1. A system comprising: one or more computers including program components executed by said one or more computers, which cause said one or more computers to perform the steps of: 1) receiving by said one or more computers, including a memory and a processor, a plurality of classified data records, each of said classified data records containing a first classification, a first set of one or more attributes, and a first set of one or more data values, each of said attributes associated with a corresponding one or more of said data values; 2) training a first classifier on said one or more computers using said plurality of classified data records to calculate a first model, and storing said first model on said one or more computers; 3) selecting with said one or more computers, a first subset of data records from said plurality of classified data records, said first subset containing at least one of said plurality of classified data records; 4) creating with said one or more computers, for each data record in said first subset, at least one corresponding testing data record; 5) classifying using said first classifier with said one or more computers, each of said at least one testing data records to create a testing classification associated with each of said corresponding testing data records; and 6) calculating, by said one or more computers, a score collectively representing sensitivity to change of each of said data records in said first subset, and storing said score on said one or more computers, further comprising calculating said score using the following formula: score = ∑ j = 1 n ⁢ ( w j ) n , ⁢ where ⁢ : ⁢ ⁢ w j = w j + + w j - 2 , w j + = d j + d ⁢ ⁢ and ⁢ ⁢ w j - = d j - d .