Quantifying computational effort required for stochastic averages

We propose a measure that quantifies the effort needed to compute a given stochastic average, considered in the context of molecular modeling. This "difficulty index" is defined in terms of CPU time, observed uncertainty, and a characteristic scale for the quantity being computed. This metric provides a focus for optimization and comparison of methods and, if applied broadly, could aid understanding of the impact of models, algorithms, implementations, and platforms on performance of molecular modeling techniques. (Graph Presented).