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Archive for the 'Play Index' Category

Introducing Basketball’s Premier Research Tool: Stathead

27th July 2020

Today Basketball Reference is excited to announced the debut of the most powerful set of publicly available research tools on the hardwood. We're calling it Stathead Basketball and you can sign up for a free month of access here. Most of these tools may be familiar to some of our users from the Play Index. But Stathead also comes with the first of what will be many new additions: The Player Quarter Finder, which allows users to find the best performance in a quarter, or groups of quarters, since 1996-97.
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Posted in Announcement, Basketball-Reference.com, Play Index, Stathead | No Comments »

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 | No Comments »

Play Index Tools are Moving to Stathead.com

13th May 2020

The Play Index first launched on Baseball-Reference.com over thirteen years ago and has been one of the most used research tools for baseball ever since. Many of these tools have been recreated on our Basketball, Football, Hockey and College sites over the last twelve years, and, likewise, they have earned a dedicated user base of their own. Our Baseball Play Index was always a subscription product, but we never applied that model to the other sports' tools. It was always our intention to charge for these products, but for a variety of reasons that never happened.

The Sports Reference sites have continued to grow in traffic and advertising revenue over that time to the extent that the Play Index and our ad-free options are a very, very small portion of our revenue. Most of that is on us, as we have not done a great job of promoting and marketing tools that are highly valued by a dedicated group of users. The Basketball, Football, Hockey, and College Play Indexes represent well under 1% of our revenue. In addition, the Play Index tools are complicated to maintain and manage, and quite frankly are a money-loser for us at this time. It's well past time for us to re-think how these tools are positioned within our constellation of sites.

While Sports Reference is doing well overall, I'm not comfortable with having so much of our revenue dependent on advertising. We are very beholden to search engines continuing to send us traffic, and likewise the ad market can be fickle and difficult for a small to medium size operator to navigate. With the economic downturn currently taking place, our ad revenue is down significantly as well.

In addition, advertising on the sites does not make it easier for you to answer the questions you have. This is our primary mission. We maintain a relatively low level of advertising on the sites (at least compared to your regional newspaper), and we are loathe to add additional advertising units or more intrusive units. Some of you may use an ad blocker, in which case we are making no money from your use of the site at all, and the audience for our ad-free product has proven to be very small as well.

A subscription model aligns our interests much better with our users' interests as well. I realize that users are being asked to sign up for lots of subscriptions these days, but we feel the tools within the Play Index are so specialized and useful that they warrant a paywall.

So we are making some changes. The Play Index for each site will be moving to Stathead.com. Stathead.com will become the center for all of our subscription products. We expect these products to include tools and information beyond just a redesigned set of Play Index tools. This won't happen all at once, but we've started with baseball and are proceeding through the remainder of our sports over the next two months. Also, we have ended our dedicated ad-free product and instead Stathead memberships will have ad-free built-in. There just aren't enough users to justify a separate ad-free product. These changes will began in April for baseball and will be followed by Hockey in May, Basketball and probably Football in June and then College over the summer.

You can try out Stathead Baseball now. If you do a little digging, you will see that we are charging $8/month for a single sport and subscribing to all sports will cost $16/month. We realize moving from free to $8/month is a big ask, but we feel the tools provide a great deal of value and also believe that we can't continue to support the products without a viable revenue stream.

During the deployment of these changes, the existing Play Indexes will remain free.

--sean forman

Posted in Baseball-Reference.com, Basketball-Reference.com, CBB at Sports Reference, CFB at Sports Reference, Hockey-Reference.com, Play Index, Pro-Football-Reference.com, Uncategorized | 20 Comments »

Game-Level BPM In Play Index + Box Score Mouseovers

4th May 2020

In February, Basketball Reference made a major update in incorporating Daniel Myers' BPM 2.0, which aims to estimate a player's performance relative to league average by using a player's box score information and his team's overall performance. This statistic is also calculable at the game level, and we've made it easier to look through this by making BPM searchable in Basketball Reference's Game Finder, one of the many tools you can find in the site's Play Index.

BPM 2.0 is searchable back to the 1984-85 season, when we first have 100% coverage of all the statistical components needed to calculate this. It's important to note that BPM is a rate stat, so setting a minutes played threshold will be important. Here's a look at the top games in our system using a couple of different thresholds:

Minimum 10 MP

Query Results Table
Player Date Tm MP TRB AST PTS BPM
James Robinson 1996-12-30 * MIN 10 1 1 23 74.6
Henry James 1997-04-15 * ATL 10 2 1 24 63.9
Jrue Holiday 2009-11-24 * PHI 10 6 1 11 61.1
Provided by Basketball-Reference.com: View Original Table
Generated 5/5/2020.

Minimum 20 MP

Query Results Table
Player Date Tm MP TRB AST PTS BPM
Brent Barry 2006-03-24 * SAS 20 2 4 23 45.5
Manu Ginóbili 2009-01-20 * SAS 21 8 3 26 41.9
Victor Oladipo 2018-01-06 * IND 24 6 9 23 40.6
Provided by Basketball-Reference.com: View Original Table
Generated 5/5/2020.

Minimum 30 MP

Query Results Table
Player Date Tm MP TRB AST PTS BPM
Nikola Jokić 2018-10-20 * DEN 31 11 11 35 44.4
Gilbert Arenas 2006-02-25 * WAS 30 1 2 46 40.5
Damian Lillard 2016-02-19 * POR 31 0 7 51 38.1
Provided by Basketball-Reference.com: View Original Table
Generated 5/5/2020.

Minimum 40 MP

Query Results Table
Player Date Tm MP TRB AST PTS BPM
Damian Lillard 2017-04-08 * POR 42 6 5 59 35.7
Manu Ginóbili 2008-02-13 * SAS 41 5 8 46 34.2
Vince Carter 2001-05-11 * TOR 45 6 7 50 34.0
Provided by Basketball-Reference.com: View Original Table
Generated 5/5/2020.

In addition to the Game Finder addition, Basketball Reference now has mouseovers in the advanced section of box scores that display the offensive and defensive BPM breakdowns, as well as Value Over Replacement Player prorated to 82 games. For more information on how BPM 2.0 is calculated, please consult Daniel Myers' explainer. Stay tuned to the Sports Reference Blog for the latest additions to Basketball Reference!

Posted in Advanced Stats, Announcement, Basketball-Reference.com, Features, History, Play Index, Statgeekery | 1 Comment »

NBA Play-By-Play, Lineup and Shooting Stats Added Back to 1996-97

18th April 2020

Last August Basketball Reference extended its coverage of play-by-play all the way back to 1996-97 (the earliest season for which comprehensive, digitized NBA play-by-play data is available). As we teased at the time, we hoped to use the play-by-play to build out other features. In October we added the ability to break down our box scores since '96-97 by the quarter or half. Today we're happy to announce that many features that we've had available back to 2000-01 for many years have now been extended back to 1996-97.

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Posted in Announcement, Basketball-Reference.com, Data, Features, Play Index, Uncategorized | 5 Comments »

Advanced Player Game Logs on Pro Football Reference

10th April 2020

In 2019 Pro-Football-Reference added advanced statistics provided by Sportradar such as air yards, yards after contact, drops, and passer rating allowed among others. We have those available at the season level on player pages, as well as on the game level within box scores. We have now added advanced game logs, accessible from player pages, so you can see an individual's advanced stats at the single-game level.

Here are links to some examples:

Aaron Rodgers

Christian McCaffrey

Richard Sherman

If you have any questions or suggestions, feel free to contact us through our feedback form or Pro Football Reference's official Twitter account. Thanks for following us!

Posted in Advanced Stats, Announcement, Features, Play Index, Pro-Football-Reference.com | Comments Off on Advanced Player Game Logs on Pro Football Reference

2020 WAR Update

16th March 2020

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.

Posted in Advanced Stats, Announcement, Baseball-Reference.com, Data, Features, History, Leaders, Play Index, Statgeekery, WAR | 5 Comments »

Ad-Free and Play Index Changes Coming to Baseball-Reference.com

4th March 2020

The Play Index launched on Baseball-Reference.com over thirteen years ago and has been one of the most used research tools for baseball ever since. We've made a few additions over the years, but the tools have largely stayed the same and the price has only gone from $29/year to $36/year during those thirteen years.

The Sports Reference sites have continued to grow in traffic and advertising revenue over that time to the extent that the Play Index and our ad-free options are a very, very small portion of our revenue. Most of that is on us, as we have not done a great job of promoting and marketing tools that are highly valued by a dedicated group of users. The Baseball Play Index represents less than 4% of our revenue and ad-free memberships are less than 1%. In addition, the Play Index tools are complicated to maintain and manage, and quite frankly are a money-loser for us at this time. It's well past time to re-think how these tools are setup within our constellation of sites.

While Sports Reference is doing quite well overall, I'm not comfortable with having so much of our revenue dependent on advertising. We are very beholden to search engines continuing to send us traffic, and likewise the ad market can be fickle and difficult for a small to medium size operator to navigate.

Also, advertising on the sites does not make it easier for you to answer the questions you have. This is our primary mission. We maintain a relatively low level of advertising on the sites (at least compared to your regional newspaper), and we are loathe to add additional advertising units or more intrusive units. Some of you may use an ad blocker, in which case we are making no money from your use of the site at all, and the audience for our ad-free product has proven to be very small as well.

A subscription model aligns our interests much better with our users' interests as well. I realize that users are being asked to sign up for lots of subscriptions these days, but we feel the tools within the Play Index are so specialized and useful that they warrant a paywall.

So we are making some changes. The Play Index for each site will be moving to Stathead.com. Stathead.com will become the center for all of our subscription products. We expect these products to include tools and information beyond just a redesigned set of Play Index tools. This won't happen all at once, but we'll start with baseball and then proceed through the remainder of our sports. Also, we will be ending our ad-free product and instead Stathead memberships will have ad-free built-in. There just aren't enough users to justify a separate ad-free product. These changes will begin this month and continue through April on baseball and then continue with the other sites after that.

If you are a subscriber, we will make every effort to make certain you are happy with the options we provide to convert your ad-free or Play Index subscription over to Stathead including the option of a refund on your subscription. You will be hearing more from us about the changes over the next few weeks as we will email users directly.

During the deployment of these changes, the Play Index on Baseball-Reference.com (and the to be launched Stathead.com Baseball) will be free. They will continue to be free through at least April 30th. If you are a current subscriber to either of our products, we have already extended your subscription by an additional two months during this free period.

--sean forman

Posted in Announcement, Baseball-Reference.com, Play Index, Redesign, Statgeekery | 27 Comments »

Box Scores Since 1904 & Play-by-Play Since 1918 Now on Baseball Reference

20th February 2020

Thanks to the efforts of our friends at Retrosheet, we have added box scores back to the 1904 season to Baseball Reference. Previously, our game log coverage was back to 1908. Additionally, we have added partial play-by-play coverage for games games as far back as 1918. Previously, our oldest play-by-plays were from 1925. Since our last major Retrosheet update, the final two missing full play-by-plays of 1973 were added which means we now have complete PBP data back to that season now. In addition to the boxes and PBPs themselves, this update allows for a variety of new information searchable in the play index, as well as new rows of information in team/player/league statistics tables.

Here are some examples of the new information/searches available on the site.

If you have any questions about our data coverage, you can always see it here.

We're very excited about these new additions and hope you enjoy them, 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, General, History, Play Index | 7 Comments »

We Have Details on 99% of Triple-Doubles in NBA History

27th November 2019

As we continue to make efforts to flesh out as many historical NBA box scores as possible, one of the benefits is being able to capture many of the most outstanding individual efforts in NBA history. A prior example is that we have shooting numbers for all but one 50-point game in NBA history. Recently, we were curious to see how robust our coverage of NBA triple-doubles is. We're happy to report that we believe we have details on 99% of the triple-doubles in NBA history (well, technically it's only 98.6%, but we'll round up).

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Posted in Announcement, Basketball-Reference.com, Data, History, Play Index | 3 Comments »