What’s hard in soccer is that, from statistics alone, you can not determine if a pass was of positive value. Hell, even a successful pass might not have a positive value; for example, let say that a left-back makes a 30-yard pass to his left-winger and that the same left-winger kicks it back to his own keeper. That’s two completed passes but yet, you are behind your starting position. Trying to put a value on that, let’s say that the left-back’s pass cleared 2 opposing players, making it a +2 value but the left-winger’s pass got those 2 opposing players behind the ball again. That would make that completed pass a -2.

Now let’s pretend that the left-back’s pass was a superb pass to the left-winger but because he misplayed it, it went to the other team. Should the left-back be penalized because of that? It’s comparable to gridiron football, when a quarterback puts the football in the hands of his receiver and drops it. If you want to evaluate those kind of passes, the outcome (completed or incomplete) is irrelevant. Making a parallel to the book Moneyball, If a ball is hit at a certain velocity, trajectory and space where it ends as a base hit 98% of the time but on that one occasion, the centerfielder robs the hitter, it doesn’t matter; it was a good hit. (Just found the reference in the book; “From the ten years worth of data, you can see that there have been 8,642 practically identical hits. You can see that 92 percent of the time the hit went for a double, 4 percent for a single, and 4 percent it was caught. Suppose the average value of that event is .50 of a run. No matter what actually happened, the system credits the hitter with having generated .50 of a run”). So basically, the outcome doesn’t affect quality.

If I stick with the book and Billy Beane for a moment, probably the questions Beane would have asked himself are “Is it better getting a star defensive player to prevent shots on getting on net or is it better having a star keeper keeping the shots out?” or “Is it worth having wingers do crosses?”. For the last question, are your chances better to score when you cross the ball when you’re in deep or is it better to play short passes and try to get in a scoring position? This actually could be calculated, don’t know if it ever was. Another question Beane would have asked himself is “On a goal kick, is it better to play it short or punt upfield?”

Anyway, I’ll leave it at that for now… I have too many questions myself about how to do this

Is this thing on?