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.

Rapinoe named to USWNT roster ahead of April friendlies

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The U.S. Women’s National Team wasn’t at its best the last time they stepped out for the SheBelieves Cup, but Jill Ellis’ group will have a chance to find their feet again next month as they prepare to face Russia in a pair of friendlies.

[ MORE: Five questions for USMNT ahead of Honduras WCQ ]

Ellis announced her 24-player roster on Thursday, which was headlined by the inclusion of Seattle Reign midfielder Megan Rapinoe.

“This is our last chance to get together before the NWSL starts and we’ll take full advantage of the training time as well as the two matches against a team in preparation for the European championships,” said Ellis. “Following these matches, my staff and I will begin a heavy investment in attending and evaluating the NWSL games as well as tracking our players overseas before we get back together for our European trip in the summer. I’m very much looking forward to our domestic league starting.”

Back-to-back losses to England and France in the SheBelieves Cup gave the USWNT an unwanted start to 2017, however, the Russians will give the U.S. another strong test in April.

The USWNT will play the first of the two friendlies on April 6 in Dallas at Toyota Stadium before meeting the Russians three days later in Houston at BBVA Compass Stadium.

Here’s the entire 24-player roster for the USWNT ahead of their Russia friendlies.

Goalkeepers (3): Jane Campbell (Houston Dash), Ashlyn Harris (Orlando Pride), Alyssa Naeher (Chicago Red Stars)

Defenders (6): Meghan Klingenberg (Portland Thorns FC), Ali Krieger (Orlando Pride), Kelley O’Hara (Sky Blue FC), Megan Oyster (Boston Breakers), Becky Sauerbrunn (FC Kansas City), Casey Short (Chicago Red Stars)

Midfielders (8): Morgan Brian (Houston Dash), Tobin Heath (Portland Thorns FC), Lindsey Horan (Portland Thorns FC), Rose Lavelle (Boston Breakers), Carli Lloyd (Houston Dash/Manchester City), Allie Long (Portland Thorns FC), Samantha Mewis (NC Courage), Megan Rapinoe (Seattle Reign)

Forwards (7): Crystal Dunn (Chelsea FC), Alex Morgan (Orlando Pride/Olympique Lyonnais, FRA), Kealia Ohai (Houston Dash), Christen Press (Chicago Red Stars), Mallory Pugh (UCLA), Amy Rodriguez (FC Kansas City), Lynn Williams (NC Courage)

Shorthanded USMNT looks to build momentum against Honduras

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Avaya Stadium will have a different feel on Friday night when the U.S. Men’s National Team hosts Honduras as CONCACAF World Cup qualifying resumes.

[ MORE: Five questions for USMNT ahead of Honduras WCQ ]

USMNT manager Bruce Arena will be coaching his first competitive match with the Stars and Stripes since the 2006 World Cup in Germany, and now it’s his job to help guide the squad back to the World Cup after stumbling early on in qualifying under previous manager Jurgen Klinsmann.

[ MORE: Wondolowski grateful for USMNT call up after Wood injury ]

The U.S. currently sits bottom in the Hexagonal with zero points through its first two matches, while Friday’s opponent — Honduras — holds three points after picking up a victory over Trinidad & Tobago on Matchday 2.

Arena will have his hands full though, not only with the U.S. opposition, but also with his lineup, which is set to see some serious changes both due to injuries and suspensions.

Jermaine Jones won’t feature for the USMNT as he serves a yellow-card suspension against Honduras, while Bobby Wood, DeAndre Yedlin, Fabian Johnson and Brad Guzan are among those left off the 26-man roster after sustaining injuries in the lead up to the match.

There is some good news for the U.S. though, as Clint Dempsey, Tim Howard and Geoff Cameron return to the squad after going through their own injury layoffs. Dempsey has already scored twice for the Seattle Sounders since MLS action resumed earlier in March, while Howard has also found his form through the opening three weeks for the Colorado Rapids.

Meanwhile, Honduras will look to make matters worse for the Americans as Los Catrachos attempt to beat the USMNT for the second time on U.S. soil. The only time the USMNT has lost to Honduras in the U.S. was back in September 2001 when the Americans fell 3-2 at RFK Stadium in Washington D.C.

Several familiar faces will take the field for Los Catrachos, including five MLS players and various other former MLSers. Houston Dynamo trio Boniek Garcia, Romell Quioto and Alberth Elis all figure to play a role for Honduras, while Sporting KC’s Roger Espinoza and captain Maynor Figueroa of FC Dallas will also play dangerous roles for the visitors.

One name to keep an eye on will be 24-year-old midfielder Andy Najar, who now plays for Belgian side Anderlecht after previously plying his trade in MLS with D.C. United.

Schedule, preview for UEFA World Cup qualifying

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Three full days of 2018 World Cup qualifying are coming your way.

This will be a lot of fun.

[ MORE: 5 key questions for USMNT ]

Plenty of crunch qualifiers will be pivotal in deciding the fate of teams across Europe as just the top team from the nine groups goes automatically through to the finals in Russia, plus the eight best second-placed teams earn their spot in a home and away playoff for the four remaining spots.

The main game to look out for on Friday is the Republic of Ireland hosting Wales in Dublin with Group D finely poised. Ireland currently leads the group with 10 points but Austria is in second on eight points and Wales in third on six points. Just like he did at EURO 2016 (remember Chris Coleman’s Wales made the semifinals) Gareth Bale will be the talisman for the Welsh at the Aviva Stadium. Ireland knows that a draw isn’t disastrous but a win would put them in a very strong position to reach their first World Cup since 2002.

[ VIDEO: Podolski bows out in style for Germany

Elsewhere on Friday, Spain host Israel in Gijon with the Israeli’s knowing a win would take them above the Spanish in a very congested Group G that has Italy and Spain at the top on 10 points with Israel on nine. Plus Croatia welcome Ukraine to Zagreb in Group I with the hosts top of the group but a big away win for Ukraine would see them climb to top spot.

On Saturday three games stick out with the Netherlands heading to Bulgaria in Group A as Danny Blind’s men look to strengthen their grip on second place and try to hunt down first-place France. Meanwhile in Group B, EURO 2016 champs Portugal host upstarts Hungary in a similar scenario as Cristiano Ronaldo and Co. have nine points to Hungary’s seven but both trail leaders Switzerland who have a 100 percent record so far in qualifying.

Speaking of perfect records, Roberto Martinez’s Belgium host Greece in Group H with the talented Belgian outfit looking to make it five wins out of five in qualifying but Greece, who sit on 10 points, knows a win would see them leapfrog Belgium into top spot.

On Sunday England’s quest to make it four wins from five sees them host Lithuania in Group F as Gareth Southgate‘s men warmed up with a good performance but a disappointing defeat at Germany in a friendly. Elsewhere in Group F Scotland simply must beat Slovenia to have any chance of advancing to their first World Cup since 1998.

Group C leaders Germany head to Azerbaijan with Joachim Low’s men winning all four of their games so far, scoring 16 goals and not conceding in the process, while Northern Ireland host Norway in an intriguing clash as Michael O’Neil’s side hope to clinch second spot to continue their fine showing at EURO 2016.

Below is the full schedule for the next three days, while we will have reaction and analysis on all the World Cup qualifying games from the UEFA region.


Friday

Group D
Georgia vs. Serbia – 1 p.m. ET
Austria vs. Moldova – 3:45 p.m. ET
Republic of Ireland vs. Wales – 3:45 p.m. ET

Group G
Italy vs. Albania – 3:45 p.m. ET
Liechtenstein vs. FYR Macedonia – 3:45 p.m. ET
Spain vs. Israel – 3:45 p.m. ET

Group I
Turkey vs. Finland – 1 p.m. ET
Croatia vs. Ukraine – 3:45 p.m. ET
Kosovo vs. Iceland – 3:45 p.m. ET

Saturday

Group A
Sweden vs. Belarus – 1 p.m. ET
Bulgaria vs. Netherlands – 3:45 p.m. ET
Luxembourg vs. France – 3:45 p.m. ET

Group B
Andorra vs. Faroe Islands – 1 p.m. ET
Switzerland vs. Latvia – 1 p.m. ET
Portugal vs. Hungary – 3:45 p.m. ET

Group H
Cyprus vs. Estonia – 1 p.m. ET
Bosnia vs. Gibraltar – 1 p.m. ET
Belgium vs. Greece – 3:45 p.m. ET

Sunday

Group C
San Marino vs. Czech Republic – 1 p.m. ET
Azerbaijan vs. Germany – 1 p.m. ET
Northern Ireland vs. Norway – 3:45 p.m. ET

Group E
Armenia vs. Kazakhstan – 1 p.m. ET
Montenegro vs. Poland – 3:45 p.m. ET
Romania vs. Denmark – 3:45 p.m. ET

Group F
England vs. Lithuania – 1 p.m. ET
Scotland vs. Slovenia – 3:45 p.m. ET
Malta vs. Slovakia – 3:45 p.m. ET

PHOTOS: New aerials show rapid Tottenham stadium progress

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Tottenham Hotspur’s new home at White Hart Lane continues to take shape at a rather impressive rate.

[ MORE: Everton to get new stadium? ]

With this season expected to be Spurs’ final in their historic home, their stunning new 61,000 capacity stadium is being built around the Lane.

To anyone who has visited recently, Tottenham’s new home is starting to take shape.

[ MORE: A behind-the-scenes look at Spurs’ new home ]

All in all, it’s a very exciting time to be involved with Spurs as Mauricio Pochettino‘s men are in the FA Cup semifinal and are in second place in the Premier League table, 10 points behind leaders Chelsea.

On and off the pitch, the future is looking bright for Tottenham.

Take a look at the photos below for incredible aerial shots of the work, while the video above is from a recent episode of Premier League Download with Spurs.