As the 2023 season begins, 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.

New Data For Negro Leagues Players

Recently, we updated the site with the latest player records for Negro Leagues players. This update included biographical updates (such as full names, handedness, and birth/death information) but also added data for many new box scores discovered by the team at Seamheads. See the blog post for more details about the scope of this update.

2021 Park Factors

Park factors for 2021 have been re-computed to include the 2022 season, since WAR uses a three-year average for park factors when computing pitching WAR. The most significant changes here are the Milwaukee Brewers, whose pitching park factor fell from 101 to 98 (where <100 represents a pitcher’s park and >100 represents a hitter’s park), and the Los Angeles Dodgers, whose pitching park factor rose from 97 to 100.

The biggest gainers from these changes were Dodgers pitchers Walker Buehler (gaining 0.5 WAR for 2021) and Julio Urías (0.3 WAR), while Brewers ace Corbin Burnes saw his WAR decrease by 0.3 as we adjust American Family Field in Milwaukee from being a modest hitter’s park to a modest pitcher’s park. All other changes to 2021 WAR are smaller in magnitude than these three examples.

New Data From Retrosheet

Today, we are also deploying an update to past box scores, play-by-play, and game logs from Retrosheet, including play-by-play for 1,712 games that previously did not have play-by-play coverage, including 833 games in 1914, a season which previously had no play-by-play coverage at all. See the blog post for more details.

Biggest Career Movers

The top mover for position players in career WAR is Tommy Butts, whose career WAR is 2.8 wins higher after this update. Most of this value was from his stellar infield defense at shortstop. Hall of Famers Willard Brown and Buck Leonard experienced a gain of 2.1 WAR and 1.6 WAR respectively over their careers.

On the mound, we see Birmingham Black Barons pitcher Dan Bankhead leading the way, adding 2 wins to his career WAR total. Bankhead’s playing record has 41⅓ more innings pitched with the latest update.

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 have run an update on our data from our friends at Retrosheet on Baseball Reference. Retrosheet, which provides box scores and play-by-play covering most of AL/NL history, has significantly expanded the availability of play-by-play for the 1921, 1922 and 1923 seasons, and, for the first time, added play-by-play for 1914 season. Thanks to their efforts, we now have play-by-play for 65.41% of 1914 games (53% in the AL and 79% in the NL), 97.72% of 1921 games, 97.35% of 1922 games and 93.35% of 1923 games. Additionally, 38 other seasons between 1917 and 1971 have seen smaller improvements in play-by-play coverage. This is our first play-by-play for the 1914 season, so many of our statistical tables that need play-by-play in order to be calculated (win probability, situational batting/pitching, base-running/miscellaneous, batting against, etc) will now have rows for 1914 for the first time. The 1921-23 seasons previously had ~80% coverage and are now very nearly complete.

Check out our full play-by-play data coverage map.

The additional play-by-play is also available in Stathead. For example, we now have 9 walk-off home runs from 1914. Two of those were hit by Gavvy Cravath of the Philadelphia Phillies. On Cravath’s Home Run Log, you can see we now have play-by-play data (and therefore win probability added) for 18 of his league-leading 19 home runs. The most important of these 18 home runs (by WPA) was his walk-off home run on June 11 against the Reds. In the bottom of the ninth with two outs and the bases empty, he ended the game with a deep blast to center off Earl Yingling. It had a WPA of .468.

The one Cravath home run from 1914 that we’re missing (August 4) was also a walk-off home run. We know this thanks to the Tattersall/McConnell Home Run Log, a database of all homers hit in the major leagues since 1876. This third walk-off home run is not in the Event Finder because we do not have any other events for that game.

Cravath’s season WPA is 4.3, tops in the NL and second in the majors to Eddie Collins’ 4.7. On the pitching side, Jeff Pfeffer of the Brooklyn Robins leads the way at 6.4. You can check out the complete WPA stats for the AL and NL. These are subject to change as play-by-play for more games is added.

This new data, along with our recent Seamheads update, will also allow us to re-run our WAR numbers, so keep an eye out for that update this week.

Thanks to a recent updated provided to us by researchers extraordinaire Pete Palmer and Ken Pullis, Pro Football Reference now has team rushing attempts for almost every NFL game since 1940. Read the rest of this entry

Eagle-eyed Basketball Reference users may have noticed a recent addition to the site: WNBA Executives! Our data developer Charlotte Eisenberg identified the executive-chain (which we define as the executive in charge of player personnel decisions) for every WNBA franchise. This has allowed us to add several new features. For instance,  Carol Blazejowski now has a page documenting her draft picks, trades and free agent signing during her 13 years as the player personnel executive with the New York Liberty. Read the rest of this entry

Thanks to our partnership with the Seamheads Negro League database, we have released our second annual update of the dataset. Our last update, in April of 2022, was covered in this blog post. Like last year, this update includes thousands of incremental improvements. The most significant new data revolves around expanded statistics for the 1940 and 1941 seasons in the Negro American League and the Negro National League II. Additionally, lots of new biographical data has been added. Here's a rundown of some of the improvements Baseball Reference users will now see:

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Exciting news, we've just added even more women's stats to College Basketball Reference!

Just a few weeks ago, we expanded College Basketball Reference to include women's stats for the first time, covering seasons back to 2009-10. Today, we're excited to announce that we've added eight more seasons worth of stats, taking our coverage back to 2001-02. Read the rest of this entry

---UPDATED TO ACCOUNT FOR FULLER DATA SINCE 1990-91 ON 3/15/23---

While the NBA has only had a Defensive Player of the Year Award since 1982-83, it has named NBA All-Defensive teams since 1968-69. The All-Defensive teams allow fans to know which defenders were held in the highest regard, but don't necessarily tell us who was considered the best defender in a given season. Thanks to the research of Josh Elias and Sumitro Datta, we have added voting for the full history of the NBA All-Defensive teams, which allows us to get closer to answering that question.

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Late last year Basketball Reference added NBA Coach of the Year voting back to 1995-96. Thanks to the research of Josh Elias and Robert Bradley, we have now added voting for the award all the way back to the 1962-63 season, which was the first year of the award. Read the rest of this entry