Myths on the Pitch | Stats + Stories Episode 279 / by Stats Stories

Mat Dowsett is a Senior Expert in Lean Six Sigma with Roboyo, a global company specializing in automation and process improvement. In his free time, he is fond of the statistics side of process improvement and as a sports lover enjoys using statistics to answer tricky problems or to explore well-known myths. He recently authored an article in Significance about whether red cards can actually make soccer teams tougher.

Episode Description

There’s an idea in soccer that getting a red card and being down a player can actually make a team stronger. That going from 11 to 10 players forces a team to fight harder to protect their end and to hustle more quickly to score goals. But does that idea actually hold up on the pitch? Does the team actually become harder to beat? That’s the focus of this episode of Stats and Stories with guest Mat Dowsett

+Full Transcript

Rosemary Pennington
Just a reminder that Stats and Stories is running its data visualization contest to celebrate its 300th episode, you can grab data about the show to analyze and submit your entry at statsandstories.net/contest. Your entry has to be there by June 30.

There's an idea in soccer that getting a red card and being down a player can actually make a team stronger than going from 11 to 10. It forces a team to fight harder to protect their end and to hustle more quickly to score goals. But does that idea actually hold up on the pitch? Does the team actually become harder to beat? That's the focus of this episode of Stats and Stories, where we explore the statistics behind the stories and the stories behind the statistics. I'm Rosemary Pennington. Stats and Stories is a production of Miami University's Department of Statistics and media journalism and film, as well as the American Statistical Association. Joining me is regular panelist John Bailer, emeritus professor of statistics at Miami University. Our guest today is Matt Dowsett. Dowsett is a senior expert in Lean Six Sigma, with Reboil, a global company specializing in automation and process improvement. In his free time, he is fond of the statistics side of process improvement. And as a sports lover, he enjoys using stats to answer tricky problems or to explore well known myths. He recently authored an article in Significance about whether red cards can actually make soccer teams tougher. Matt, thank you so much for joining us today.

Matt Dowsett
You're very welcome. It's nice to be here.

Rosemary Pennington
What made you decide to do this project?

Matt Dowsett
So I love stats. And this should be pretty evident from the fact that this article is featured. And I love my sports as well, not just football, or soccer, as you call it. But cricket. I'm a big fan of cricket and pretty much any sport. And I love the fact that you can bring stats and sports together in such a valuable way. But let me just tell you a very quick story. I was on the phone to my brother, my older brother John, who supports Leeds United. If some people may have heard of Legion, I'm actually a Liverpool supporter myself. And we were having a conversation. And at the same time, Leeds United were actually playing. And he was very nervous because he wasn't sure if they would win. But I noticed on the score sheet that the other team had had a player sent off. And I said, Oh, it should, it should be great for you now, you should win now because the other team’s down to 10 players. And he said, Oh, no, no, no, no, it's always hard to play against him. 10 Min. And that always triggers me. And I said, I'm not so sure about that. I'm not so sure about that. And being the kind of person I am, I had to just go away and have a look at it. And I found another study that had been done previously in Significance. But I did think it's only used for season's worth of data and they even said within the article that it could do with some extra building upon it. And I thought there's a challenge. And so to answer my brother's question, but also to satisfy my own curiosity, and what we tend to see is quite often, especially related to sports, you're in a bar, you're down the pub, you're having a conversation with friends while the match is going on. And somebody will come out with something like that, an old myth, an old question. And it's very difficult to prove one way or the other. Some of those are the very best stories that you can have. But I quite liked answering them. So the short answer. The short version is I saw a challenge and I thought I needed to go and collect some data and answer that question. So basically it was proving your brother wrong. I wish it would have motivated me so no, no, no, no, absolutely not. No because I gotta get on very well with my brother and it was more the curiosity of can we show this one way or the other as well as proof of my brother wrong.

John Bailer
So as someone who played, you know, I played football. I coached it with kids playing at my you know, so from the card perspective, my younger son's perspective was a game without a yellow card was not a game well played. So his take was an intensity, but my older son, the striker, was more the one that would pick up the yellow card for mouthing off to a ref. Like one of my favorites was after he thought he had been found in the box and not gotten a card, he was running by the referee and said, Well, that's three of them now. And that led to an immediate yellow. So you know, maybe just to start we could just say how do these things like yellows and red cards come about because we may have some people that are listening that may know that soccer is a game where people are supposed to use their hands, save the two and then in the nets. But what does this whole card thing mean? And how does it play out?

Matt Dowsett
So yeah cards are there to give a punishment to players or to teams for infringements within the games that would otherwise be unfair or give them an unfair advantage. Yellow cards and red cards didn't used to exist in the game. And as a result, tactics were then employed, which allowed teams to manipulate the situation and get away with it, either by fouling other players repeatedly, knowing full well it would disrupt play and stop players, and so the yellow card and red card system was generated in order to have a method of penalizing teams for those infringements. And so the yellow card is effectively a warning. So it doesn't reduce a team to buy a player. But the red card does that, that player is sent off and they cannot return during the game. And so there is clearly an advantage numerically, to having to be playing against a team that has only 10 players or fewer as occasionally does happen.

Rosemary Pennington
I know it's always interesting when I'm watching matches, especially like the very high stakes ones where, you know, they'll talk about like, yes, that one's got two yellows, and this one isn't like the sort of the game and ship of like swapping players out to make sure someone they need doesn't get a red and then can't play the next.

Matt Dowsett
That's right. Absolutely, it does happen, especially in tournament play where there is what they call a totting up system. Where if you receive yellow cards in subsequent games, you will miss a game. And if that's a key player, and you're reaching a knockout phase, and you've got a really crucial game coming up to get to the final, you may act strategically and take the player out to make sure that they don't get another yellow card and miss the crucial game.

John Bailer
So one thing that we could talk about, I mean, certainly we have the Women's World Cup coming up this summer, we had just had the World Cup played in the euros or qualifiers or going on qualifiers for the World Cup or going in the next World Cup are going on as well. Yeah, so there's lots of play going on. And in fact, there was just a recent EPL game where we're, I think, man, you won when their component went down to nine players, after both a red for handling and a red for touching a referee.

Matt Dowsett
So that's right, that was Fulham. And there were actually three red cards within a short space of time, because their manager was also. So yeah, that was, yeah, hurting.

John Bailer
So tell us a little bit about the data that you compiled to start to explore this question of the impact of a red card on the outcome of the game.

Matt Dowsett
Yes. And I think one of the first caveats is that, as you just alluded to, sometimes there is more than one red card, and that can muddy the data. And so I first wanted to expand the dataset, not because I didn't, I thought it would prove anything greater or lesser, but it gives a better level of precision. And I think that's what happens with more data, you don't necessarily prove or disprove something in a greater way, but you get a higher level of precision. So I wanted to move from four seasons and red cards to a higher number, and so I selected 10 seasons. And then I cleanse the data by taking out instances where there was more than one red card, or where both teams had a player sent off, because of course that's a completely different question. And that left me with over 400 red card scenarios that I could work with. So I think the data that I got allowed me a certain level of precision. But without it becoming overbearing by being too much. It felt like it was a nice balance of data.

Rosemary Pennington
So can you talk us through what you did as you're trying to figure out whether there is an advantage for a team with the data player?

Matt Dowsett
Yeah, absolutely. And I think, as with all data, and as with all statistics, I think you always have to ask yourself the question, What am I trying to answer here? Because the pub question or the bar question of, is it better to be playing against 10 players, you then have to step back and say, Well, what are the variables that are involved in this? And how would I want to demonstrate that if I was answering the question, and so I started to break it down to say, Well, surely, if you are showing some kind of advantage, it will be in maybe in the final result. So a team that has a player sent off would perform worse in terms of a final result, and then would probably score fewer goals as well. And I thought those were probably the two angles that you would go down, the final result in the goal scored. And then there were other levels that you could add to that other variables that you could explore because of course, if you have a player sent off at the very last minute, and you're winning three nil, I think the score is very unlikely to change. However, if you have to play an hour with only 10 players, that is clearly, or it would seem to be, a clear disadvantage. And so the variables I wanted to start to pull all throughout. So, with the consideration of final result and goal scored, I felt that there were a number of variables such as the point in time at which it happened. Within the game, I thought it was a really crucial one. I thought that the existing state of the game as it was, was an important one. So was the team already winning? Or were they already five nil down, in which case, they're going to struggle, they were already struggling, they're going to struggle even more. And then there were the relative strengths of the teams. Because of course, if we're talking about a team that's at the top of the league, playing a team that's at the bottom of the league, there's already an advantage there, because by its very nature, there's a better team against the worst team. And the final one was about home advantage. Because I mean, I support Liverpool, who are notorious for having an amazing atmosphere where the home crowd is particularly loud, particularly rowdy, and it is considered to be the 12, the 12 player for the team. And I've experienced it. So was there some part of being home or away, that would also feature? So by breaking down? How I wanted to explore the question first, instead of just launching into throwing numbers around, it gave me a structure to work with, which would then help me answer the question in small clusters, which would then paint an overall picture of what I considered the final answer to be,

John Bailer
You know, at this point, I'm sure the listeners are just on the edge of their seats. So can you tell us a little bit about what you see and what kind of insights you have when you look at some of these outcomes? And some of these confounders or some of these modifying factors?

Matt Dowsett
Yeah, so instantly, let's talk about what happens at the end of all data without going in too, too complicated. A hypothesis test? Does a team that has got more players on the pitch, get more goals and more points? And the short answer is, yes, significantly. So a team that's had a player sent off will score just over a quarter of a goal on average, whereas a team that has got the player advantage will score at least one goal. And in terms of points achieved at the end of the game, the team that is at a disadvantage, will get less than one point, keep it in mind that you either get 01, or three points in football, and the team that has the advantage will score on average two points. And that is akin to being a relegation facing team playing a contender for the title that is on the straight lock. The disadvantage of having a player sent off makes you a relegation contender playing a title contender. And that is the headline view when you before going into any of the other nuances. So even at a glance, you can see there is a big disadvantage to having a player sent off.

John Bailer
You know, just as a quick follow up, I really liked the way that you then extrapolated kind of what that difference meant for an entire season. I thought that was a very effective way of communicating this kind of everage discrepancy in terms of goals scored for and goals allowed. And in terms of what it meant for the whole season. So I just wanted to say that I thought that was well done.

Matt Dowsett
Yeah, I think that's important to bring it to life as well. So people can understand what that actually means, in reality?

Rosemary Pennington
Yes, you're listening to Stats and Stories. And today we're talking to Matt Dowsett about stats and soccer. So this dataset you looked at was for the English Premier League, correct? That's right, now that you've done this work, have you had any thoughts about whether you want to expand it to the World Cup, or or Champions League in these other tournaments? Where, you know, stakes might cause teams to play differently? Or just teams that are, you know, different approaches to how to play the game are meeting one another?

Matt Dowsett
So in terms of red cards? Probably not. I think it is quite a focused problem statement. But I think there is a wider question here about how to win the World Cup. I think there's actually a dairy there. And I would love to do that one. Because when you consider what it takes to win the World Cup, or any other major tournament for that matter, what does it take to win the Euros? There are steps along the way, which will each have their own statistical nuances. So first, you've got to qualify. So what does it take to even qualify? And actually, do you get an advantage by being the host nation because many of the host nations have won the World Cup? England's a great example. So then you have to get through your group stage. What does it take? You know, if I was with Argentina in the World Cup, if you lose your first game, as they did, does that significantly reduce your chances of going on to win the tournament? Or does it have no bearing on it as with Argentina, they recovered from losing their first game and won the tournament. And then you have to get to the knockouts and face potentially the penalty shootout, you know, is there something in the statistics around penalty shootout? And then in the final itself, there will be, you know, as you were talking about, if you take the lead in the final, are you more likely to go on and win the final? Or actually do other teams come from behind to win. So, I think the kind of how to win the World Cup, or how to win a major tournament has a lot of nuances, a lot of elements to it, and also the backstories, which I always think because you can bring them to life by saying many teams have had a very poor start or scrape through a qualification, but then had the momentum to go on and win the tournament. So I think expanding it out to something a little bit more broad than red cards would be really interesting.

John Bailer
I suspect you could probably do the red card study in another league. I mean, the one thing that's different about some of these tournament plays, is you're looking at the tails of distributions, you're picking kind of the best of a bunch, you know, you’re picking the best of regions and World Cup. Yeah, you know, when you're looking at some of the various tournaments around Europe, it's the winners of the top finishers in their respective national leagues that are in competition, so it probably changes that game a bit. You know, one of the things that I thought was also interesting was looking at the status, the team state at the point of the red card. So if you're ahead, how often do you win when you're playing short? You know, if you were losing at the time? You know, it seems like that was just almost like you're dead meat, you know, if you're losing at the time when you go down a player, it certainly did not seem like you fared well. So, but you know, as you look at it, there doesn't seem like there's any real surprises there. But I thought it was so interesting to see it quantified.

Matt Dowsett
I think probably the biggest surprise was that there were still instances where teams that were losing when they got a red card did still go on to either get a draw or even win the game. That in theory, that the strength of having an extra player would argue that there was absolutely no way you could win from having a player sent off. And yet three of the teams did that, 11 of them managed to get a draw. What was also interesting was that some of the teams were able to hold on, if they were drawing, they were actually nearly half of the team that managed to hold on for a draw, even though they had a player disadvantage. So while on the whole, the statistics point to the disadvantage, there were still nuances. And there were still instances where you would say, wow, it actually a number of teams did still manage to hang in there and get a result. So yeah, the data tells its own story. But there are always those little quirks in there.

Rosemary Pennington
So I'm wondering, given what you've seen, and your experience being in the pub and hearing this myth, why is it that you think that this myth has persisted? Is it just because we are so emotionally invested in the sports we care about that we see one instance of someone coming back to win? And maybe it's our team? And we're like, yes, this must be the case that these teams are so tough when they're down a man like what? Why is it that we sort of hold on to this myth?

Matt Dowsett
Yes, I think it's a combination of seeing some small examples where a team has come from behind, despite having a player disadvantage and has gone on to win. There is also a lot of truth in the fact that tactics do change. So money managers clearly make tactical decisions when a player has been sent off to try to shore up the defense, and to try to hold on to what they've got. And so as a rule, and we see actually in the progression of the game, it does get harder to play, because the tactical decisions have forced that to happen. But what is often forgotten, because it's easy to forget is they've still gone on and lost the game. So, the myth endures because we see how it plays out. But we often forget the end result. So actually, it is harder to play against teams with 10 players, but they are still more likely to beat them.

John Bailer
You know, when you were looking at the surprising cases like the teams that were losing when they went to a player down or a team ultimately that was winning when they went to player down losing the match. Did you kind of dive into those particular teams? Are those unusual outcomes? And you say, Oh, well, maybe that makes sense to me. Because I mean, what was their sort of other story that could be told to kind of say, why did the counterintuitive occur?

Matt Dowsett
Yes. So it's very much down to two things. And the first is that home advantage that we talked about before. So there's those two of the factors, being at home can actually ever kind of have a bearing on it. It's not an enormous bearing, but it is a bearing. But the other part is the quality of the team. So more often than not a team that has come from behind to win, despite having a player sent off, has been higher up in the league. So what I did was I broke down the teams into four bins, because there are 20 teams in the Premier League, I took the top five, who would be the title contenders. The next five, so players teams six to 10, who would be the above average than the below average teams, the 11 to 16. And then the bottom five, who would be the relegation contenders. And what I saw when I ran the statistics of how they fared against each other, was that a top team, despite having a player sent off, would always perform better against lower opposition. And so that is the other fact that I found is the quality of the teams. So it's very rare for a top team. It is very rare for a bottom team, who has had a player sent off to reverse a scoring situation against a top team. Those instances where teams did very well were largely against inferior opposition. So being higher up the league is a clear advantage.

Rosemary Pennington
So you mapped out earlier a book that you might write about how to win a World Cup. What other stat, short stories, do you want to investigate? The two goalmouths like what else is on the agenda?

John Bailer
This could be for PI quiz night.

Matt Dowsett
So I'm going to I'm going to preface that by explaining what I think are the two best sports or the two sports in the world that are most suited to statistics. And you can agree or disagree here. The first and they're very similar, by the way. The first is cricket, English cricket, cricket that is played largely by England and Commonwealth countries. The second is baseball. And they are very, very similar. And the fact that they have a very stop start nature where each particular ball that is bold, is in itself an activity that generates statistics that lends both those spots to real statistic freaks like math like myself and in the US as well. When you look at a baseball scoreboard, you are overwhelmed by statistics, which you don't see in a football scoreboard which says Liverpool seven Manchester United nil for example.

John Bailer
You just just picked a random result.

Matt Dowsett
Which was the last Liverpool game I was at. Yeah. Oh, yeah. Oh, wow. But baseball and cricket lend themselves to statistics in a way that no other sports do. And so one of the ones that I've known about, and actually I've written up for Significance and have submitted it, is around another myth, which is the myth of the Nelson. And the myth of the Nelson is very interesting. So a Nelson score in cricket is one of 111 or subsequent multiples of 111, 222, 333. They are considered, according to the myth, to be unlucky in cricket, and therefore that you are more likely to lose a wicket when a Nelson comes around. So if a team or an individual is on a score of 111, it's considered unlucky until that Nelson score has passed until more rooms have been scored. And so I've been running a study based on that. And found it is a myth certainly for the lovers. But that's been one of the ones that I've been looking at. And quite an interesting one, because it's actually a very compact problem that is very easy to disprove. But the real cleverness of it is all the real trick in there is how to frame the question, because the question isn't simple. Because obviously, a score of 111 has to be reached later down the line. You don't just start on a score of 111, and 111 runs for an individual is actually a good score. So why would it be unlucky? So framing the question in there was probably more important than the stats themselves. So that's been quite an interesting one to do.

John Bailer
Yeah. So just as an FYI, our very first Stats and Stories episode was a baseball statistics episode. So if you know, the sabermetrics Society of American baseball research metrics was embedded in part of that conversation. You know, the one thing that I think about these myths, before we started the episode today, we were talking about the two goal lead as being the most dangerous lead. And the thing that's kind of interesting about that, whereas when you're talking about the Nelson, you're very much referring to a particular sport and in particular situation in that sport, you know, the two goal lead, you know, that could be thought of and whether it's hockey, you know, field hockey, or ice hockey, or it could be in football. So there are other sports where you might have seen this. So I'm just curious. I would really be interested in seeing how that plays out. But you'd really have to track the status of play in order to think about that as a isn't an analysis.

Matt Dowsett
Yes. And collecting the data, I think will be quite challenging, but it's an interesting one to explore.

John Bailer
One more, there's one question. I mean, Rosemary, you're gonna wrap us up. She always wants to cut me off. I mean, you know, Matt, come on, help me out here. Yeah. So the most important question is, what did your brother say?

Did he believe you? Did he say, go away? Pow. You know?

Matt Dowsett
Yes. He believed me. Of course, he understands that I'm a real fan of statistics. And I think he was probably more concerned with the final result of the Legion.

John Bailer
So he was convinced you convinced them all right.

Matt Dowsett
Yes, he was absolutely convinced.

Rosemary Pennington
Well, that's all the time we have for this episode of Stats and Stories. Matt, thank you so much for joining us today.

Matt Dowsett
You're very welcome. Thank you for having me.

Rosemary Pennington
Stats and Stories is a partnership between Miami University’s Departments of Statistics, and Media, Journalism and Film, and the American Statistical Association. You can follow us on Twitter, Apple podcasts, or other places you can find podcasts. If you’d like to share your thoughts on the program send your email to statsandstories@miamioh.edu or check us out at statsandstories.net, and be sure to listen for future editions of Stats and Stories, where we discuss the statistics behind the stories and the stories behind the statistics.