Baseball by the numbers: A closer look at WAR
BY JOHN GROCHOWSKI For Sun-Times Media July 1, 2013 8:28PM
Shortstop Alexei Ramirez is the White Sox’ leader in Wins Above Replacement at 1.2. | Charles Rex Arbogast~AP
Updated: August 3, 2013 6:26AM
In the last couple of weeks, after I’ve looked at All-Star Game candidates and Wins Above Replacement, email has been rolling in from readers wanting to know the whys and hows.
They want to know why replacement level is used. One reader wrote, ‘‘If they weren’t above replacement level, they’d be replaced, right?’’ And they want to know just what goes into the WAR calculation.
Replacement level is used as a baseline, a comparison point. It just as easily could be ‘‘wins above average’’ or ‘‘wins above All-Star.’’ In fact, at Baseball-Reference.com,
there is a ‘‘wins above average’’ column on each player page. Alexei Ramirez, the leader among White Sox position players at 1.2 WAR, is at 0.1 WAA. Anthony Rizzo, the Cubs’ leader at 1.7 WAR, is at 0.6 WAA.
But there are reasons replacement level is chosen as the touchstone. It reflects the kind of player who usually is easily available from the high minors or the scrap heap. If a regular is injured, a replacement-level
player is likely to take his roster spot. Average players are valuable, often carry expensive contracts and aren’t easily available in a tight spot.
Every roster is a mix of average,
above-average and below-average major-leaguers. Using WAA would mean getting into negative numbers for valuable major-leaguers. There’s no need to set the
baseline too high.
As for the WAR calculation, any real explanation is going to be long and detailed, as is Baseball-Reference’s tome at http://www.baseball-reference.com/about/war_explained_position.shtml. But let’s try a brief summary. It starts with calculating run values in several categories:
† Runs added at bat, for which Baseball-Reference uses weighted on-base average.
† Runs added on the bases, for which Baseball-Reference uses a formula explained in detail on the linked page.
† Runs added by hitting into fewer double plays than average or lost by hitting into more double plays than average. The formula is on the Baseball-Reference page.
† Runs saved on defense, for which Baseball-Reference uses Baseball Info Solutions’ Runs Saved. BIS charts where and how hard every ball is hit in every game.
† The total is adjusted for ballpark effects and for position.
† The result is compared to league average to get a player winning percentage. Following links from the page listed above can take you a page labeled ‘‘WAR Explained, Converting Runs to Wins.’’
A replacement-level player is defined as having a winning percentage of .294. A team of replacement-level players would go about 48-114 in a 162-game season. Pro-rated for playing time and translated for wins, WAR tells us how far above that .294 player any major-leaguer stands.
The point isn’t just that a player is above replacement level; it’s how far above replacement he stands. Is he at 2-plus, fairly normal for a starter for a full season? All-Star level of 5-plus? MVP-candidate level of 8-plus? WAR gives us a basis for those comparisons that incorporates the full game at bat, on the bases and in the field.