Q&A for How to Read Baseball Statistics

It stands for "intentional base on balls," or an intentional walk.

"A" stands for "assist," and "PO" means "putout." A putout means retiring ("putting out") a batter or a base runner. There are various ways of making a putout, the most common of which are catching a fly ball, catching a thrown ball while tagging a base, tagging a runner, and catching a pitched ball for a third strike. A player gets an assist when s/he throws a ball to help make a putout (the exception being that a pitcher is not credited with an assist when s/he strikes out a batter).

This is not a universally-recognized baseball abbreviation, but it probably stands for "base-stealing average per attempt." It's better known as "stolen base percentage" and refers to the amount of success a given player (or team) has in attempting to steal bases (that is, the number of successful steals divided by the total number of attempted steals).

A batting average of ".256" is referred to as "two-fifty-six." An average of ".000" is called "zero." A batter who gets a hit in every at-bat has an average of "1.000" or "one-thousand."

They are footnotes, and are explained at the bottom of the box score.

Yes, there are many such books (not about the Cubs), among them: "Little League's Official How-To-Play Baseball Book" by Peter Kreutzer and Ted Kerley, and "Baseball For Dummies" by Joe Morgan and Richard Lally.

288 could be the number of hits made during a season. .339 looks like a batting average, and .562 might be a slugging percentage (number of total bases, divided by at-bats).

Those numbers usually represent his batting average, on base percentage, and slugging percentage.

"Wins above replacement" is a measure of how valuable a particular player is to his team. It is a rather subjective calculation of the number of times a player's especially effective actions lead directly to a victory.

Yes. A batter who hits a home run is credited with an RBI (as well as a run scored). He gets more than one RBI if there are runners on base when he hits the homer.

In Major League baseball determining a game's winning pitcher and the pitcher who is credited with a "save" can sometimes be complicated. To simplify, a winning pitcher is the one who last pitched prior to the half-inning in which the winning team took a lead they never relinquished. There are certain exceptions to that rule. One is that a starting pitcher must pitch at least five full innings to be eligible for the win. Determining a "save" is too complicated to be explained here. See the Wikipedia article "Save (baseball)" for the explanation.

There is no batting statistic that is negative. Perhaps you have misinterpreted what looks like a "negative sign."

It's hard to say without seeing the box score, but they probably refer to the pitcher's record of wins and losses or may refer to statistics from that particular game.

Left On Base is the total number of runners a team still has on the bases at the end of an inning (that is, the number of runners who failed to cross home plate before the inning ended). LOB for a full game is the sum of all a team's runners left on base in all of the innings.

This stat by definition, is considered a "hold". A hold is a baseball term for pitchers who can't obtain an official "save" yet were able to maintain the game's lead of 3 runs or less and record at least one out OR maintain it with the run on deck, at the plate or on bases and records an out. It is used by mid-innings relievers to keep the lead.

A "run" is a point scored and is credited to the baserunner reaching home plate. (The run is charged against the pitcher who allowed that runner to get on base in the first place.) "RBI" means "run(s) batted in," referring to any runs scored as the direct result of a given player's batting performance. In other words, if a baserunner scores because a hitter gets a hit (or draws a walk), that hitter is credited with an RBI.

It's a "sacrifice fly," which occurs when a fly ball is caught in the outfield, after which a baserunner "tags up" at a base and advances to the next base (typically home plate, where the runner scores a run).

Walks arent scored as a full at-bat. According to baseball's rules, at-bats are scored any time the player reaches base successfully via a fielder's choice (FC), hit or an error or during a play with a non-sacrifice.

App stands for appearance - if the pitcher came into the game (sometimes this may also equal the G stat - or total number of games (they appear in)). GS stands for games saved - if they performed a save - under a certain set of rules.