A new improved model of the degree of grey slope incidence based on the changing rate of slope

Based on studying all kinds of main degree of grey incidence models, it is founded that there are some flaws in those models. For example some models do not meet the property of normality, and can not reflect the relation of positive-negative between sequences and so on. In order to solve those problems, a new model for grey incidence based on the changing rate of slope is proposed. This model calculates the ratio of absolute value of incremental between a raw datum and its next one in one sequence. Then we can apply the ratio to calculate the degree of grey incidence between sequences. The new model is satisfied with not only the property of normality, but also the property of order preservation. At the same time, the result also can reflect the relation of positive-negative. The model is proved to be practical in both theories and applications.