I’ve been bitching and moaning about data and how it’s used all week. So when a long term Grover sends in an e-mail and shows you how you can take minimal data and paint a very interesting story… well, you have to put it up!
Big thanks to Rhys Jagger for sending this over!
Arsenal do best when they don’t have so much of the ball in 2014/15
Here’s the analysis in a spreadsheet.
Data culled from BBC match reports (blame them if the stats are duff!) – I simply collected the following:
2. Shots on target
3. % possession
4. Goals Scored
As it turns out, there are 21 home and 21 away games to date, so I sorted the data using two passes:
1. First into Home and Away (Away at the top as A is before H).
2. Then by Arsenal possession % from the highest to the lowest.
Then I compared the data for the top 10 possession games vs the bottom 11 possession games both home and away and looked at what that told you.
1. Average shots per game for each of the four groups.
2. Average % possession for each of the four groups.
3. Average Goals/game for each group.
4. Average Points/Game for each group.
5. Average % of possession per shot on target.
6. Average goals Scored/Shot on Target for each group.
7. Average Pts/game/Shot on Target for each group.
1. There is no benefit to Arsenal, either home or away, in hogging possession in terms of winning games. A slight benefit away from home is counteracted by an astonishing disadvantage at home.
2. In fact, at home, Arsenal are almost guaranteed to win if they let their opponents have parity of possession. 31pts from 33 were accrued when Arsenal enjoyed an average of 50% possession, whereas only 15 pts from 30 were accrued with an average of nearly 65%.
3. However, there is a pretty good correlation, home and away, between points accrued per shot on target. Broadly, it is about 3 shots on target for every point gained.
4. However, within both the home games and the away games, it is clear that Shots on Target count far more when possession is not so plentiful.This is much more obvious at home and is probably related to Arsenal being profligate in front of goal if they have lots of possession, probably due to subconsciously feeling that each shot is less valuable. If that mindset could be altered to that of the games away from home when possession is scarce, Arsenal now might be ‘toppa the league…..’
5. It is also the case that Arsenal need more possession time away from home to achieve a shot on target (9.3% at home vs 11.7% away), however such data is probably skewed by the few big wins at home vs the very rare big wins away.
6. The most striking stat is the conversion rate of Shots on Target into Goals at the Emirates, but not, for whatever reason, away from home. When Arsenal have less possession at home, they convert almost one in two shots on target. When they have plenty of the ball, it is between one in four and one in five.
7. When you look closer at games where the least SOT were achieved, you see a long list of ‘top sides’: Spurs, Liverpool, Man City, Chelsea and Borussia Dortmund (twice) all showed 3 or less SOT/game. Arsenal achieved 2 wins, one draw and three losses from those games. Of the top teams, only Man Utd (twice) and Southampton let Arsenal create lots of chances to shoot on target.
I’m sure someone who has access to the stats can start drawing up stats for players based on:
1. Shots on target:total number of shots.
2. Goals score:shots on target.
That of course favours goal poachers inside the 6 yard box.
This data, however, unique to Arsenal and based solely on one season, does however say that shots on target is a good surrogate for goals scored and points gained, however it appears that ‘starving men are keener to kill game than fatsoes’……