Tuesday 29 September 2015

Which of Europe's Best Scorers Are On Fire, Really?: A Multi-Measure Analysis

With the new football season now well underway, some of Europe’s top strikers have already found their best form while others struggle to regain it. Considering performances in Europe’s five major domestic leagues (Premier League, La Liga, Bundesliga, Serie A and Ligue 1) as well as its main international team competitions (UEFA Champions and Europa Leagues) the “happy few” scorers with already six or more goals to their tally, as of 29/09/15 (morning), are as follows:

Tabel 1. Simple ranking: Europe's top scorers by number of goals scored 

In my May’s post, “Which Premier League Top Scorer Would You Like in Your Team?,” I proposed an evaluation method for top scorers based on multiple measures that would allow for deeper insight into what lies beyond a simple ranking. In this post, I will evaluate Europe’s current top scorers by means of this method. A multi-measure analysis will bear out several critical insights and nuances about Europe’s on-fire scorers.

·      “Efficacy”, or the number of penalty-adjusted goals scored:

For reasons explained in the May post, I adjust the ranking so that converted penalties account for half a field goal. Those with an efficacy rating higher than five are as follows:

Tabel 2. Efficacy ranking: Converted penalties count for half a (field) goal

Observation 1: Making the recommended adjustment for penalties converted, the difference between Lewandowski’s ten goals and first contenders Aubameyang, Müller and Cristiano Ronaldo (all having converted three penalties) becomes clearer. Indeed, Lewandowski so far managed to score as many field goals as both Müller and Ronaldo together.

Observation 2: The penalty adjustment also allows for a better appreciation of the difference between Real Madrid teammates Cristiano Ronaldo’s eight and Benzema’s six goals: If Benítez appointed Benzema rather than Ronaldo as penalty taker, Benzema would have overtaken Ronaldo as the club’s top scorer as Ronaldo would then have scored max. five and Benzema min. six times.

·      “Efficiency”, or the average number of penalty-adjusted goals scored per 90 minutes on the pitch:

The rationale behind the efficiency measure, I explained in the May post. Efficiency, which reflects a scorer’s average performance during a ninety-minute (i.e full-game) period, is all the more relevant when comparing across leagues: not all leagues have the same number of match days and some teams additionally compete in Europe whereas others don’t.

Five of Europe’s top scorers so far have managed to score on average one or more goals during every ninety minutes on the pitch:

Tabel 3. Efficiency ranking: Avg. number of penalty-adjusted goals scored during 90 minutes

Observation 3: To put Lewandowski’s exceptional form in context, not only is he the only one who managed to almost put two field goals in per ninety minutes, but also has he been well over three times as efficient as Manchester United’s sensational signing Anthony Martial (efficiency: 0.54; including three games at Monaco) so far has been this season, for example.

Source: sueddeutsche.de

Observation 4: Karim Benzema so far has also been extraordinarily efficient, scoring more than twice as much as Martial, when on the field, as well comfortably outperforming his teammate Cristiano Ronaldo (efficiency: 0.93).

·      “Relative efficacy”, or the percentage of penalty-adjusted goals scored relative to the team:

As explained in the May post, relative efficacy accounts for the fact that it may well be more complicated to put goals in if you’re a forward at, say, Watford rather than Bayern Munich or Real Madrid.

Tabel 4. Relative efficacy ranking: Percentage of team's penalty-adjusted goals scored by top scorer

Observation 5: Note that the relatively most efficacious scorer in Europe, Watford’s Odion Ighalo, did not even show up in the simple goal top scorer ranking. In fact, none of these scorers featured in any of the above rankings and it is noteworthy that they play their football at relatively smaller teams, which partly accounts for why they managed to score half or more of their team’s (penalty-adjusted) goals.

Observation 6: It is important to note I only consider actual top scorers for these rankings, e.g. only one Premier League player scored more goals than Bournemouth’s Callum Wilson. Málaga, for instance, have not managed to score a single goal yet, so whoever will score their first will attain a 100% relative efficacy (i.e. will have scored 100% of the team’s goals at that point) – but he wouldn’t be anywhere near a league top scorer and thus should and would not enter in this ranking. A similar argument applies to the above efficiency ranking.

·      “Importance”, or the average of the virtual and eventual incremental points won by the player’s team because of a player's goals:

The notion of the importance of a goal in terms of additional points won for the team is critical and is also further detailed in the May post. Arguably, from a team perspective, it is the single most relevant measure as the team's objective is to maximize points rather than goals. Those top scorers whose goals already earned their team more than five points are:

Tabel 5. Importance ranking: Avg. of virtual and eventual incremental points won by team because of top scorer's goals

Observation 7: Lewandowski and Benzema have not only been putting in lots of goals, but also goals that led their respective teams to win more points, notably as opposed to Cristiano Ronaldo whose eight goals so far amounted to a total one-point importance only, according to the measure’s definition.

Observation 8: Ighalo’s ranking as Europe’s joint second team scorer in terms of most important goals for his club demonstrates that his topping the relative efficacy ranking is not just an oddity, but rather demonstrative of something highly meaningful.

Source: theguardian.com

Concluding observations from the multi-measure analysis:

Observation 9: Robert Lewandowski is clearly on fire: not only is he currently Europe’s most effective as well as efficient scorer, but also is he the scorer whose goals so far delivered most points to his team.

Observation 10: Some scorers who so far have been instrumental to their team’s successes, e.g. Griezmann and Ighalo, in a simple ranking of goals scored, would remain largely unnoticed, whereas the impact of others' goals, e.g. Cristiano Ronaldo's, may be overstated.

Observation 11: It is not any single measure, but the combination of several which results in a much deeper and nuanced insight into the meaning of the game’s top scorers.