In the summer of 2018, the national lacrosse teams of 46 countries from all across the globe travelled to Israel to battle it out to named the best team in the world.
Over the course of the tournament, there were 170 games with a total of 6,366 shots taken, of which 3,287 resulted in goals. 7,142 ground ball situations were contested, 3,701 Faceoffs taken and 1,595 minutes spent on the penalty bench. The result was that the USA were crowned champions for the 10th time after defeating Canada 9-8 in the final.
All data has been taken from the publicly available information on worldlacrosse2018.com, whose website seems to be no longer operational. Many thanks to them for gathering such high-quality data that makes the subsequent analysis in this blog possible.
Unsurprisingly, the USA came out on top in almost every category. They scored the most goals, won the highest proportion of faceoffs and ground balls and spent fewer minutes on the penalty bench than most teams. This is in addition to the fact that every game but one that the USA played was against teams who finished in the top 5 in the tournament, making their statistics all the more impressive. Statistically, if nothing else, the USA were the best team at the championships.
On the flip-side, the statistics will be tough reading for anybody from Uganda. Uganda were consistently at the wrong end of every chart, scoring among the fewest goals, winning fewest faceoffs and having the most penalties of any team in the tournament. This was however their first major international tournament, and their participation should be celebrated as they were the only African nation competing at the World Cup. This meant that teams from 6 continents* were represented at the championships, showing the growing popularity of the sport worldwide.
* Just waiting for Antartica to submit a team now...
Some of the observations that I personally found more surprising:
There is an old saying in Lacrosse that "ground balls win games". For those unfamiliar with the sport, a ground ball refers to a point in the game where neither team is in posession of the ball. This can be due to a number of reasons - perhaps a misplaced pass, or a defending player successfully knocking the ball out of the stick of an attacking player.
With the granularity of data provided, we can test this theory. For every game, the total number of ground-balls won by each team can be compared to the final score. The values have been converted to percentages to make them comparable between each game and each team.
Note that on the below chart, any dot in the top half of the chart represents a team that scored more than 50% of the goals scored in that game i.e. the team that won that game. No game ended with a goals percentage of 50% because every game was played until there was a winner.
It is immediately clear that there is a positive correlation between winning ground balls and winning games. The actual correlation value is 64%, which is very high for a real-world dataset in scenarios as complex as live sporting events. The p-value works out as a tiny fraction, indicating that these results are statistically significant. There is only a fraction-of-a-percent chance that winning more ground balls does not generally result in scoring more goals (i.e. there is a relationship!).
So - it seems to be that there is truth in the old saying. Ground balls do win games.
Since we also have the data available, let's look at Faceoffs too. For those unfamiliar with the sport, a Faceoff is taken to start every quarter of a game, and is also taken after every goal is scored. It's similar to a faceoff in ice hockey, or a throw-in in basketball. Both teams contest a 50:50 position, and the winner ends up with possession of the ball, from which their team can start an attack. Facing off is a highly specialised skill that typically only 2-3 players on any team will specialise in. Some teams even train a single player whose sole responsibility is to win face-offs and will then substitute themselves off the pitch.
Being good at faceoffs can mean an extra 10 possessions per game, in which time you are more likely to score and unlikely to concede. Therefore, we would expect to see a positive correlation between winning faceoffs and winning games. Repeating the analysis we did before for ground balls, we can create the following chart:
The correlation is there, but there is significantly more scatter. Some teams won 90%+ of face-offs but still ended up losing the game. The correlation value is 37%, however the p-value is still a tiny fraction, indicating that the relationship between winning face-offs and winning games is real but it is not the strongest predictor available of a game's winner.
The final attribute that can be assessed - does getting a lot of penalties significantly reduce the chances of your team winning?
Answer: no. The correlation is -5%, which is close to negligible. The correlation is negative, as would be expected (more penalties = less chance of winning) but the p-value is 35%. In statistics, a p-value of less than 5% is usually required to determine significance. Therefore, we conclude that the relationship is not significant, and even if it was, the effect is very small anyway.
So - while it may seem counter-intuitive, the statistics seem to show that spending time on penalties doesn't have a significant impact on your chances. However, I cannot advise this as an excuse to start making late hits...
Going back to a point made earlier, this could explain why Jamaica ended up finishing 13th. Without being rude, I wouldn't personally have expected Jamaica to finish in such a high position. The stats seem to suggest that Jamaica won a high proportion of ground balls, but also gave away a lot of penalties. Combining these two effects, the positive effects of winning ground balls and the negligible effects of conceding penalties, the result was that they had a very successful World Cup campaign.
Finally - because it was available, I have crunched the numbers for all players for all teams for the available statistics.