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.

MLS: Techera’s hat trick; Gordon the hero (again) for Chicago

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VANCOUVER, British Columbia (AP) Cristian Techera scored three second-half goals and the Vancouver Whitecaps overcame several defensive errors to tie the New England Revolution 3-3 on Saturday.

Techera completed the hat trick in the 74th minute off a pass from striker Yordy Reyna.

The Whitecaps (4-5-5) are winless in five games and have just one victory in their past nine matches (1-4-4). New England is 5-4-3.

Vancouver trailed 2-0 early in the second half.

Whitecaps defender Aly Ghazal had an own goal and made a poor pass that helped set up a goal by New England’s Teal Bunbury. Another Revolution goal came after defender Sean Franklin mishandled a ball.

Techera made it 2-1 in the 49th minute off a cross from Marcel de Jong. Russell Teibert set up Techera again two minutes later, with Techera scoring on a header after goalkeeper Matt Turner stopped the first shot.

Bunbury gave New England a 3-2 lead in the 59th minute after Ghazal’s weak pass was picked off.

Cristian Penilla also scored for New England.


ORLANDO, Fla. (AP) — Alan Gordon broke a tie in the 82nd minute and the Chicago Fire beat Orlando City 2-1 on Saturday night.

Gordon settled Bastian Schweinsteiger’s cross with a couple of touches at 25 yards from goal and fired a rocket into the upper right corner past goalkeeper Joe Bendik’s outstretched hand.

Chicago’s Mohammed Adams was sent off in the 89th minute for violent conduct, but the Fire (4-6-2) held on from there, including six minutes of stoppage time, to end a two-game losing streak.

Orlando City (6-5-1) has lost three straight after winning six in a row.

Aleksandar Katai gave Chicago the lead on a free kick in the 13th minute.

Cristian Higuita tied it for Orlando City in the 28th minute, slotting a right-footed shot inside the far post after getting sprung free by Chris Mueller’s short pass to the right side of the penalty area.

Patrick McLain had four saves for his first MLS win.

Walker hopes young England squad proves more “streetwise”

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Kyle Walker, who finds himself one of England’s youthful elder statesman ahead of next month’s World Cup, believes Gareth Southgate‘s 23-man squad has a “different vibe” around it and hopes that vibe will aid in galvanizing the Three Lions when they arrive in Russia.

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

Iterations past, as Walker sees it, lacked a certain “streetwise” sense about them; not that they weren’t always a hard-working bunch, but that they lacked the understanding to play smarter, not harder, in certain moments.

Walker, who missed out on the 2014 World Cup due to an injury suffered not long before the tournament in Brazil, feels he’s matured a great deal during his first 12 months at Manchester City, under Pep Guardiola, and he’s ready to impart some of that wisdom on the rest of the squad, with the help of a few of his Man City teammates — quotes from the Guardian:

“The whole vibe around England now is completely different. It is a younger set of players and we are taking huge steps in the right direction but we still probably need to get more streetwise.

“English footballers are honest, they will run for 90-odd minutes, but that is not always what you need. Sometimes you need to rein back a bit and try and control the game with your passing.

“When we come up against Belgium, say, it could be a deciding game but we need to realize that we don’t have to score in the first 10 minutes. If you can control the game you can wait until the 80th minute or longer if necessary. I’m trying to bring that calmness from Manchester City, and so is John [Stones].

“I’ve adapted my own game a bit since changing club. I stay back a bit more. When I was at Tottenham the fans wanted attack, attack, attack but, if you send too many bodies forward, you are liable for the counter. With England we are working in training on controlling situations a little better. If we can make it work on the pitch we will hopefully have a good tournament.”

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

Whether or not Walker plays right back — where he’s spent the majority of his career — or on the right side of a back-three, he’ll be second-most senior member of a defensive unity which is nearly untested in major tournaments.

Of the nine defenders chosen in the squad, only Gary Cahill (58 – the only player over 40) and Walker have made more than 30 appearances for England. Of the 23 players chosen throughout the entire squad, the average number of caps won is 19.5.

Platini vows to return to soccer after “end of long nightmare”

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PARIS (AP) Banned former UEFA President and FIFA vice president Michel Platini says he is planning to return to soccer after Swiss federal prosecutors confirmed he was not being charged in an investigation into possible financial wrongdoing.

[ MORE: Real Madrid 3-1 Liverpool — Los Blancos make it three straight ]

Platini says in a statement it’s “the end of a long nightmare for my family and those close to me.”

Since September 2015, the former France midfielder had the status of “between a witness and an accused person” in criminal proceedings opened against then-FIFA President Sepp Blatter. No criminal case was ever opened against Platini.

The evidence related to Blatter authorizing FIFA to pay Platini $2 million in uncontracted back salary in 2011.

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

FIFA’s ethics committee also investigated Platini’s request to FIFA for pension contributions he was not entitled to. It was agreed by Blatter and added more than $1 million to Platini’s retirement fund.

Platini was eventually banned for four years, through October 2019. Both he and Blatter denied wrongdoing but Court of Arbitration for Sport judges refused to overturn his ban and that of Blatter’s.

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

The case meant Platini was removed from the UEFA presidency and he was barred from trying to succeed Blatter as FIFA president in 2016.

Platini, a former France captain and coach, says “I will come back: where, when, how? It’s too early to say. But I will come back into football.

“Because football is my life and I deny anyone the right to deprive me of my life,” the 62-year-old Platini says.

Neymar appears in good shape after first week with Brazil

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

The striker continued his recovery, dribbling and passing at high speed in Brazil’s last training session on home soil before the national team sets up camp in London on Monday.

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

[ MORE: Neymar “annoyed” by latest (and constant) transfer speculation ]

Earlier in the week, members of Brazil’s coaching staff said Neymar was fit to train but they tried to reduce pressure on him by saying it would take time until he delivered his best performances.

Left back Filipe Luis said Neymar did well in training but still needs to forget the injury.

“I had a serious injury in 2010 and I came back with fear. In the first chance I had in a game, I went with it all so I could lose that fear. I saw it didn’t hurt and I just forgot,” Luis said. “It will be the same with Neymar, the first time an opponent kicks him … he will forget it.”

In the first training session in Teresopolis, outside Rio de Janeiro, Neymar occasionally dragged his right foot onto the pitch. On Thursday he took his right boot off, sat down for a few minutes and looked upset. Once the football was underway, he seemed as fit as his teammates despite accidentally kicking the pitch with his injured foot. He soon afterward got back in action.

[ MORE: Messi: It would be ‘terrible’ to see Neymar at Real Madrid ]

In the first and only Brazil open training session, with fans screaming his name on the sidelines, a playful Neymar nutmegged right-back Danilo and flipped the ball over Luis’ head.

Throughout the week Neymar showed his finishing was sharpening, especially from close range.

After Saturday’s training Neymar welcomed his girlfriend, actress Bruna Marquezine, and family members to the Granja Comary training ground.

With Brazil players off duty for the rest of the day, Neymar is expected to take some teammates back to his mansion in Mangaratiba, near Rio.

The 20-strong squad will meet again Sunday morning at the Brazilian football confederation headquarters in a visit to their museum.

Players then travel to London hours later and will set up camp until June 8 at Tottenham’s training ground.