English Premiership – Predicting Future Performance
With the AVIVA Premiership now having kicked off it will be interesting to see how it is progressing compared to pre-season expectations.
Often when looking how a season will play out the form from the previous season comes into the equation. While it is reflective of where a team is at in a period of time it is still only a very small part of a larger puzzle. Another assumption typically made to assess prospective performance is how well a team has recruited, and by “well” I mean the perceived quality of talent brought into the team.
To quote a recent article by Alex Shaw in RugbyPlanet;
“Newcastle were pre-season relegation favourites for many, especially following a summer of recruitment that saw them miss out on big-name signings to other Premiership clubs.”
Here is where there is disconnect between what is assumed that talent brings to a team and what the actual impact of bringing new talent in. Here is the thing; there is a fundamental misunderstanding of how teams work and that talent is not the biggest driver of success.
The article goes onto say;
“Dean Richards is a savvy operator, however, and after two wins and an agonisingly close loss to Leicester Tigers, Newcastle look like anything but relegation battlers at this point."
From my point of view this is indicative of that misunderstanding of how teams work as the writer now needs to explain why Newcastle is performing better then expected, and he uses the very ambiguous non-descript explanation of Dean Richards being a “savvy operator” – why?, because he can’t explain why Newcastle are performing the way they are. This is in no way having a go at the journalist. He is just like 98% of the world in his assumption of how teams work.
To truly understand how a team will perform you need to take a long-term view. This is what we do at my company GAIN LINE Analytics. The metrics that we have developed to measure team Cohesion give a different perspective on how teams work and how to determine the prospective success of a team.
When I talk about Cohesion I mean the measure of interrelationships between teammates. We use an algorithm that calculates multiples levels of Cohesion within a team using variables such as a player tenure and position. Cohesion, or TWI® as we call it, has a very strong linear correlation to performance and can impact performance as much as 40%. The higher the TWI® the higher the performance of the team, and visa-versa. The great strength of TWI® is that it is objective data that is calculated from the team squad giving metrics that are available at the beginning of the season. This means there is an understanding of how a team will perform prior to the first kick off.
At it’s highest level TWI® is very much driven by the club overall philosophy from the top down e.g. is the club a building club or a buying club. There is another significant factor that needs to be considered when looking at teams, and that is Salary. While the Premiership has a salary cap there is variation in overall salaries due to either limited resources or a capacity to maximize expenditure as well as the 2 player exception rule. Just like in the Premier League, the more salary a club has the more potential for higher skilled players. When considering both cohesion and salary (salary acts as a proxy for skill) a team’s Performance Capacity can be understood; to put it simply; Skill X Cohesion = Performance Capacity. Buy enough highly skilled players and you can mitigate low cohesion, or conversely build high cohesion and be successful without having to go to the market place for the highly skilled expensive players. Both of these methods can bring success but we have found that in the long run they generally give different outcomes. GAIN LINE Analytics has looked at 9 different sports over 30 years and the impact on performance of how teams are build remains constant. Teams that go down the “buying” philosophy require significant expenditure to remain successful but are generally volatile within and across seasons. If you have enough money you can buy a title but maintaining consistent success is very difficult. Teams that “build” gradually become more successful over time and do it in a way that is sustainable both on and off the pitch.
There is a third type of team that has the best of both worlds. A team that has moved from a “buy” philosophy to a “build" philosophy maintaining the ability to maximize expenditure. The advantage this team has is that not only can it bring in a top end player when needed but it also has the ability hold onto it’s younger players coming through the system – not having to worry about a “rich” club coming in to take the up and coming stars. These clubs have a building base, which makes them sustainable but can top up with quality players if and when required. High cohesion teams have the ability to integrate these top up player more easily than low cohesion teams so the negative aspects of “buying” is mitigated.
These different philosophies impact on how Cohesion is created and maintained within a team across multiple layers. We track a teams Cohesion across these multiple layers which gives the ability to look at prospective performance in the long term, within a season and game-by-game.
To give some perspective on the impact of Cohesion on performance. The trend graph below is a comparison of the defensive ranking of a Tier 1 Professional Rugby Union Team over a 16-year period. The higher the green graph points the better that seasons defensive performance. Also shown on the graph in the teams TWI® for each season in red. In each corresponding year the TWI® measure was determined prior to the season starting and the defensive rank was determined at the end of the season.
In the Rugby codes Cohesion manifests itself strongly in defense. This can be seen clearly in the graph. As TWI® changes, defensive performance changes accordingly. The Correlation Coefficient between seasonal change of Defensive Ranking and TWI® is 0.78 – this means that statistically TWI® can explain 61% of variation on field over the 16 seasons. Considering that the other 39% is home/away, injury, referee, weather etc, this makes the impact of Cohesion very significant. TWI also tracks very closely to the significant performance indicators like Win%.
To put this in perspective.
Q: What is the biggest factor in winning game?
A: Scoring more points than the opposition.
The ability to score more points than the opposition in pretty black and white when is come to impacting Win%. For the same team mentioned above the correlation of Win% over the 15 seasons to Points Different (Points For minus Points Against) is 0.90 – which means Points Difference can explain 81% of variance of Win%.
To further enhance the point;
The correlation of Win% to Points For is 0.64
The correlation of Win% to TWI® is 0.65
What this is saying is that TWI is as important as a teams ability to score points when it comes to Win%.
What this exercise does is show the magnitude of impact Cohesion has on team performance. It isn’t just an extra 1%er that you might get out of enhance S&C but a significant driver in overall performance that up to now has not been very well understood.
Next time we will look at how the Premiership will play-out based on the Cohesion driven performance.