Always bear in mind that the numbers produced are from random samples, so you should be careful when interpreting their meaning. The rate of sampling is always coarse in comparison to the function call rate, so it is possible for strange effects to occur and significant events to be missed. For example, resonance may occur when an event always occurs between regular sampling times. In practice, however, this is not usually a problem.
LispWorks IDE User Guide (Unix version) - 25 Nov 2011