For the metric for model validation, the confidence interval of the validation metric is presented by calculating the infimum and supremum of the distance between the empirical probability distribution of model response and the confidence interval of the experimental distribution. Besides, a multiple response validation metric based on the distance of probability distribution is proposed with its confidence interval by constructing experimental covariance matrix. The metric makes use of the whole data distribution and considers the correlation among multiple model responses. Simulation results show that the validation error rate of the proposed metric is lower than other two metrics.