Monitoring user terminal applications using performance statistics for combinations of different reported characteristic dimensions and values

An application analysis computer receives reports from user terminals which contain application performance metrics and dimensions having values characterizing the applications and the user terminals. Statistics for each different one of the performance metrics across the reports are generated for repeating time intervals. One of the statistics that has changed between two of the time intervals by an amount that satisfies a defined rule is identified, and the associated performance metric is selected for analysis. For each combination of a different one of the dimensions and a different one of the values occurring for the dimension, a statistic is generated for the selected performance metric associated with the combination, and a counter is incremented that tracks a number of occurrences of the combination among the reports. Sets of the statistic and the counter for particular ones of the combinations that satisfy an action rule are identified.