During 2010, Baseball-Reference unveiled a new feature: current and historical WAR values on each of its player pages. This WAR (referred to as rWAR) uses the same framework as FanGraphs’ version (fWAR) — in that it attempts to encapsulate a player’s total value to their team in one stat — but has three main differences:
● Pitcher Value. fWAR uses FIP to calculate WAR for pitchers — making it defense independent – while rWAR takes a pitcher’s run allowed and adjusts it for their opponents, team defense, park, and role.
For more on why we believe FIP is the best metric to use when calculating WAR, see the Library page on Pitcher WAR values.
● Calculating Defense (2002-Present). For recent seasons, each system uses a different defensive metric. fWAR uses UZR, while rWAR uses Total Zone. UZR is considered more accurate, but is only available from 2002 onward, while TotalZone values can be calculated for any player in baseball history. As such, fWAR uses UZR for every year from 2002 onward, and it uses Total Zone for earlier seasons.
● Baserunning. Both rWAR and fWAR includes base running, although they use different metrics. fWAR uses Ultimate Base Running (UBR), while rWAR uses a similar, linear-weights-based system.
As a result of these differences, rWAR values typically come in lower than fWAR values, meaning a 6 rWAR is more impressive than 6 fWAR. For more on the differences between fWAR and rWAR, please see the links below.
Links for Further Reading