1. A computerized system for developing a data model in a data mining system, comprising: a processor and a memory, the memory includes; a database table of user predefined data transformations, at least one of the data transformations in the database table being reused by a plurality of data models; a data import system for extracting raw data from a data warehouse; a variable determination system for determining a set of variables for a desired prediction, wherein the set of variables comprises at least one predefined data transformation selected from the database table, wherein the database table of predefined data transformations associates each of the predefined data transformations with a unique identifier, a description and a validity period, and wherein the variable determination system retrieves the at least one predefined data transformation from the database table according to its unique identifier; a model development system for developing a data model for the desired prediction using the determined variables; and a specification development system for developing a specification for applying the data model operationally; wherein the model development system applies the raw data to the set of variables and derives a mathematical relationship between the set of variables.