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  • Fangraphs vs Baseball Reference

    I've been trying to decide which of these is better. The main things that I've been considering is

    fWAR vs bWAR

    wRC+ vs OPS+


    Which do you all prefer?

  • #2
    Originally posted by Bleedthrough View Post
    I've been trying to decide which of these is better. The main things that I've been considering is

    fWAR vs bWAR

    wRC+ vs OPS+


    Which do you all prefer?
    wRC+ vs. OPS+ is an easy one. wRC+ is more accurate. It's based on the context-independent run value of every offensive event. OPS+ is just park-corrected and relative-to-league average OPS, which itself is a stat that has no theoretical basis for accuracy, but has been used so long that BBRef likes to keep it as a familiar link between analytics and more traditional stats.

    The two metrics track very well, though, with around 99% correlation if you use one season of all qualified players. Where they tend to differ the most is with players who receive a lot of intentional walks, because IBB count just like regular walks towards OBP, and therefore OPS and OPS+, whereas they generally count less in wRC+. (Technically, they aren't included in the wOBA calculation that precedes wRC+ calculation, but an IBB does count as a PA, so it does increase the player's weighted runs above average).

    As far as WAR goes, I don't think you can say either site is definitely better than the other. Their hitting metrics and I think baserunning metrics should be very similar, but they frequently differ significantly on defense. This can affect total WAR. Bellinger, e.g., is rated much more highly defensively at BBRef than at FG, and consequently he has a much higher WAR there. Trout always seems to be rated higher at BBRef, too, though not as much as Bellinger, this year. Generally speaking, if BBRef WAR for a player differs substantially from his FG WAR, it's probably largely because of the different way they evaluate defense.

    When it comes to pitchers, the two sites often differ dramatically. BBRef evaluates pitchers based on runs allowed per nine innings, RA/9, whereas FG uses FIP, fielding-independent pitching. RA/9 does not consider the role of chance and luck in runs scored, whereas FIP does, so the two measures of WAR can give very different results for a single season. E.g., at BBRef, Mike Minor has the highest WAR, whereas he's not in the top 10 at FG.

    Which is better? Over a single season, arguably luck plays a significant role, so RA/9 may not reflect a pitcher's performance as well as the FIP-based system. Over longer periods, luck usually averages out, and RA/9 seems to work better. FG recognizes this, and they actually provide RA/9 values, and show how their WAR can be calculated by adjusting those values with runs resulting from BIP (balls in play) and LOB (left on base). Also, many analysts at FG, when discussing pitchers, will refer to both RA/9 and the FIP-based system, or use an average WAR of the two.
    Last edited by Stolensingle; 07-11-2019, 04:16 PM.

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    • #3
      Originally posted by Stolensingle View Post

      wRC+ vs. OPS+ is an easy one. wRC+ is more accurate. It's based on the context-independent run value of every offensive event. OPS+ is just park-corrected and relative-to-league average OPS, which itself is a stat that has no theoretical basis for accuracy, but has been used so long that BBRef likes to keep it as a familiar link between analytics and more traditional stats.

      The two metrics track very well, though, with around 99% correlation if you use one season of all qualified players. Where they tend to differ the most is with players who receive a lot of intentional walks, because IBB count just like regular walks towards OBP, and therefore OPS and OPS+, whereas they generally count less in wRC+. (Technically, they aren't included in the wOBA calculation that precedes wRC+ calculation, but an IBB does count as a PA, so it does increase the player's weighted runs above average).

      As far as WAR goes, I don't think you can say either site is definitely better than the other. Their hitting metrics and I think baserunning metrics should be very similar, but they frequently differ significantly on defense. This can affect total WAR. Bellinger, e.g., is rated much more highly defensively at BBRef than at FG, and consequently he has a much higher WAR there. Trout always seems to be rated higher at BBRef, too, though not as much as Bellinger, this year. Generally speaking, if BBRef WAR for a player differs substantially from his FG WAR, it's probably largely because of the different way they evaluate defense.

      When it comes to pitchers, the two sites often differ dramatically. BBRef evaluates pitchers based on runs allowed per nine innings, RA/9, whereas FG uses FIP, fielding-independent pitching. RA/9 does not consider the role of chance and luck in runs scored, whereas FIP does, so the two measures of WAR can give very different results for a single season. E.g., at BBRef, Mike Minor has the highest WAR, whereas he's not in the top 10 at FG.

      Which is better? Over a single season, arguably luck plays a significant role, so RA/9 may not reflect a pitcher's performance as well as the FIP-based system. Over longer periods, luck usually averages out, and RA/9 seems to work better. FG recognizes this, and they actually provide RA/9 values, and show how their WAR can be calculated by adjusting those values with runs resulting from BIP (balls in play) and LOB (left on base). Also, many analysts at FG, when discussing pitchers, will refer to both RA/9 and the FIP-based system, or use an average WAR of the two.
      Great explanation. Thank you. So their RA/9 WAR is basically almost the same as BBRef?
      Last edited by Bleedthrough; 07-11-2019, 09:27 PM.

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      • #4
        Originally posted by Bleedthrough View Post

        Great explanation. Thank you. So their RA/9 WAR is basically almost the same as BBRef?
        In theory. It's not exactly the same, presumably because they use different formulas to convert RA/9 to wins. Pitcher WAR is very complicated, and I'm not as interested in pitchers as batters, and haven't take the trouble to familiarize myself with it thoroughly. Batter WAR is simpler. If you understand the wOBA formula, you're mostly there.

        Personally, I find FG more transparent. There are explanations for every metric, in the Glossary section, that are very clear and easy to read. BBRef has them, too, but I have trouble finding them on the site, I usually end up doing a google search to locate them.
        Last edited by Stolensingle; 07-12-2019, 09:49 AM.

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        • #5
          Originally posted by Bleedthrough View Post

          Great explanation. Thank you. So their RA/9 WAR is basically almost the same as BBRef?
          The biggest difference between RA/9 WAR and BBref WAR is that RA/9 WAR does not include any team defense adjustments. At its most simple - RA/9 is pretty much run prevention + playing time measure while BBref WAR is a run prevention + playing time + adjustments for team defense measure.

          All with other minor adjustments, etc.

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          • #6
            BBRef WAR is certainly the more ubiquitous one for obvious reasons.
            "It is a simple matter to erect a Hall of Fame, but difficult to select the tenants." -- Ken Smith
            "I am led to suspect that some of the electorate is very dumb." -- Henry P. Edwards
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