Viewpoint representation validation: a case study on two metrics from the Chidamber and Kemerer suite
Abstract A metric definition follows from a comprehensive sequence of steps that takes into account all the requirements of the representational theory of measurement. The last step emphasises that numerical relations must preserve and are preserved by empirical relations or viewpoints. It is the preservation of viewpoints in numerical relations that we have tried to empirically validate for the metrics depth of inheritance tree (DIT) and number of children (NOC), proposed by Chidamber and Kemerer [S.R. Chidamber, C.F. Kemerer, IEEE Trans. Software Eng. 20 (6) (1994) 476–493], and which we also refer to as viewpoint representation validation. An analysis of the results indicates the possibility of the two metrics not preserving the viewpoints adequately.