While player turnovers have only been officially tracked in NBA games since 1977-78, team turnovers have been tracked in official scorer's reports for nearly a decade longer. Per the official NBA Guide, team turnovers have been compiled since 1970-71. However, the official NBA Guide also only shows team and opponent turnovers comprehensively since 1973-74. Team and opponent turnover totals for the 1970-71, 1971-72 and 1972-73 seasons have always been a bit of a mystery. Ostensibly the NBA has these totals, but for some reason they have never been printed in NBA Guides.

Well, we're proud to announce that this mystery has been solved and there's one man to thank: Harvey Pollack.

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An eagle-eyed user recently noticed that the True Shooting Percentage calculation we were using in our college basketball box scores seemed to differ slightly from the method we spell out in our glossary. It turns out we were mistakenly using the FT constant we use for the pro game (.44) in our college box scores, rather than the .475 that we spell out in our glossary and that we use to calculate season and career-level data for players.
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Thanks to our new data deal with Opta, we are now able to present xG and post-shot xG on our goal log pages for clubs and countries (look for it during the world cup). This data shows you the details of each of goal including the scorer, the body part used, xG, post-shot xG, any assist and the two players with goal creating actions prior to the goal.

We have the same information for goals allowed which allows you to see that both of the goals scored against Manchester City in the Champions League group stage were headers.

See our xG explainer for the full list of 120+ league seasons we've added this info for.

With Major League Baseball making a mad dash to complete the 2020 season, a number of norms and standards have gone by the wayside this season. Due to postponements, cancellations, and Canada's need for a quarantine of those playing America's Pastime, MLB has been forced to schedule what they've considered home games to be played on the road. In these games, the host team bats first and they often go through the charade of wearing their road unis while the traveling team wears their home whites. We handle these games in a certain way and this has led to confusion as to what the home and road records and splits represent on Baseball-Reference.com.

Our policy has been and remains that a team playing in their home park is the home team regardless of whether they bat first or second (we call these Home Team Batted First or HTBF). We feel that home and visitor refers to location and not batting order. In a neutral site game (of which there have been very, very few), the home team would be the team to bat last. Since 2007, there have been 19 games where the home team batted first, those are listed below.

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If you haven't read it already, please read Mike Lynch's rundown of our new Stathead/Baseball service. I'm going to lay out some of the background for this change and explain some of the changes.

As I laid out in our post from early March, we are making changes to our Ad-Free and Play Index products.

Here is the thrust of what we said in March.

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.

If you've looked at the cost of Stathead/Baseball vs the Play Index, you'll notice we've gone from $36/year (+ $20/year for ad-free) to $8/month. I realize this is a significant increase. As I said in my original post, we are extraordinarily reliant on ad revenue. Back in early March this seemed problematic. Now with the complete collapse of the advertising market it has the potential to be lethal. If you don't block our ads, you may have noticed that we now have more ads on our pages. This is in response to the downturn in ad revenue. Sports Reference is doing fine right now, but if we want to continue to succeed and also be aligned with the needs of our users, a healthy stream of subscription revenue is vital.

We also feel our products warrant this price. The only comparable products to our Stathead tools come from Elias and STATS LLC and would cost you $10,000+ a year to subscribe to. You could create your own from Retrosheet data, but that would probably take more than $8/month of your time to maintain.

We are using monthly billing for at least the first few quarters, so that we can monitor more directly the success we are having in recruiting and maintaining subscribers. We have discussed adding an annual billing option in the future.

For the time being, we will be maintaining both the legacy Play Index site (which has been free since the start of March) and the new site, but before too long we will take down the old Play Index site, probably late May. We are also working on converting the other Play Index sites. First will be hockey and then probably basketball after that.

We realize there aren't games being played and that you might be facing your own financial challenges at this time. Therefore, we are offering the first month free for all users. And then, until the leagues start playing games, we will be giving users the option of claiming additional free monthly subscriptions. We'll provide more details on the latter plan as we approach the time for subscriptions to be renewed.

If you are a current subscriber, we will be emailing you with information about how we will be converting your subscription to the new system and of course, we will provide your money back if you are unhappy with the conversion to Stathead that we are offering you. Our goal is to give you a more than fair deal and see you join us on stathead.com.

Please feel free to reach out to us if you have questions or concerns.

--sean forman

Regular Basketball-Reference users are well acquainted with the Play Index, which allows us to compare players across eras and slice and dice season-level data by many criteria. Today we are now introducing the WNBA Player Season Finder, which will be accessible from both the Play Index page and from our WNBA home page. We have WNBA stats back to the league's inaugural 1997 season, which means you can now search all of WNBA history with this tool.

Just like our NBA Player Season Finder, with the new WNBA tool you can do single-season, combined season and total season searches. For example, with the combined season search, you can now create franchise career leaderboards, maybe to see how far ahead in first place Tamika Catchings is among point scorers in Indiana Fever history. Or with the total seasons search, you can now execute a search like players with the most qualified seasons of 2 blocks per game; Margo Dydek and Lisa Leslie lead with nine seasons each finishing with that mark in their career.

Of course, current season stats are also searchable with the Player Season Finder, so you can give them some perspective with past stats. A'ja Wilson is burning up the league in her first WNBA season, currently averaging over 20 points per game. Here's a look at the others in WNBA history who finished with 20 points per game in their rookie season.

Stay tuned for more additions to the WNBA section of our site here on the Sports-Reference Blog. If you have any questions or suggestions, feel free to contact us through our feedback form.

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.
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Our historical performance data for professional leagues (affiliated minor leagues, independent minor leagues, fall/winter leagues, and other international leagues) is provided by and licensed from 24-7 Baseball and Chadwick Baseball Bureau. It incorporates the work of many stalwart baseball researchers, including Cliff Blau, Art Cantu, Frank Hamilton, Reed Howard, Kevin Johnson, Bob McConnell, Jack Morris, and Ray Nemec, as well as members of the Minor Leagues Committee of the Society for American Baseball Research. Perhaps most importantly, it builds upon the seminal work of Ed Washuta, who magnanimously provided the framework to make the whole thing possible.

As licensors of this data, Sports Reference LLC is not in a position to update and make corrections to the dataset ourselves. All proposed corrections are passed along to the Chadwick Baseball Bureau. Their focus is on making corrections for post-1960 data first and then pre-1960 data as time permits. This is largely due to the sheer scope of the project, but also for economic reasons. The economic value to us for information such as the 1929 California State League is minimal and likewise the market for licensing such data is effectively zero. We wish to have the most accurate datasets we can, but must operate within the economic constraints of what the market will bear.

We realize that this may mean that certain issues and errors may linger on the site for months or even years and apologize for all such errors.

You can use the Chadwick Bureau website to send corrections or changes to the data.

Good news for fans of zambonis, fighting, and the greatest video game of the 1990s: the NHL has finally returned! After a wild season last year, there are all kinds of juicy storylines to follow this year. Can the Pittsburgh Penguins become the first back-to-back Stanley Cup winners since the Detroit Red Wings of the 1990s? How will the San Jose Sharks bounce back from coming so close and falling short. Will Alex Ovechkin reach 1,000 goals? Can Connor McDavid build upon a promising rookie year and live up to the hype? What round of the Eastern Conference Playoffs will the Washington Capitals be eliminated in this year (I kid, I kid)?

This blog post will seek to answer none of those. Instead, this week, I wanted to dig into one of the major trends that's been sweeping across the NHL the last few years, among fans and front offices alike. I'm talking, of course, about the rise of advanced statistics.

If you're a sports fan, you're probably at least vaguely familiar with Moneyball and the advanced stat wars in baseball. And you may have read articles about how thinkers in other sports, like basketball, have used similar principles to deepen their understanding of the game. This movement has reached hockey in recent years, as researchers have uncovered several new ways of understanding the game beyond the traditional stats like goals, assists, and plus/minus. These new analytics can help us understand why a team is over or under-performing, and whether that performance is sustainable. They can also help us appreciate unsung players who do more for their team than we may realize, because they don't put up flashy traditional numbers.

So, with that in mind, here's some of the basics to get you started in the world of advanced hockey stats. Read the rest of this entry

UPDATE (Feb. 25, 2016): MLB has informed us that they will be updating Brach's 2015 holds total to 15 (matching us). MLB's Cory Schwartz commented: "We do credit Holds whenever the pitcher enters in a Save situation and leaves with the lead intact, so this was an oversight on our part."

It recently came to our attention that for the 2015 season, we credited Brad Brach with 15 holds. MLB, meanwhile, credited Brach with just 14 holds (NOTE: After reading this post, MLB has agreed that 15 is the correct number of holds for Brach in 2015). It was discovered that the difference was in the handling of the Orioles 5-4 win over the Mariners on May 21. Before we jump into the details, let's examine MLB's definition of a hold (bolding is ours, for emphasis):

"The hold is not an official statistic, but it was created as a way to credit middle relief pitchers for a job well done. Starting pitchers get wins, and closers -- the relief pitchers who come in at the end of the game -- get saves, but the guys who pitch in between the two rarely get either statistic. So what's the most important thing one of these middle relievers can do? "Hold" a lead. If a reliever comes into a game to protect a lead, gets at least one out and leaves without giving up that lead, he gets a hold. But you can't get a save and a hold at the same time."

UPDATE (Feb. 26, 2016): Please see MLB's updated Holds definition here

As you can see, this isn't really much of a definition at all. There's little in the way of criteria here, and it's also pointed out that the statistic isn't even official, anyways. In fact, there's enough confusion that MLB.com credits Cory Rasmus with 2 holds in 2015, but Elias (MLB's official statistician) credits him with 1 hold in 2015. We credit him with 2, for what it's worth. This "definition" provides enough room for interpretation that variance in recorded totals is not uncommon.

Being that the statistic is unofficial, explaining all of this might be a pointless exercise, but in an effort to be transparent, we at least want to point out what standard we are using to assign holds.

Our standard is to give a pitcher a hold any time they protect a lead in a save situation (meaning they could have been eligible for a save if they finished the game). Brach presents an interesting study in that May 21 game. Starter Chris Tillman pitched 3 innings and left with a 4-1 lead. Obviously, he was not eligible for the win due to Rule 10.17(b), as he did not complete 5 innings. Tillman was relieved by Brian Matusz, who allowed 2 runs in the 4th, but completed the inning of work and left the game leading 4-3, when Brach took the mound for the 5th inning. Brach completed 2 scoreless innings, but the Mariners tied it up in the 7th after Brach left the game. The Orioles eventually won the game.

With the benefit of hindsight, you could say that Brach would have been in line for the win (not the save) if he had finished the game, since he ended up being more "effective" than Matusz, which would make it nearly a lock that the official scorer would have given him the win. But, hypothetically, Brach could have given up 20 runs in relief, but maintained the lead, and earned the save (with Matusz getting the win). As unlikely as that scenario is, the point here is that we're not using hindsight in assigning holds. In our opinion, the opportunity for a hold is defined when you enter the game and is only removed retroactively if you are given the win.

To be as clear as possible: our policy is to credit a hold when a pitcher enters the game in a save situation and leaves with the lead (and is not later given the win by the official scorer).

As we bolded in MLB's definition of a hold, "If a reliever comes into a game to protect a lead, gets at least one out and leaves without giving up that lead, he gets a hold." It would sure seem to us that Brach's May 21st appearance fits that criteria.

2019-07-09 Update on Long Holds

We were silent on this issue earlier, but we do not give a hold in the situation where a reliever is only in line for a "long save". A long save would be the type where they pitch three innings with the lead to end the game. For example, on June 29th in London Yankee Nester Cortes entered a 14-6 game in the bottom of the 4th with two outs, and a runner on first. This is not a standard save situation. He then pitched three innings in relief and did not relinquish the lead. If he'd gone on to complete the game he would have received a save, but his appearance did not begin as a save situation as the save is dependent on him pitching three innings. We do not include these situations as save situations and do not credit holds in these cases. This is true of most record keepers, but we are aware that MLB gameday did give Cortes a hold in this situation.

This wonderful Hardball Times article spells out the many differences in how holds and blown saves are calculated. It turns out no two sources agree on any of the league totals for holds or blown saves.