Research on the multiple and parallel properties of several grey relational models

Grey relational degree is the synthetic measure about the similarity of developing trend and the closing of the amount between two series. As an important part of the grey systems theory, grey relational analysis is the basis of the grey clustering analysis, grey decision-making and grey controlling. In this paper, we commented on several kinds of grey relational models. We studied the uniform and parallel properties of these grey relational models theoretically. We pointed out that some models satisfied to the uniform and parallel properties and others didn´t. It is indicated that seldom model could satisfy this two properties in common. Therefore, it is meaningful to make the grey relation theory perfect and to construct new grey relational models.