As we approach the beginning of the 2020 season, we have made some updates to our Wins Above Replacement calculations.  You may notice some small changes to figures as you browse the site. As always, you can find full details on how we calculate WAR here.

Defensive Runs Saved Changes

Last week, we updated Defensive Runs Saved (DRS) totals across the site with new figures from Baseball Info Solutions.  The new methodology involves breaking down infielder defense using the PART system - assigning run values to Positioning, Air Balls, Range, and Throwing.  Under the new system, an infielder’s total DRS is the sum of his Air Balls, Range, and Throwing runs saved, while Positioning runs saved are credited to the team as a whole.  You can read more about the updates in the Sports Info Solutions blog.  The PART system applies to all infielders since 2013.

Folding these numbers into WAR, we see some significant changes for individual player seasons.  The 2019 Oakland A’s get even more recognition for defense on the left side of their infield, with shortstop Marcus Semien gaining 0.7 WAR and third baseman Matt Chapman gaining 1.6 WAR from the new DRS numbers, lifting both players above Mike Trout and into second and third place respectively on the 2019 AL WAR leaderboard.  Chapman’s 1.6 additional WAR represents the largest single-season change in this update.

On the other end of the spectrum, we see Adrian Beltre with the most significant drop in this update, losing 1.5 WAR in 2015.

Since we use DRS to measure the quality of a team’s defense, these new values also impact pitcher WAR values.  Team total DRS changed by as much as 46 runs for a given team and season - the 2019 Dodgers defense improved from 75 DRS to 121 DRS by non-pitchers under the new system.  Once applied to a specific pitcher, however, the changes to WAR are much smaller in magnitude than the changes to individual fielders. The most extreme example is Hyun-Jin Ryu, who pitched 182.2 innings in front of the 2019 Dodgers defense.  Considering the Dodgers defense to be 46 runs better across the entire season, and considering that Ryu was the pitcher for 13.52% of the Dodgers’ balls in play in 2019, we adjust our expected runs allowed for Ryu by 6.2 runs for the season. After following the rest of the steps in our pitching WAR calculation, the end result is a drop of 0.3 WAR for the season.  All other changes to pitching WAR from this change to team defense are smaller than Ryu’s 0.3 WAR drop in 2019.

Park Factors

Park factors for 2018 have been re-computed to include the 2019 season, since WAR uses a three-year average for park factors when computing pitching WAR.  The most significant change here is the Miami Marlins, whose pitching park factor rose from 90 to 95 (where <100 represents a pitcher’s park and >100 represents a hitter’s park).  José Ureña sees the biggest benefit from this, with his 2018 WAR rising by 0.7 wins. All other changes to pitching WAR from updated park factors are smaller than Ureña’s 0.7 WAR gain in 2018.

New Game Logs from Retrosheet (1904-1907)

Last month, we updated the site with new data from Retrosheet, including new game logs for players from 1904 to 1907.  Having game-level data allows us to be more precise in our WAR calculations, since we can consider the specific ballparks a pitcher played in and the opponents he faced.

Take Christy Mathewson in 1907 as an example.  Prior to this change, we used the league average (excluding his team) of 3.36 runs per nine innings as the expected quality of his opposition.  However, with game-level data, we can see that Mathewson’s actual opponents averaged 3.55 runs per nine innings, showing that Mathewson was probably used strategically and started more games against better opponents.  Indeed, Mathewson pitched in 10 of the Giants’ 22 games against the league’s best offense, the Pirates, as well as 7 of the Giants’ 22 games against the Cubs, the NL’s second-best offense. Against the Dodgers and Cardinals, who each struggled offensively and scored fewer than 3 runs per game, Mathewson pitched in just 8 games total.

Knowing this about his usage, we can set more accurate expectations for how many runs an average player would have allowed under Mathewson’s circumstances.  By adjusting the quality of his opposition, we expect an average pitcher to have allowed about 7 more runs over the course of the season, resulting in a bump of 0.9 WAR in 1907.  All other changes to pitching WAR from new game log data are smaller than Mathewson’s 0.9 WAR gain in 1907.

Baserunning and Double Plays from Play-by-Play Data (1931-1947)

When calculating runs from baserunning and double plays, we use play-by-play data from seasons where it is complete enough to credit players for things like scoring from first on a double, advancing from first to third on a single, and hitting into fewer double plays than expected.

In the past, we have taken play-by-play data into account back to 1948 for baserunning and double plays, because the data further back than that has been incomplete and could give players an advantage in their WAR simply by having more complete play-by-play records than their peers.  As this data has become more complete over time, we have moved this cutoff back to 1931. The data is still somewhat sparse for games that took place during World War II (1943-45), but we felt it was worth including those years as well.

Pete Reiser of the Brooklyn Dodgers was skilled at taking extra bases, and it showed in the play-by-play accounts.  In 1942, he took extra bases at a rate of 55%, compared to the league average of 45%. Additionally, the Dodgers were tied with the Cardinals as the league’s top scoring offense, so Reiser had many opportunities to put his speed to use.  He scored from first on doubles a league-leading ten times in just 15 opportunities, and also scored from second on a single 24 times, good for 5th in the NL that year, in just 29 opportunities. Using this play-by-play data while computing WAR gives Reiser an additional 1.2 WAR in 1942.  All other changes to batting WAR from this change are smaller than Reiser’s 1.2 WAR gain in 1942.

Caught Stealing Totals from Game Logs (1926-1940)

When crediting runners for how many runs they contributed with their baserunning, we take into account their stolen base and caught stealing totals.  Caught stealing totals are missing for many players between 1926 and 1940, but we have complete game logs for players in that span.

In the past, when we didn’t have a caught stealing total for a player, we would estimate how many times they were likely to have been caught stealing based on the league’s stolen base success rate and the ways the player reached base during the season.

We are now using actual caught stealing totals from the players’ game logs, so there are some changes for players who did considerably better or worse than we had been estimating.

Take, for example, Freddie Lindstrom.  In 1928, the Giants third baseman stole 15 bases, but his official season stat line does not have caught stealing available.  Previously, we had estimated that he was caught stealing 11.57 times, based on everything else we knew about his performance and the league he played in.  However, game logs indicate that Lindstrom was caught 21 times, nearly twice as often as we had estimated. This difference gets folded into our baserunning runs calculation and results in a drop of 0.4 WAR.  All other changes to batting WAR from this change are smaller than Lindstrom’s 0.4 WAR drop in 1928.

Biggest Career Movers

Hall of Famer Ernie Lombardi sees the biggest change to his career WAR with this update, sinking from 46.8 WAR to 39.5 WAR, a drop of 7.3 wins.  The largest gain goes to infielder Lonny Frey, who picks up 5.2 wins. Both these players played in the 1930s and 1940s and saw big changes because of their baserunning.  Lombardi is known for being one of the slowest runners in baseball history, and this update shows that the numbers back that reputation. Frey was a fast runner in an era where stolen bases were rare, so he has been underrated to this point when it comes to his baserunning contributions.

On the mound, previously cited Hall of Famer Christy Mathewson is the big winner.  As discussed above, his WAR now recognizes how his manager would use him against tougher opponents, and he sees his career WAR jump by 2.2 wins.  Barney Pelty experiences the biggest drop of 1.9 wins.

We’ve highlighted some of the more extreme changes here, but to see full lists of the largest changes to season and career WAR totals, please see the spreadsheet here.

We're very excited about these new additions and hope you enjoy them as well. Thanks to Baseball Info Solutions for their contributions. Please let us know if you have any comments, questions or concerns.

As we approach the beginning of the 2019 season, we have made some updates to our Wins Above Replacement calculations.  You may notice some small changes to figures as you browse the site. As always, you can find full details on how we calculate WAR here.

Openers

Last season, the Tampa Bay Rays popularized the concept of the opener, where the first pitcher of the game is expected to pitch considerably less than a typical starting pitcher.  The opener is followed by a “headliner” or “bulk guy,” who enters the game after the opener but takes on responsibilities similar to a traditional starting pitcher. The Rays found success with this approach, and several other teams followed suit.

Our Wins Above Replacement calculation treats starting pitchers and relief pitchers differently, since relief pitchers have much lower ERAs than starters.  The opener strategy throws a wrinkle into this, since the opener is not expected to go deep into the game and the headliner is, so we have a starting pitcher who is behaving more like a relief pitcher and vice versa.

Tom Tango posted some thoughts on this last year, and the discussion in the comments of that post produced a working definition for the opener:

1. Determine if we have an opener.  This pitcher must start the game and have either at most 2 innings pitched (6 outs), or at most 9 batters faced.
2. Determine if we have a headliner. This pitcher must meet two criteria:
3. Length of appearance: At least 4 innings pitched (12 outs), or at least 18 batters faced
4. Order of appearance: They are the first reliever, OR they are the second reliever, but the first reliever entered mid-inning, and the second reliever started the following inning

If both these pitchers exist, then we have a game with an opener and a headliner.  Both pitchers must exist; you cannot have an opener without a headliner, and vice versa.

Using this definition, we have updated our WAR calculation to treat openers like relievers and headliners like starters.  This change has been applied to all seasons since 1960, the first year we apply a starter/reliever adjustment.

Ryan Yarbrough, the Rays’ most frequent headliner, is an instructive case.  He pitched 38 games and 147.1 innings, but started just 6 times.  By the above definition, 16 of his relief appearances were as a headliner.  Prior to this adjustment, the Rays’ rookie had 0.9 WAR for 2018. After the adjustment, Yarbrough has 1.5 WAR.  The new calculation recognizes that Yarbrough is behaving more like a traditional starting pitcher, and holds his performance to the same standard it would if Yarbrough had started those games.

Park Factors

Park factors for recent seasons have been re-computed to be three-year rolling averages. For instance, 2017 Park Factors now encompass 2016-2018. This is something that needs to be done each year when the season ends.

Catcher Defense Prior to 1953

With help from Sean Smith of baseballprojection.com (and of an unnamed team front office) and baserunning statistics from Pete Palmer, we now have incorporated catcher defense for the years 1890 through 1952 based on stolen bases, caught stealing, errors, passed balls, and, from 1925 on, wild pitches.  Prior to this update, these players’ defensive abilities were judged only based on errors and passed balls.

Duke Farrell is a particularly noteworthy beneficiary of this change.  His career WAR rises by nearly 8 wins, because he played in an era (1888-1905) with a lot of stolen base attempts and did a better job of throwing out runners than his contemporaries.

This change also impacts pitchers’ WAR figures, since we have more information about the quality of defenses to take into account.  For instance, Jack Taylor and Kid Nichols of the 1904 Cardinals see their WAR numbers rise by more than a win each after accounting for the fact that their catchers threw out fewer runners than the rest of the league.  Indeed, the Cardinals’ primary backstop Mike Grady saw his WAR drop by two wins with this update.

On the flipside, legendary pitcher Cy Young loses more than 4 wins over his career after accounting for the above-average work his teammates did behind the plate throughout his career.

We’ve highlighted some of the more extreme changes here, but to see full lists of the largest changes to season and career WAR totals, please see the spreadsheet here.

Baseball-Reference keeps track of the birthdays of every active MLB player as well as the majority of historical ballplayers on our site. You can access today's birthdays by clicking on the Happy Birthday/Born On This Day link on Baseball-Reference's front page. You could already sort birthdays by birth year, years played in MLB, All-Star Game selections and other basic statistics. But now, we've added our Wins Above Replacement metric as an additional stat to sort by.

Since today's August 24th, let's give a spotlight to the top 10 players born on this day, ranked by WAR:

If you have any questions or suggestions, feel free to contact us through our feedback form.

As you browse Baseball Reference, you might notice some subtle changes to WAR figures on the site. There are four main reasons for this:

1. Park factors for recent seasons have been re-computed to be three-year rolling averages. For instance, 2016 Park Factors now encompass 2015-2017. This is something that needs to be done when seasons end.
2. We've incorporated restated and expanded fielding statistics from Sports Info Solutions. SIS's Defensive Runs Saved forms the basis for our Defensive WAR calculations since 2003. From 2011 on they recalibrated data using their timer measures to measure ball hang time. There was also some recalculation based on changing shift methodology. Though we're now publishing their catcher framing stat (Strike Zone Runs Saved), we have not incorporated it into WAR at this time.
3. Pitchers who received time as position players (whether PH or in the field) are now being treated as part-time pitchers and part-time position players. Previously we treated them as full-time pitchers. Some pitchers like Red Ruffing, Bob Lemon and Jim Kaat appeared in many games as a position player, pinch hitter or pinch runner. We used to credit these PAs as pitchers, which overvalued their offensive contributions. To handle this, we compute a percentage of time as a non-pitcher and make an adjustment.
4. Also, we have incorporated a good deal more Retrosheet data which has affected the years we can compute more advanced fielding and baserunning measures. We're now able to roll these measures back to 1953. Another important change is that with Retrosheet gamelogs back to 1908, we can now use their IP data back to that year to get starter/relief IP splits. Some pitcher WAR changes for 1908-12 are due to WAR now being calculated using gamelog IP rather than the "official" total listed on the player's stat line. The biggest difference here was the appropriately named Bugs Raymond. The "official" record credits him with 324.1 IP that season, but the gamelogs come out to 304.1, which significantly impacted his WAR calculation (see below). For further reading on discrepancies between "official" records and more recently produced gamelogs, please read this excellent explainer by Retrosheet's Dave Smith.

For further details on WAR and its calculation, please see this WAR explainer.

Read the rest of this entry

Our friends at Sports Info Solutions (formerly known as Baseball Info Solutions) have provided us with a pitch framing measure back to 2011, which we have added to Baseball Reference. Before I explain any further, if you're unfamiliar with the concept of pitch framing please read Mike Fast's 2011 article on the topic and Ben Lindbergh's 2013 follow up.

The stat that we have added is called Strike Zone Runs Saved. It represents the runs saved by catcher framing. In our tables, it's labeled RszC and it's available from 2011 to the present. While this statistic is a potential component of Defensive Runs Saved (and therefore WAR), please note that we have elected to not integrate this number into DRS (or WAR) at this time. We may elect to do so in the future, but for now we agree with Bill James's stance that waiting for further research is a good idea.

Read the rest of this entry

This article assumes a lot of prior knowledge about the discussion of Wins Above Replacement, you can catch up here

• How Baseball-Reference.com calculates WAR and how others do:
  WAR-Wins Above Replacement Explanation
  WAR-wRAA explanation
  WAR-Position Players
  WAR-Pitchers
  WAR-Runs to Wins (this is especially relevant)
  Competing WARs Comparison Chart
• My Answer to “I Don’t Like How Complicated WAR Is and How It Is Constantly Changing.” “WAR is Like GDP for Baseball”
• Bill James: Judge and Altuve, and then
  Bill James: MVP Followup
  Joe Posnanski: More on WAR, following up on Judge and Altuve.
• Dave Cameron's reply to James: Putting WAR in Context: A Response to Bill James
• Jonathan Judge at Baseball Prospectus wrote an excellent piece on variability in WAR: Prospectus Feature: Bill James vs. The Noise
• Bill James and I discuss on twitter what I think is the crux of the matter
• Rany Jazayerli on how WAR should handle luck

First off, none of us are here without Bill James. We are all at our very best merely Chaucer or Joyce to his Shakespeare. All sabermetrics predating him flowed into his work and all sabermetrics after him carries echoes of his work.

To the discussion at hand.
Read the rest of this entry

There's a few days that every baseball fan has saved in her Google Calendar. Opening Day, the All-Star Game, and Game 1 of the World Series all loom large, but another highlight of every year is the Trade Deadline.

This year's Trade Deadline looks like it could be a little slower and less star-packed than last year's, when stars like David Price, Cole Hamels, and Troy Tulowitzki were on the move. However, four of the six division leaders have a team within 4 games of them, and both Wild Card races are still wide opening, meaning a lot of teams are incentivized to make a deal. Read the rest of this entry

User Affairs Coordinator @ Sports Reference.

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Happy Holidays from Sports Reference

Here's to a great 2013 and a blessed 2014.

With Wins Above Replacement (WAR) gaining more prominence since last season, it's a good time to remind everyone about our WAR 2.2 guide:

• Baseball-Reference.com WAR Explained - This explains the basics of WAR, the philosophy behind the stat, and some of the changes we made to the formula the past few years.
• Weighted Runs Above Average (wRAA) Explained - This describes how wRAA, the core hitting stat of WAR, is computed.
• Position Player WAR Calculations and Details - This explains how we turn wRAA, Baserunning & Double-Play Runs, Fielding Runs, Positional Adjustment Runs, and Replacement level Runs into WAR for position-players.
• Pitcher WAR Calculations and Details - This explains how we take a pitcher's runs allowed & innings pitched, and turn it into WAR.
• Converting Runs to Wins - This further describes the process by which Runs Above Replacement (for both pitchers and position players) are converted into Wins Above Replacement.
• WAR Comparison Chart - This chart shows the differences between the WAR found here at Baseball-Reference and those from a variety of other sources, including FanGraphs & Baseball Prospectus.
• WAR Data Downloads - If you want to download the raw WAR data yourself and play around with it, you can also get the Batting and Pitching data from our site.

Many of the questions we typically get about WAR can be answered by reading the guide linked above.