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WNBA Transactions Added to Basketball Reference

8th June 2021

At the beginning of the WNBA's 25th season, we announced a huge expansion of the advanced stats and features available in our WNBA coverage on Basketball Reference. We are still working on more features, and today we're happy to announce the addition of transaction history to WNBA players and teams.

For example, you can now take a look at the 2021 league transactions page and catch up on big moves like all the trades that happened on February 10, including Natasha Howard to the New York Liberty and Kia Nurse plus Megan Walker to the Phoenix Mercury. One player with a lot of transactions added to her page is Shey Peddy. The draft pick she was selected with was traded twice, including a 5-team trade in 2011. Then, in 2019 and 2020 she made it through many 7-day contracts before finally signing a rest-of-season contract with the Mercury. Peddy went on to even hit the game-winner in a playoff game against her former team that season.

This transactions addition includes a couple of transaction types unique to the WNBA, such as 7-day contracts and contract suspensions. The latter is used in the WNBA to give teams flexibility and allow players to pursue international tournaments; Katie Lou Samuelson is a recent example of this transaction type.

We want to give special thanks to our data developer Charlotte Eisenberg and intern Christina Wiech for collecting and formatting this data, thus making this addition possible. We're constantly working to improve our coverage of the WNBA and the other leagues we track on Basketball-Reference, so if you have any suggestions or feedback, send us your thoughts via our feedback form.

Posted in Announcement, Basketball-Reference.com, Data, Draft, Features, History | No Comments »

Women’s Olympic Basketball Stats Now on Basketball Reference

14th May 2021

We are happy to announce the latest addition to Basketball Reference: we now have women's Olympics statistics back to 1976, the first Summer Olympics to have a women's basketball tournament. This complements our existing men's Olympic basketball data.

In the Teams section of our International index, a table has been added with each country's historical performance at the Olympics, in case you wanted to clear up how dominant the United States' women's team has been in this competition. There is also a women's Olympics seasons table that shows who got which medal in each competition.

We also have box scores for every women's Olympic match, from the first round robin games in the 1976 Olympics to the 2016 gold medal game between the United States and Spain. Players who participated in the Olympic Games, such as Lauren Jackson and Diana Taurasi, now have international pages.

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

Posted in Announcement, Basketball-Reference.com, Data, Features, History, Olympics at S-R | No Comments »

Sports Reference: Changing Player Identification Names from Player Nicknames to Given Names

30th April 2021

On Baseball-Reference.com we have begun the process of evaluating the identifying names and nicknames for historical players. The genesis of this process is the long overdue reckoning on our part with a substantial number of the names we use to identify players (identifying names). In many cases, they are based on a player's real or perceived ethnicity, a player's disability, or a trait the media decided to call attention to.

As a first step, we are discontinuing the use of nicknames that are racially or ethnically influenced, such as "Chief," "Jap," or "Darkie," and names based upon a player's disability, such as "Dummy." They will no longer appear as identifying names, page titles, on team pages, or on leaderboards across the site, but will be noted for completeness of records on the player’s main page. This figures most prominently for baseball, but we will likely have some changes on our other sites as well.

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Posted in Announcement, Baseball-Reference.com, Basketball-Reference.com, Data, Hockey-Reference.com, Pro-Football-Reference.com | 9 Comments »

WNBA Upgrades on Basketball-Reference

14th April 2021

The WNBA will be entering its 25th season of existence this summer and plans to celebrate the league's storied history. In preparation for this, Basketball-Reference is happy to announce a series of new upgrades to our site's coverage of the WNBA in the past and present.

One of the biggest additions is that we now have play-by-play data for WNBA games back to 2018. This allows for a lot of new features such as:

Quarter and half boxes in box scores
The play-by-play itself, along with a summary of lead changes, scoring droughts and scoring runs
Shot charts for the game, which includes filters by quarter and player
Shooting tables on player pages and league season pages that break down shots attempted and made by distance
Play-by-play tables on player pages and league season pages that detail on/off, turnover types, fouls committed and drawn and more

Other additions include:

A playoffs section: We now have a central playoffs table so you can quickly go through each season's Finals participants as well as postseason top performers in points, rebounds and assists. We also now have playoff summaries for each season that show all the series played in that postseason as well as team playoff stats and postseason individual leaderboards.

Expanded playoff statistics on player pages, including presentation of stats in per-36 minute and per-100 possession formats as well as advanced stats

Improved franchise history pages: Headshots displayed for top-12 in Win Shares in franchise history, additions to season history table such as SRS, pace, and top player in Win Shares. Links added for franchise leaderboards, all players in franchise history, franchise All-Star history, draft history and all-time head-to-head records

Team game logs and team splits pages

Game Highs table on player pages highlighting a player's best single-game performances in each statistic

We're constantly working to improve our coverage of the WNBA and the other leagues we track on Basketball-Reference. If you have any suggestions or feedback, send us your thoughts via our feedback form.

Posted in Advanced Stats, Announcement, Basketball-Reference.com, Data, Features, History, Leaders | No Comments »

2021 WAR Update

31st March 2021

As we approach the beginning of the 2021 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 Sports Info Solutions that incorporate more accurate hit timing data. This impacts some fielders from 2017 to 2020. You can read more about the updates in the Sports Info Solutions blog, including which teams and fielders were most impacted.

2019 Park Factors

Park factors for 2019 have been re-computed to include the 2020 season, since WAR uses a three-year average for park factors when computing pitching WAR. The most significant change here is the Cincinnati Reds, whose pitching park factor rose from 103 to 108 (where <100 represents a pitcher’s park and >100 represents a hitter’s park). Luis Castillo sees the biggest benefit from this, with his 2019 WAR rising by 0.7 wins. All other changes to pitching WAR from updated park factors are smaller than Castillo’s 0.7 WAR gain in 2018.

2020 Park Factors

When a season is in progress, our three-year average park factors are computed using a prorated combination of the current season and two years prior. Due to the shortened 2020 schedule, the park factors for 2020 were still using some data from 2018, because the 60-game schedule was being treated as a partial in-progress season. We’ve addressed this in our park factor calculations so that the 2020 park factors only include 2019 and 2020. This change was reflected in OPS+, ERA+, Rbat+, and rOBA in the past week, but it is now also incorporated in WAR, leading to small changes for a handful of players.

Lance Lynn gains the most from this, adding 0.3 wins with Globe Life Field moving from a slight hitters park (102) to a more extreme hitters park (107). Trea Turner has the largest change on offense, also gaining 0.3 wins with Nationals Park moving from being a slight hitters park (102) to being a slight pitchers park (98).

New Game Logs from Retrosheet (1901-1903)

Last summer, we updated the site with new data from Retrosheet, including new game logs for players from 1901 to 1903. 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.

We presented a more in-depth example of this in our last WAR update, when Hall-of-Famer Christy Mathewson’s WAR rose after we added new game logs. This time around, pitcher Doc White saw the biggest change, gaining 1.5 WAR over the course of his career.

Biggest Career Movers

The top mover for position players in career WAR is Trea Turner, gaining 1.8 wins through a combination of additional runs saved and beneficial park factor changes. Trevor Story is close behind at 1.7 wins, primarily through additional runs saved.

On the pitching side, we see Doc White with 1.5 wins gained as described above. Among modern players, Patrick Corbin saw his career total drop by 0.8 wins. This is the flipside to how Turner gained credit. Corbin is debited for playing in a more pitcher-friendly park than previously thought, and for playing in front of defenders like Turner who are getting additional credit for their defense. Both of these changes decrease the number of runs we’d expect Corbin to have allowed, and as a result his performance is not as valuable as previously calculated.

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.

Thanks to Baseball Info Solutions and Retrosheet for their contributions. Please let us know if you have any comments, questions or concerns.

Posted in Advanced Stats, Announcement, Baseball-Reference.com, Data, Features, History, Statgeekery, Stathead, WAR | No Comments »

Advanced Stats on Player Pages: How We Made It

26th February 2021

On Tuesday night, we added a new table of Advanced Stats to player pages.

This is what it looks like for hitters:

Mike Trout Advanced Stats

And for pitchers:

Gerrit Cole Advanced Stats

Rather than simply explain what we added, I’m going to describe how we added it. How does something go from an idea to a feature on Baseball-Reference? The entire process starts with you, the user.

At the beginning of January, we began conducting interviews with several users to discuss their experience using Baseball Reference and Stathead. By the time we launched the feature, we had spoken with nearly 50 users. It’s important to note that when we started the interview process, we didn’t have a particular solution or even a particular problem in mind.

There were several goals for these interviews. We wanted to find:

  1. What is the general perception of Baseball Reference compared with other sites?
  2. What features would users like us to add to Baseball Reference?
  3. What features would users like us to add to Stathead?
  4. What features of Baseball Reference and Stathead are users having a hard time using, finding, or just remembering to find?
  5. In what ways are people using our sites that we hadn’t anticipated?

Many of the interviews confirmed what we already knew. But every interview had at least one piece of gold that we could learn from. One interview in particular stood out to me and sent me on a path towards designing the feature you see on the site today.

I spoke with Mark Gorosh (@sportz5176 on Twitter) on February 3. Mark was lamenting that we don’t have advanced metrics such as BB% and K% on Baseball-Reference player pages. He didn’t understand why we had so many columns about the inner workings of WAR (in the Player Value table), but not established advanced stats like walk rate.

The issue, of course, is that we do have those stats. At this point I showed Mark the Advanced Batting page and… I’m not going to say Mark yelled at me, but he gave us some tough love that we really needed to hear. He couldn’t understand why all these great stats were not on a player’s main page.

And he was right.

There were a few different paths we could take.

  1. We could take all of the tables on the Advanced Batting pages and put them on the main player page. This wasn’t practical, however. There’s also an Advanced Fielding page and, of course, and Advanced Pitching page for pitchers. Adding all of these for a pitcher would lead to dozens of tables. Having so much on one page would negatively affect user experience.
  2. We could pick and choose certain things to bring over to the main page. Perhaps we could do this in a way that also leads users to click to the Advanced pages.
  3. We could move nothing, but focus on doing a better job of directing users to the player sub-pages (such as advanced batting and pitching, splits, and game logs).

We opted for the second option, but will also be looking to address the third option. The solution for the immediate job at hand is getting some advanced stats on the main player pages. But the fact that Mark (and other users) didn’t even know we had these advanced stats is a symptom of another issue—some users either are not noticing these sub-pages or they know about them but don’t think to use them (because they’re a click away).

This is a big deal because Baseball-Reference has a lot of users, but the super-users are the ones that have discovered the game logs, splits, and other advanced features. From there, they move on to Stathead to get even more powerful tools for their research. We want as many users discovering those features as possible so they can also turn into power users. So, in the future I’ll be looking to improve the player (and team and league) sub-navigation.

Now that we chose the path to explore, there were still different ways to proceed. One was to move the Player Value table (where we show WAR and its components) to the Advanced Batting page, but bring the most important columns (such as WAR, WAA, oWAR, dWAR, etc.) along with the most important columns from other Advanced Batting tables.

We began testing with that.

Francisco Lindor Advanced Stats Mockup

This early mockup tested well but some users showed a very strong preference for keeping the Player Value table where it was and adding a separate Advanced Stats table below it. Honestly, that was probably the right solution all along, but I wanted to see we could solve this without increasing the number of tables on player pages. We ended up adding one, but that’s fine.

There were several key things from this mockup that tested well, such as:

  1. The collection of stats we chose (which were the result of team discussions and also a survey we shared on Twitter).
  2. The addition of rOBA (our version of wOBA—Reference weighted OBA) and Rbat+ (our version of wRC+—based on the Rbat used in WAR). Despite the fact that these stats are brand new, I was impressed by how many guessed right away what they were.
  3. The links under the table to let users quickly jump to any table on the Advanced Batting page from the main player page. Not only does this help raise awareness of the Advanced Batting page, but also lets users know what tables are specifically on the page before they even go there.

The next version we tested kept all of these features, but put them in a separate Advanced Batting table. We also added base-running data, more batted ball data (such as the oft-requested Exit Velocity and Hard Hit %), and a row to display league averages for each stat (because users may not know what a good XBT% is).

That version of the mockup looked much like what you see today:

Francisco Lindor Advanced Stats

This version tested exceedingly well. Now it came down to building it. I asked Kenny Jackelen (@kennyjackelen on Twitter), Baseball-Reference’s developer, for a summary of the development process for a new feature like this. Kenny said he:

  1. Iterated multiple times with the team internally to get feedback on the table implementation (including how the table should render for players from different eras).
  2. Created new database tables for exit velocity data (which also powers the Hard Hit %)
  3. Added columns to existing tables to store rOBA and Rbat+ more permanently (previously these calculations were done as an intermediate step to get to WAR, so the database structure needed some updates to make it easier to pull them into the page-building process alongside other stats).
  4. Added logic to our play-by-play processing to assign batted balls a Pull/Center/Oppo location so that we can get a count of each type and compute the percentages for the Advanced Batting table
  5. Read a lot of slack messages in ALL CAPS from Adam D—like a marathon runner being handed a cup of water.

When it was ready, I got Mark back on Zoom to see his reaction. He said “it’s a 10.” He elaborated further, saying “It's not enough to be baseball’s best data aggregator. You have to present the information in a way that fans will be able to find it. I was honored that BRef and Adam took my suggestions to heart. The new player page designs put so many great pieces of data in easy to find places… near the top of the page.”

As a researcher, it was very fulfilling to come full circle with Mark. He went from tough love to delight.

As helpful as it was, not all user interviews revolve around tough love. Many users I have spoken with weren’t sure what to expect when they hopped on a call. Far more often than not, it’s just a casual conversation about baseball, the different ways people use the site, and what they’d like to be able to do.

I asked interview subject Jim Passon (@PassonJim on Twitter) if he had any thoughts on the interview process (so you don’t just have to take my word for it). He said “When Adam reached out to me to have a conversation about features that I’d like to see in the future, I couldn’t get the meeting set up quick enough. As expected, the meeting was awesome! I got to make a few suggestions, learn some new tricks, and catch a glimpse of the cool features that were already being developed for the site (which I absolutely loved). I now feel like I’m a part of my favorite site on the web... and that feels pretty good!”

Interviewee Jessica Brand (@JessicaDBrand on Twitter) echoed a similar sentiment, saying “I felt at ease, just discussing sports in depth in every which way with friends. It’s a great way to get those endorphins going to see and meet up with friends at your local stadium/arena/pitch you can’t necessarily see because of social distancing. Interviewing with Adam and Kenny provided the same warm and fuzzies.”

And honestly, in this time of social distancing and quarantine, hopping on the phone to talk about Baseball Reference with some of my favorite writers and analysts has been incredibly fulfilling. If you’d like to chat with me about how you’re using Baseball-Reference and Stathead, feel free to reach out at @baseballtwit on Twitter or go ahead and book a time on my calendar to chat.

Posted in Advanced Stats, Baseball-Reference.com, Data, Features, History, WAR | 2 Comments »

December 2020 WAR Update

14th December 2020

We recently fixed an issue where, because of the abbreviated 2020 season, we were not allocating enough wins to position players when calculating Wins Above Replacement. We have fixed this issue across Baseball-Reference. With this change, no position player gained more than 0.3 WAR, and no position player lost WAR. All pitcher WAR remained the same.

You can review the changes for each player here: https://docs.google.com/spreadsheets/d/18WY53wSt0GrBMMijLiIFMhVtvbmjuhbYNOaTvHfs-gE/edit?usp=sharing

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

Posted in Advanced Stats, Announcement, Baseball-Reference.com, Data, Statgeekery, WAR | Comments Off on December 2020 WAR Update

Kobe & LeBron’s High School Stats Now on BBR

10th November 2020

On Basketball-Reference, we have a special page for Michael Jordan where we house his statistics from his high school and college career. Two other superstars that have been in the spotlight since high school are Kobe Bryant and LeBron James, and we have added special pages for them that display their statistics during high school.

Kobe Bryant's high school page allows you to follow his improvement over his years at Lower Merion, along with notes marking milestones such as his first 40-point game or his McDonalds All-American honoring. The page also includes Bryant's preseason games for the first half of his NBA career. We give special thanks to Todd Spehr for compiling and donating these records and notes.

LeBron James' high school page tracks his statistics at Saint Vincent-Saint Mary in Akron before entering the NBA, with full coverage of makes, attempts and rebounds.

If you have any suggestions or feedback, you can contact us via our feedback form.

Posted in Announcement, Basketball-Reference.com, Data, Features, History, Trivia | Comments Off on Kobe & LeBron’s High School Stats Now on BBR

New International Leagues on BBR For 2020-21

27th October 2020

In addition to covering the NBA and WNBA in the United States, Basketball Reference covers an array of professional basketball leagues in Europe, Asia and Australia. For the 2020-21 season, we have added four new leagues: the ABA Adriatic League, the VTB United League of Russia, the Turkish Super League and the Israeli Super League. These leagues include teams that participate in the continental EuroLeague and EuroCup competitions, which we cover as well.

Notable former NBA players who are playing in these newly added leagues include Sam Dekker and Tyler Ennis with Türk Telekom in Turkey, Eric Mika with Partizan NIS in the Adriatic League, Greg Monroe and Jonas Jerebko with BC Khimki in VTB United, and Dragan Bender with Maccabi Tel Aviv in Israel.

For these newly added leagues we only have current season data right now, but if you'd like to see previous seasons for those leagues or express interest in other leagues, feel free to contact us via our feedback form.

Posted in Announcement, Basketball-Reference.com, Data, Features | Comments Off on New International Leagues on BBR For 2020-21

Introducing Football’s Premier Research Tool: Stathead Football

15th September 2020

In previous months, we have launched Stathead Baseball, Stathead Hockey and Stathead Basketball. Today, we're thrilled to announce that Stathead Football has joined our suite of Stathead tools, the most powerful set of sports research tools available to the public. In fact, they're so good that the pros (whether they're running teams or covering them) also swear by them.

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Posted in Announcement, Data, Features, Pro-Football-Reference.com, Stathead | 3 Comments »