Advanced baseball statistics can be hard to understand and often contain more acronyms than the New Deal. Here is a list of 12 terms that are widely used with an explanation of what they measure:
WAR (or WARP, wins above replacement player)
WAR attempts to encapsulate the value of all players across all positions for a season: How much better or worse is a player than a theoretical call-up waiting in the wings? And how many wins did he add to his team's total that season compared to if he wasn't in the lineup? It takes into account a player's offense, defense and baserunning. Pitchers' WAR has its own metrics. Three websites — FanGraphs, Baseball Reference and Baseball Prospectus — have different variations of this statistic. They differ the greatest in what metrics they use to calculate a player's defense and how they evaluate pitchers. So a player's WAR on one website can be different from the others.
Good, bad and average: These are the general ranges across each version of WAR — below zero is replacement level; 0.0-2.0 is a bench player; 2.0-5.0 is a starter; 5.0-8.0 is an All-Star; and above 8.0 is MVP-worthy.
OPS (on-base percentage plus slugging percentage) and OPS+ (OPS plus)
OPS is a statistic that can sound more complicated than it is — it adds a player's on-base and slugging percentages together to show how often he reaches base and hits for power. OPS+ makes small adjustments to OPS and scales it to a more easily digestible number with 100 being the league average and each point up or down being 1 percent better or worse than league average.
Good, bad and average: That changes by year, but according to FanGraphs, an OPS of .570 and below is awful, .600 is poor, .670 is below average, .710 is average, .800 is above average, .900 is great, 1.000 excellent. For OPS+, 150 and up is excellent. 125-150 is very good. Below 75 is poor. Boston's Mookie Betts leads the majors with a 1.101 OPS.
wOBA (weighted on-base average)