The transfer window slams shut on Friday evening at 11pm UK time. Between now and then managers around the world will be scouting players in all positions from every league as they try strengthening their teams whilst still getting the best possible bargain.

The issue facing the managers and scouts is that, generally speaking, they only get to see a player in detail once or twice and after that they compile a report from which decisions can be made. Those reports are vital and whilst there is nothing that can replace having a scout at a game running his eye over a specific player, it is extremely important to view the full range of data of that player. A similar issue faces international managers when trying to select players particularly in a World Cup year. Can they rely on the occasional game that they view when watching the many candidates in action? Will this allow them to see the true abilities of the player in question?

When it comes to scouting, TV doesn’t tell the whole story either. But how can managers and scouts swerve the problem of not being able to view a player in the flesh every week? The answer – statistical stability.

In order to explain this better, we have looked at Tottenham Hotspur winger, Aaron Lennon and his performances this season. His form is of particular importance to England manager Roy Hodgson now that Theo Walcott is out of the World Cup with Lennon being touted as a possible replacement. So, for example, if Hodgson viewed Lennon in the game against Swansea, he would have walked away thinking that the solution to Walcott’s absence would lie elsewhere as in this game Lennon’s number of good attacking actions was well below his own average. Looking at the individual player’s average over the course of the season assists in making a proper analysis of his ability and does away with incorrect decision making based on flash-in-the-pan performances by that player – from both sides of the spectrum.

He also created fewer chances during that game when compared to the rest of his games. Should Hodgson have observed Lennon in the game against Manchester United at White Hart Lane, he would have seen that Lennon, despite having fewer attacking actions per game, was well above his personal average of good attacking actions and might well have made a provisional booking for the Spurs winger.

Ultimately it is all about looking at stability throughout the course of the season. This allows a scout or international manager to make an informed decision. Using stats from one off game essentially sells both the player and the team short.

So how do we work out how stable a specific player is in terms of form and skill? Using Lennon again, we compiled all his attacking actions from the season thus far. Once we had all this information, we were able to plot out exactly how many actions he performs per game, what his average is and how many of those are good attacking actions. Combine these all together and we were able to create a stability graph. This can be seen below:

We also looked at the key actions that an attacking midfielder like Lennon is expected to complete during the course of a game. We defined those as the breaking of the first defensive line, the breaking of the second defensive line and finally how many chances he creates per game. Once again we were able to determine his league average as can been seen below:

What can be seen from the fluctuation in the above graphs is that if Lennon wants to be on the plane to Brazil in the summer, he needs to raise his game and bring a high level of consistency to his key attacking actions. A conclusion like this can only be seen when looking at Lennon’s stability graph as opposed to viewing random game performance data!

Photo Courtesy of:

www.flickr.com/photos/49514223@N04/4542566613/

