Compromised numbers: Why the statistic you see may not be actual possession

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One of the amazing statistics to come out of last Wednesday’s UEFA Champions League match was the possession number. Barcelona was reported by UEFA was having held the ball 72 percent of the time, an amazing figure against a club of Chelsea’s caliber. For those who have tried to find significance to correlations between possession and victories, the number must have been both remarkable and beguiling. After all, Barcelona lost, giving more credence to the hypothesis’ main qualm: What if one team doesn’t care about holding the ball?

The next day, the possession story got even more confusing. Supreme stat overlords Opta reported that Chelsea had only managed 20 percent of the ball. What? Even less time in possession? How freakish is this data point going to get?

That, however, is not the story. At least, it’s the story in light of what Graham MacAree notes at Chelsea fan site We Ain’t Got No History. As he’s found out, Opta seems to be miscalculating possession; or, better put, Opta is not reporting a number consistent with the normal expectation for a possession stat.

The normal expectation: When one team has the ball, they’re in possession. I think we can all agree on this, right? This still leaves a lot of gray area. For example, who gets credit for possession when midfield chaos leaves neither side in control? Does one team get possession on a goal kick, when most goal kicks lead to 50-50 midfield challenges? And more broadly, what happens when play is dead but the game clock is running?

I’ve always assumed this is like a chess clock. When one team controls the ball, you hit a button that sends their dials turning. When the other fully regains possession, you hit a button. One clock stops. The other starts running. Those in between moments? They’re governed by one rule: Until possession changes, don’t touch anything.

That, apparently has nothing to do with Opta’s calculations. In fact, Graham’s research suggests Opta doesn’t even run a clock, which may be why they never report possession in terms of time. Instead, the relation between reported possession and total passes suggests Opta just uses passes. As Graham found out, if you take a team’s pass attempts a divide it by the game’s total attempted passes, you have Opta’s possession stat.

What does this mean? Let’s take a totally fake scenario. Barcelona plays three quick passes before trying a through ball that rolls to Petr Cech. It all takes four seconds, while Petr Cech keeps the ball at his feet for eight seconds before picking it up, holding it for five seconds, then putting it out for a throw in, which takes eight more seconds to put back into play.

Despite Barcelona having possession for only four of those 25 fake seconds, they’d have 80 percent of Opta’s possession (three good passes plus one bad, while Chelsea had only Cech’s unsuccessful pass). A logical expectation of a zero-sum possession figure would have that as either 16 percent or (if you credit the time out of play as Barça’s, since they’d have the ensuing throw) 48 percent Barcelona’s. Or, if you do a three-stage model (that’s sometimes reported in Serie A matches), you’d have 16 percent Barcelona, 52 percent Chelsea, and 32 percent limbo/irrelevant.

Of the three methods of reporting possession, Opta’s bares the least resemblance to reality; or, it’s the one that deviates furthest from what we expect from a possession stat.

Ironies being a thing these days, there are two here. First, Opta is the unquestioned leader in soccer data management. How could this happen?

Second, Opta isn’t trying to hide their methods. In fact, they’ve published a post on their site detailing not only their practices but their motivations and research, an investigation that found their approach “came up with exactly the same figures (as time-based methods) on almost every occasion.”

You would think two curmudgeons like Graham and myself would have found this, right? Graham had a reader point it out to him, while a representative from Opta magnanimously pointed me to the piece without the seemingly necessarily indignation of explaining how a Google search works. After all Graham’s work and head scratching – after my lack of work and similar head-scratching – we could have just gone to Opta’s site.

“We try to be as transparent as possible with this stuff,” Opta said when I asked them about it. Certainly, they should be commended being so up front about their methods. After all, they’re a business that makes money off their work. They don’t need to give away their secrets.

But that’s a secondary issue. The main one: Why is a data house like Opta, reputed as the industry standard, taking this short cut? Or, why haven’t they renamed their measure? Granted, the perception that it is a shortcut may have more to do with our expectations than their intent, though based on their defense in the post, it’s clear they do see this as an accurate way of describing possession.

Still, the number they publish is completely redundant to the raw passing numbers also distributed. Why put the measure out at all if not to check a “possession stat” box on a list of deliverables?

Opta’s possession stat shouldn’t be cited in reporting, and if it is, the word “possession” shouldn’t be used to describe it. Reader expectations for anything labeled “possession” are drastically different than what Opta’s producing. The number is confusing to the point of being misleading. It’s becoming counter-information because of its poor packaging.

Even though Opta’s post on the topic is 14 months old, most will be surprised to hear this “news.” It’s disconcerting for anybody who is hoping a SABR-esque revolution’s on the horizon. Almost all of the huge volume of data to which we have access has been useful, but where people are expecting something akin to linear weights to be published tomorrow, we can’t even agree on the terms (let alone the significance of them).

Graham probably puts it better:

I’m completely fine with keeping track of passing volume – I’ve done it before myself. What’s frustrating, from an analyst’s point of view, is that we’re being sold a dud. A statistic that ostensibly measures possession measures something that is not possession, and gets repeated as authoritative anyway.

And people wonder why football statistics don’t get taken very seriously.

Ronaldo staying at Real Madrid: “See you next year”

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MADRID (AP) — For a third straight year, Real Madrid are celebrating a European title with their fans.

Madrid brought the Champions League trophy home on Sunday and paraded it through the streets of the Spanish capital as thousands of fans saluted the newly crowned champions.

[ MORE: Ronaldo hints at Real Madrid exit | Bale does the same ]

Madrid was back in Spain after winning its 13th European title with a 3-1 win over Liverpool in Kiev on Saturday.

Players and team members participated in a ceremony at a local cathedral. After this they met with the city mayor and community president before addressing fans from a terrace at the Puerta del Sol square, one of Madrid’s main locations.

“It has become a routine to be here,” captain Sergio Ramos said. “Hopefully it will continue for many years.”

Cristiano Ronaldo, who after the final hinted he could be leaving Madrid, heard fans asking him to stay at the club.

“Thank you for all of your support,” Ronaldo told the crowd. “We made history, it’s time to be happy.”

The team then got on an open bus and paraded with the trophy until reaching the club’s traditional celebration spot, the Plaza de Cibeles, where fans had been waiting for the champions for hours.

[ UCL FINAL: Player ratings | Three things we learned ]

The players chanted “Campeones, Campeones” and “We Are Kings of Europe” along with the fans. Ramos and Marcelo carried the trophy across the walkway set up over the plaza’s fountain and draped the statue of the goddess Cibele with a Spain flag that carried Madrid’s name on it. Ramos also put a team scarf around the goddess’ head to huge cheers from the crowd as the song “We Are The Champions” was played.

The next stop was due to be the team’s Santiago Bernabeu Stadium, where nearly 80,000 fans were expected to attend a ceremony honoring the European champions.

The stadium was packed on Saturday with fans watching the match on eight big screens set up at midfield. Confetti blasted from a stage behind the screens when the players lifted the trophy in Ukraine.

Thousands had already made it to the Plaza de Cibeles right after the game in celebrations that lasted into the early hours of Sunday.

Madrid has won the Champions League in four of the last five years. It had beaten Juventus last season, and city rival Atletico Madrid in finals in 2014 and 2016.

Preview: USMNT hosts Bolivia in shadows of World Cup hype

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With the rest of the world’s premier soccer nations gearing up for next month’s World Cup in Russia, the U.S. men’s national team is set to host fellow non-qualifiers Bolivia in a futile friendly at Talen Energy Stadium in Chester, Penn., on Monday (6:30 p.m. ET), the Yanks’ fourth time out since that infamous night in Trinidad.

[ MORE: Ben Olsen confirms D.C. United’s interest in Wayne Rooney ]

Five days later (Saturday, June 2), they’ll face Ireland at the Aviva Stadium in Dublin, followed by a trip to Lyon, France, to face World Cup-bound Les Bleus (June 9).

Youth movement continues

Once again, the likes of Michael Bradley, Clint Dempsey and Tim Howard — senior figures for the last decade-plus — are nowhere to be found as Dave Sarachan completes his sentence tenure as interim head coach following Bruce Arena’s resignation in November. Back for the first time is 19-year-old Christian Pulisic, native of nearby Hershey, Penn., who with 20 caps is the joint-most veteran member (Joe Corona) of the squad.

Average age of the 22-man roster: 22.8 years old.

“As I’ve talked about throughout this process, the theme is to offer opportunity to this younger generation of talented players that have potential down the road with the program,” Sarachan said this week. “We’ve had first-time call-ups in every camp since November, and this is another extension of that. We’re going into the Bolivia game with newer faces along with a few familiar players as well.”

[ MORE: Ronaldo hints at Real Madrid exit | Bale does the same ]

Youngsters forging careers in Europe

The just-completed 2017-18 season was a promising, encouraging one for a number of American youngsters — some not named Pulisic, even — plying their trade for a number of sides around Europe.

22-year-old defender Matt Miazga completed his second season on loan to Vitesse, made 36 appearances between August and May (43 in all competitions), and played a pivotal part in the Eredivisie side qualifying for next season’s Europa League. Come this August, he’ll be hoping to impress Antonio Conte(‘s successor) and win his place in the Chelsea squad.

19-year-old midfielder Weston McKennie made 22 Bundesliga appearances (13 starts), plus another three in the DFB Pokal cup competition, for second-place Schalke. After undergoing surgery for a knee injury in January, McKennie returned in March to reclaim a full-time spot in the gameday squad and a semi-regular place in the starting lineup.

21-year-old forward Andrija Novakovich, another Yank out on loan (from Reading) this season, bagged 21 goals in 37 league appearances for second-division Dutch side Telstar en route to an appearance in the promotion playoffs. Novakovich made his USMNT debut against Paraguay in March.

20-year-old defender Cameron Carter-Vickers (Tottenham Hotspur) saw first-team action this season while on loan to Championship side Sheffield Wednesday; 21-year-old defender Erik Palmer-Brown signed for Premier League champions in January and spent the final four months of the season on loan to Belgian side Kortrijk; 18-year-old forward Tim Weah made his first-team debut for Paris Saint-Germain in March and made his first Ligue 1 start earlier this month.

[ UCL FINAL: Player ratings | Three things we learned ]

Potential lineup

—– Hamid —–

—- Lichaj —- Miazaga —- Zimmerman —- Villafaña —-

—- Gooch —- McKennie —- 

—- Rubin —- Pulisic —- Weah —- 

—- Novakovich —-

Neymar appears in good shape after Brazil training week

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TERESOPOLIS, Brazil (AP) Neymar has finished his first full week of training with Brazil in apparent good shape ahead of the upcoming World Cup after foot surgery.

[ MORE: Three things we learned from Real vs. Liverpool ]

The striker continued his recovery Saturday in Brazil’s last training session on home soil before setting camp in London on Monday.

Brazilian football confederation footage shows Neymar passing and dribbling at high speed in training that was closed to the media.

The Brazilian has been recovering from right foot surgery in March.

Brazil players will be off duty until Sunday morning. They travel to London hours later.

Heartbroken Karius issues apology to Liverpool

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Liverpool’s disappointing result in Saturday’s UEFA Champions League final can be chalked up to many factors, but all anyone will ever remember is Loris Karius‘ performance… and the goalkeeper knows it.

[ MORE: Bale brace guides Real Madrid to third straight UCL title ]

Karius issued this series of tweets on Sunday, declaring his disappointment from the team’s 3-1 defeat to Real Madrid, as well as an apology to the supporters and his entire club.

Of the two errors Karius made, the Real Madrid equalizer from Karim Benzema was certainly the more glaring.

After receiving the ball on a routine grab, Karius rushed his distribution from goal while Benzema read the play perfectly and stepped in front of the throw to get a foot on the ball.

The ball then deflected into the back of the Liverpool net, and changed the complexion of the match drastically.

While Karius’ mistakes cannot, and won’t, go unnoticed, the Reds were still reeling from Mohamed Salah‘s gruesome shoulder injury in the first half — which leaves the Egypt international’s availability uncertain for the summer’s World Cup in Russia.