1. A method for altering one or more parameters of a measurement system, comprising: analyzing a sample using the system to generate values from classification channels of the system for a population of particles in the sample; identifying a region in a classification space in which the values for the population are located; and determining an optimized classification region for the population using one or more properties of the values of the population, wherein the optimized classification region contains a predetermined and fixed percentage of the values for the population, and wherein the optimized classification region is used for classification of particles in additional samples.