A NLR—METHOD OF FITTING CoSINE MODEL AND ITS PEAK—DAY ESTIMATE FOR IHE INCIDENCE OF INFECTIOUS DISEASES

The datafromDISEASE SURVEILLANCE1996；11(6)：228were reanalyzed by the authors in this paper The cosine(COS)model and circular distribution(CD)model were used for fitting the equations and estimating the peakday．The former method could abso obtained the expected values.Because the two models were not so easy to be fitted．a simple procedure of NLRmethod from SPSS/PC+4.0 package Was written by the authors to calculate the needed parameters，the peakday and the expected values of COSmode；A better equation of COSmodel which was equivalent to cDmodel WS suggested