A system, method, and program product for interpreting, optimizing, and customizing data mining models through the use of statistical techniques that utilize diagnostic measures and statistical significance testing. A data processing system is disclosed that includes a data mining system for mining data from a data warehouse in accordance with a data model, wherein the data model defines how data groups can be partitioned; and a data group analysis system that calculates a set of diagnostic measures and performs statistical significance tests for a defined data group.