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The world cup as seen through the lens of Twitter

Posted on July 16th, 2018   

The world cup is over. It’s been a thrilling month of exciting matches, great goals and surprises. Events like the world cup get discussed and mentioned a lot on Twitter. This allows us to determine which events sparked the most discussion, as well as establish which teams got the most positive response from the Twitterverse.

Let’s start by taking a look at the top moments of the World Cup. We measure this by looking at the moments that led to the most discussion on Twitter, so many will be heavily context dependent rather than noteworthy standalone moments. The top moments as far as the Twitter community was concerned were England getting knocked out of the World Cup, Cristiano Ronaldo’s hat trick against Spain and England finally winning a match on Penalties. Other key moments are shown below.

We can also use sentiment analysis to find out which teams impressed people the most and which teams people were less pleased with.

France, Belgium and England lead the way for teams that people responded the most positively to. Croatia were 7th in comparison. The teams that people responded most negatively to were Saudi Arabia, Colombia, Argentina, Egypt, Poland and Germany. Spain and Portugal also received relatively poor responses overall.

There’s not much left to say on the World Cup, except congratulations to France! Not only did they win the world cup, but they did so in a manner that impressed the Twitterverse!

World Cup Final and third place play-off forecasts

Posted on July 12th, 2018   

The World Cup semi-finals are over. France and Croatia have progressed to the finals of this year’s World Cup.

Below are our predictions for the World Cup final and third place play-offs:

 

 

 

A World Cup of late goals, penalties, own goals and unexpected results?

Posted on July 11th, 2018   

The 2018 World Cup is drawing to a close. It’s been a very interesting and dramatic tournament to follow.

There has been a lot of discussion on how this World Cup stands out in terms of the nature of the goals scored. In particular, there is a lot of discussion around the increased number of penalty goals, own goals and late goals in the game. This begs the question: Are there really more of these types of goals and how do the own goal, penalty and late goal rate compared to the Premier League?

The graph below shows the distribution of goal times in a game. This World Cup, 14.3% of all goals scored were scored after the 90th minute! To provide some context, in the Premier League, only 5.1% of all goals are scored after the 90th minute.

The table below compares the goal rate this World Cup as well as the number and proportion of penalties, own goals and late goals.

 

The overall number of goals per match this World Cup is slightly lower than the 2014 World Cup, and around 10% lower that the average number of goals in a Premier League match. The distribution of types of goals is quite different to the Premier League, however. 16% of all goals this World Cup have been penalties (compared to the 6.8% observed in the Premier League), 20.5% of all goals have been own goals (compared to the 3.5% seen in the Premier League) and as stated earlier, there are 2.8 times as many goals scored after the 90th minute as we observe in the Premier League.

Several people have also commented on the number of apparent surprising results. For example, Germany getting knocked out of the Group Stage, Russia beating Spain, Belgium beating Brazil, etc. Has this World Cup really had more surprising results than previous ones? The graph below compares how unpredictable the results of the competition have been.

The number of unexpected results in this World Cup has been in line with the levels observed in previous World Cups, but more surprising than the Premier League. The World Cup with the most surprising results in the recent past is 2010 and the World Cup with the least surprising results has been in 2006.

It looks like this really is a World Cup of late goals, own goals and penalties, but the number of own goals is particularly remarkable. It wouldn’t surprise us if England – Croatia match tonight ends up being won by a 90th+ minute own goal or penalty!

Should England lose to Belgium?

Posted on June 28th, 2018   

England are going into their third and final match against Belgium this evening as favourites to with the match (38% chance of winning), but should they win it?

 

There has been much discussion in the past couple of days on the potential benefits of England finishing second in group G to have an easier run of fixtures in the knock-out stages of the competition.

If England finish second in the group, they have a 7.7% chance of winning the World Cup compared to only a 6.2% chance if they finish first (the calculations were run before the last set of group H fixtures were played, so the teams that finished first and second in group H are not known at the time of writing). This is largely due to the likely event of having to face Brazil in the Quarter finals if they progress to the round of 16 as top of group G rather than Sweden or Switzerland if they finish second in the group.

The full list of likely opponents for each stage of the competition can be found below.

Regardless of the result tonight, England fans can take comfort in knowing that they are guaranteed to go through to the round of 16. It will be interesting to see if they choose to do that by giving it all they’ve got or prefer to game the system and maximise their chances of winning the world cup.

Social media response to the England vs Panama match

Posted on June 25th, 2018   

England’s second game against Panama played out considerably better than their opening game against Tunisia. The graphs below show how Twitter responded during the course of the match.

Social media activity was at its highest just after Harry Kane scored his second penalty to make the score 5-0 shortly before half time, but the most positive comments came just after the Jesse Lingard long range goal.

Despite the response to Harry Kane’s second penalty goal against Panama being the strongest response that match, it still doesn’t match the response to his late winner against Tunisia.

The Panama match as a whole is now the most talked about match on Twitter, followed closely by the Argentina vs Croatia match.

Other key moments in the world cup that elicited strong responses on Twitter are Argentina’s 3-0 loss to Croatia and Toni Kroos’ spectacular 95th minute goal against Sweden to win the match.

World cup progression forecasts after second round of group stage matches

Posted on June 25th, 2018   

With the World Cup firmly underway, each team only has one match left to play in the group stage.

Brazil and Germany have the greatest likelihood of winning their respective 3rd round matches, each with a 73% chance whilst Croatia, Argentina, Spain and Colombia also have a reasonably high chance of victory. Japan’s game against Poland may prove to be the most entertaining with an average of 3.1 goals scored expected, and the result may decide who England play in the round of 16.

A couple of the groups have already been decided in terms of who is going through. Uruguay and Russia will progress from Group A whilst England and Belgium will follow from Group G. However, whilst Croatia are almost guaranteed to finish top of their group, both Nigeria and Argentina have a chance of making it through (Argentina’s chances are just over 50%).

As many people may guess anyway, Brazil are still the most likely winners of the whole tournament, with a 30.6% chance. However, this number is not particularly high, meaning that even though they’re the favourites to win the competition, it’s still more likely for them to not win it than for them to win it. Spain are the second most likely team to win it with a 16% chance.

Despite England’s 6 goals scored against Panama, they still rank only seventh in strength of attack. However, the fact that they have the third strongest defence makes them the fourth most likely team to win the tournament

Tunisia – England as seen through social media

Posted on June 19th, 2018   

Social media platforms such as Twitter are a common outlet for discussion about the World Cup. The patterns and nature of the social media content can tell us a lot about how people respond to different teams and events in the World Cup.

The number mentions of “#WorldCup” spike every time an interesting event occurs at the World cup. The size of the peaks provide an indication of the events that most sparked discussion on Twitter. Harry Kane’s winning goal from last night is the 5th most discussed World Cup event on Twitter, after 3 goals from the Portugal vs Spain match and the final whistle sealing Germany’s loss in their opening game against Mexico.

We can home in on how Twitter responded to the England Tunisia game. The graph below shows how the twitter activity volumes of tweets mentioning the England and Tunisia evolved through the course of last night’s game.

England was mentioned most often immediately following the Harry Kane goals, with his second goal eliciting a stronger response than the first. Similarly Tunisia mentions were highest immediately following their goal. The responses to non-goal events such as Sterling and Lingard’s missed opportunities can also be seen in the graph.

Sentiment analysis on these tweets reveals that England fans were getting increasingly unhappy with the team over the course of the game until Harry Kane’s late winner brought comment sentiment polarity back up to a level slightly higher than pre-match levels.

Overall, the England vs Tunisia game was the third most discussed match of the World Cup. It will be interesting to see how Twitter will respond to England’s other group stage fixtures.

England’s prospects for the World Cup

Posted on June 18th, 2018   

Tonight is England’s first match in the 2018 World Cup. England are heading into it as strong favourites to win the match, but the past couple of days have seen several competition favourites fail to win their opening matches. These events serve as a good reminder that being a stronger team is far from a guarantee of victory in a match, particularly over 90 minutes of football. England’s chance of winning tonight is just over 59%, with a 27% chance of a draw and a 14% chance of Tunisia winning.

Their overall group prospects are fairly good. They have a 43% chance of finishing first, 37% of finishing second and only a 20% chance of getting knocked out. 

England’s chances of making it to the final are 11.7%, with a 5.2% chance of winning the competition. This means that there is a higher chance of England not making it past the group stage than there is of England making it to the World Cup final.

Interestingly, the England team is currently the most defensive we’ve seen in over a decade. England’s defence has been steadily improving over the past 7 years, while their attack has been declining. They are currently the 3rd best team in defence, but only 11th best team in attack. This makes them the 5th best team overall.

Their overall chance of winning the competition this year is higher than it was last World Cup, but it’s not as high as it was for the 2006 or 2010 World Cups. Having said that, England’s previous teams were certainly underachievers relative to their team strength. Let’s see if this squad can live up to their potential.

 

 

World Cup buzz on Twitter

Posted on June 15th, 2018   

The world cup has begun, and social media has been buzzing with excitement over it.

Below are the most talked about teams across the course of the past week (before yesterday’s World Cup opening match between Russia and Saudi Arabia).

Spain are the most talked about team, in large part due to their manager, Julen Lopetegui, being sacked a day before the World Cup started. Interestingly, the top 10 most talked about teams contain the 8 most likely teams to win the world cup according to the bookies (the two teams that aren’t likely to win the World Cup, but are still mentioned a lot are Russia, who are hosts, and Mexico). This suggests that there is some degree of correlation between team strength and social media mentions.  With this in mind, it’s worth pointing out that England’s social media mentions are disproportionately high compared to their chances of winning the world cup. The cup is probably not “coming home” (there is a 5% chance of England winning it). Someone needs to let the England fans know.

How many points for CL qualification?

Posted on April 9th, 2018   

One of the perennial discussions we hear near the end of the Premier League season is “What is the point threshold that guarantees a team is safe from relegation”. Right now, as we already know two of the three teams to compete in the Championship next year (well, ok, Middlesbrough still have a mathematical chance), it is the battle for a CL spot that is way more interesting. Chelsea is assured a top four spot as practically are Spurs (97.5% chance even if they lose all remaining matches), leaving two places for the challengers Liverpool, Man City, Man United, and Arsenal.

Before we go on to answer the question “How many points secure a CL spot”, we need to make clear that, theoretically, the answer is different after every match day is played. In a more balanced season, where teams closer to the top lose often to teams lower, we expect a lower threshold. In a season where five or six teams win more often, the point threshold for CL qualification is expected to be higher. That is, if at the beginning of a season we can make the statement “70 points send you to next season’s CL with 70% probability” it doesn’t mean that the same is true after half of the matches are already played.

First of all we take a look at the number of points of the top four teams since 95/96 (first PL season with 20 participants).

We see that there is an upwards trend in the points of the top four teams over time. This suggests that the gap between stronger and weaker teams is growing. In order to have a more rigorous analysis we should take this trend into account.

Now to the main question: What is the probability of qualifying for the CL for a given amount of points earned?

We will use two different methods to estimate the probabilities in question. The first is based on the final tables of the past 21 PL seasons. We don’t want to go deep into technical details, but just briefly, for a given amount of points X, we look at how often a team with X points made it into the top four. If there is more than one team with X points and not all of those teams either succeeded or failed, we count the season as partially successful (for an X-point team). If there are no teams with X points, we look at where an X-point team would have finished in the final table. Here’s what we get.

So, it looks like, based on the past, with 66 points a team has about 48% chance to qualify for next season’s CL. If we take into account the trend seen in the first plot, we tend to believe that the chances are at most that much. 79 points almost certainly guarantee a CL spot. But even with as little as 61 points there seems to be a realistic chance (17%).

The other method to tackle this, the parametric method, is based on simulating PL seasons using a model which associates different strengths to different teams.  The way to do this is to take the team strengths and, allowing for some fluctuation of them along the season, simulate full PL seasons of matches. Then we can treat the simulated seasons like we treated the past seasons in the previous method and estimate the conditional probabilities in question. This second method has some advantages and some disadvantages: One of the disadvantages is that it is parametric, i.e. it assumes that the PL match results are generated according the underlying model. This is always an assumption in statistics and it can deviate from the truth. A big advantage is that it allows us to simulate only a part of the season, i.e. we can take the PL table as it stands right now and simulate only the remaining matches. Additionally it allows us to avoid the trend problem of the other approach, if the team strength estimates are current.  In the chart below you can see what were the CL qualification chances (given points earned at the end of season) before the season started, and what these chances are now (again, given points earned at the end of the season).

First of all we see that the CL qualification chances at the start of the season (blue line) look a bit different in this plot compared to the previous one. One of the main reasons that drives the differences is that the previous plot is a blend of the sets of team strengths at the start of the previous 20 seasons, whereas the last plot is based solely on the strengths of the 20 teams of the current PL season. Interesting is also the difference between the blue and red lines in the plot above. As the current season is nearly over, there is a much smaller range of final points that can take a team to next season’s CL, compared to the situation at the start of the season.  We also learn that this season the bar is higher than we would have expected.  At the start of the season 70 points would have got you more than a 50% chance of CL qualification.  Now, 70 points only has a 5% chance of being enough.

So, how many points do you need to make it to the CL?  It depends when you ask.  At this moment 73 points gets you a 51% chance, and 76 points a more than 95% chance.

 
© Decision Technology 2018