Grey system forecast of cotton yield and calamity year in Henan province

By using the theory and method of the dynamic establishing model of grey system, the forecast models of Henan province^s cotton yield and calamity year were established. The yield forecast model indicates that the cotton yield in Henan will reach 810 kg/ha by 1995, and 960 kg/ha by the end of 2000. The calamity year model reveals that the first, second and third calamity year after 1988 will be 1992, 1996 and 2006, respectively. The forecast provides scientific basis for making policies and adopting appropriate measures to guide Henan^s Cotten production.