On the distribution of runs scored and batting strategy in test cricket

摘要

Negative binomial distributions are fitted to partnership scores and innings scores in test cricket. For partnership scores, we use a parametric model that allows us to consider run rate as a covariate in the distribution of runs scored and hence to use run rate as a surrogate for batting strategy. Then we describe the implied influence of run rate on match outcome probabilities given the state of the match at some point during the third innings; we refer to such a point in the match as the current position. Match outcome probabilities are calculated by using a model for the outcome given the end of the third-innings position, and a model for transitions from the current position to the end of the third-innings position, with transition probabilities considered as a function of run rate. Although the run rate is not wholly in the control of the batting side, our approach at least allows a captain or team analyst to consider the match outcome probability if the team can bat towards a target at a particular run rate. This will then at least indicate whether an aggressive or defensive batting strategy is desirable.