Measuring the effectiveness of playing strategies at soccer

Using a notational system which records on-the-ball events taking place throughout a soccer match, the game can be broken down into a series of team possessions. To assess the effectiveness of a team possession, a quantitative variable is developed representing the probability of a goal being scored, minus the probability of one being conceded. This variable, called the yield, can be used to evaluate both the expected outcome of a team possession originating in a given situation, as well as the actual outcome of the possession. In this way, the effectiveness of different strategies occurring during the possession can be quantified and compared.