1. A computer-based method of classifying a test instance in accordance with a data set, the method comprising the steps of: obtaining a test instance; presenting to the user at least one projection representing a distribution of the data set; the user isolating a portion of the data presented in the at least one projection based on a relationship between the test instance and the data presented in the at least one projection; determining a behavior of the isolated portion of data; and determining a class for the test instance based on the isolated portion of data when the user makes a decision to do so based on the determined behavior of the isolated portion of data.