Usually, Dynamic works well. The dynamic strategy precisely models the probability of missing for a given predictor variable and estimates the probability of a missing value given the values of other predictors. For example, with the dynamic strategy, the analysis can assign a higher probability of a missing value to X1 when X2 is greater than 10. The heuristic strategy does not model the probability of a missing value. Consider the heuristic strategy when the data have missing values and the analysis takes too long to find a satistfactory solution.