A representation is a surrogate for reality. The surrogate can be physical or abstract. Physical representations are miniature models of reality, such as a physical 3D model of an amusement park. Physical representations are instrumental in learning about and understanding reality. They provide observers with an overview and enable manipulation of reality [Page 369]that otherwise could not be perceived directly and comprehended holistically. Likewise, abstract representations capture the essence of reality to facilitate analysis, modeling, and understanding. Statistical models summarize parameters and highlight significant characteristics to allow observers to grasp an otherwise seemingly chaotic reality. Mathematical models, for example, are numerical and computational representations to generalize and predict reality. Data models represent reality by formalizing data elements and their relationships. Furthermore, knowledge representation schemes extract ...