community's favorite all-inclusive stat.

The logic: A replacement-level player is defined as a fringe big leaguer, the kind readily available for most teams at Class AAA. Think of former Twins catcher Jose Morales, whose WAR was 0.0 last year. This statistic measures how many wins the Twins gain by playing Mauer instead of Morales. In 2009, Mauer's WAR was 7.9, and last year, it was 5.1. The average full-time position player has a 2.0 WAR.

How it works: For a position player, the formula combines the runs he adds offensively with the runs he saves defensively. It adjusts for position, since first baseman are expected to produce more runs than shortstops, for example. Playing time matters, since Mauer's presence keeps a replacement-level player off the field. It also adjusts for league and park averages.