While initial-state ECR provides a measure of the likelihood of a favorable outcome , it does not address how well a particular state representation captures key decision points . That is , it does not directly represent the extent to which each deci-sion along the path to a successful outcome con-tributed to that outcome , or whether the second-best decision in a particular state would have been equally useful . In order to measure this dif-ference , we introduce the Separation Ratio ( SR ) , which represents how much better a particular policy is compared to its alternatives . SR for a state is calculated by taking the absolute differ-ence between the estimated values of two actions in that state and dividing by the mean of the two values .