Which soccer/association football statistic gives the most comprehensive assessment of a player in his or her position?

Question

There are defenders, midfielders, forwards and goalkeepers. If I want to compare non-keeper player to player, which statistic is the best?

In reply to answers below, if the synergy is important, is there a bundle or even a single statistic(s) to compare non-keeper player 1 to player 2 in the synergy of team A and synergy of team B. For example, (p1,sA) to (p2,sA) and (p1,sB) to (p2,sB). As we see there are two variables, are there statistical models to slot all four pairs of numbers and compare among themselves?

Answer 1

There isn't one, or at least you need to define "best" much more precisely.

To take a naive example: imagine you have four forwards. Two of them are excellent finishers and will score lots of goals if given opportunities, and two of them will create lots of opportunities for other players, but not score that many goals themselves. The best team will have have one of the finishers and one of the creators, and it is the synergy between the players which gives them a lot of their value.

Now of course, football is a much more complicated game than just "creators" and "finishers", and that makes the concept of a single statistic which can be used to compare players even less valid.