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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.
  6. 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 | No 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 | No Comments »

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 »

ABA Game-Winning Buzzer-Beaters Added to Basketball Reference

29th August 2020

In February Basketball-Reference added a list of every Game-Winning Buzzer-Beater in NBA history. Today, we're happy to announce that we've also added a list of every Game-Winning Buzzer-Beater in ABA history.
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Posted in Announcement, Basketball-Reference.com, Data, Statgeekery | 1 Comment »

Gap Years on Basketball Reference

14th August 2020

Thanks to work from summer intern Amy Huddell and the research of APBR President Emeritus Robert Bradley, Basketball Reference has greatly expanded its database of gap years for NBA players. Specifically we've added 704 new records in addition to the previous gap year data we had on the site. This includes mid-season career interruptions, first-season injuries and situations where they were still on the roster for their final season but did not play.

Often mid-season career interruptions are injury-related, such as Derrick Rose's ACL in 2012-13 or Greg Oden's various knee ailments. Occasionally there are other reasons like Robert Reid in 1982-83 voluntarily retiring to pursue the ministry or Red Morrison in 1956-57 who went into the construction business before making a return the next season. There are a couple of players such as Charlie Paulk and Dick Rosenthal who had gap years due to military service.

Notable end-of-career notes that we've added include Wilt Chamberlain sitting out his final year under contract with the Lakers and Alex Groza being suspended indefinitely for his involvement in the CCNY point shaving scandal.

Another gap year situation is players in international leagues between getting drafted and making their NBA debut, or players extending their careers internationally. Recent examples of this that were added in this batch include Patrick Beverley and Stephon Marbury.

We hope that adding this context to player pages helps people browsing the site understand their careers a little better. Thanks again to Amy Huddell and Robert Bradley for their help with this project. If you have any questions or suggestions, feel free to contact us through our feedback form.

Posted in Announcement, Basketball-Reference.com, Data, History, Trivia | 2 Comments »

Box Scores Since 1901 Now on Baseball-Reference

24th July 2020

As we were getting ready for 2020 Opening Day, the hard workers at Retrosheet announced their latest update, and we have gotten that new information added to Baseball-Reference as well as our Stathead Baseball tools. The highlight from the latest Retrosheet update is the addition of box scores from 1901 to 1903. This means that we now have box scores for every game in American League history, as the AL's first season was played in 1901. Retrosheet has also uncovered play-by-play accounts for games in 1916 and 1917, extending PBP coverage two more years back, although we should note 100% coverage remains limited to 1973-present. The new play-by-play allows us to further bolster our historical splits and event data.

With game log coverage back to 1901, we now have game logs for the entire careers of Hall of Famers Johnny Evers, Joe Tinker and Mordecai "Three Finger" Brown. We also now have the box score for Christy Mathewson's first no-hitter of his career, on July 15, 1901. Our Stathead Game Finder tools can now search back to 1901 as a result, and Mathewson appears as the 3rd pitcher in that time span to throw a no-hitter before their 21st birthday. Batting and Pitching Event Finder searches have been opened up back to 1916. Of the games we have PBP for in 1916 and 1917, Bill Hinchman leads with 3 walkoff hits in that span. Advanced stats tables that rely on play-by-play will also be extended back to 1916.

If you have any questions about our data coverage, you can always see it here. We're happy to have this new data on our sites and hope you enjoy it as well. Please let us know if you have any comments, questions or concerns.

And thanks again to Retrosheet!

Posted in Announcement, Baseball-Reference.com, Data, Features, History, Stathead | 1 Comment »

NCAA Tournament Starters Complete Back to 1977

16th July 2020

Thanks in part to work from our intern Ryan Sullivan, College Basketball Reference now has starter and reserve designations for all NCAA Tournament games back to 1977. We previously could only claim 100% starter/reserve data back to 1994. Of course, this supplements our Final Four starter/reserve data which is already complete back to 1955. This data can be searched in our NCAA Tournament Player Game Finder.

Some searches that can be updated with these additions:

- Sean Higgins joins the list of reserve players with 30 points in a game, reaching that mark in the Elite Eight of the 1989 NCAA Tournament. He also joins the list of players with 100 points off the bench in their tourney careers.

- Reggie Theus is one point shy of Donte DiVincenzo for most points scored as a reserve in a single tournament, in 1977 with UNLV.

We hope you enjoy this addition to the site. Please let us know if you have any questions or comments.

Posted in Announcement, CBB at Sports Reference, Data, History, Play Index, Trivia | Comments Off on NCAA Tournament Starters Complete Back to 1977

Triple-Doubles Added to Leaderboards & Player Pages

25th June 2020

Basketball-Reference has added Triple-Doubles to its leaderboards and player pages. This includes leaderboards for both regular season and postseason, and also franchise leaderboards.

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Posted in Announcement, Basketball-Reference.com, Data, History, Leaders | 2 Comments »