The model of grey periodic incidence and their rehabilitation based on the slope

Grey incidence model determines the closeness degree from the closeness and similarity of statistical sequence's geometrical form. Traditional grey incidence model calculates statistical sequence's correlation degree from the perspectives of its acreage, slope, changing velocity, etc. These incidence models have dual influences exerted by horizontal and vertical coordinates. Subsequently, inference of other factors occurs when we analyze the relationship between statistical sequence's individual factors. To overcome this defect, the author puts forward the periodic correlation model based on slope and draws the conclusion that the model is in reference to the fluctuation period and direction of the wave, but is independent of its swing, and that it can show the positive-negative relevance. The results show that this model is an effective one in some examples.