Takizawa T, Ito T
Natl Inst Anim Health Q (Tokyo). 1977 Winter;17(4):179-83.
Supposing two mathematical models, additive and multiplicative, the authors estimated the secular trends of annual morbidities (1949 approximately 1975) of twelve infectious diseases of domestic animals. For each diseases ten different trend curves were fitted. It was found that five regression equations, namely, those for bovine trichomoniasis, bovine tuberculosis, equine infectious anemia, pullorum disease in chickens, and foulbrood, gave the coefficient of determination of 97.9, 92.7, 91.0, 93.5, and 85.2%, respectively. Four of them were multiplicative, and the remaining one for equine infectious anemia was additive. From the viewpoint of practical utility, there was little doubt that even these secular trends might be used for predicting the relevant morbidities with fairly good preciseness.
假设存在加法和乘法两种数学模型,作者估算了1949年至1975年期间家畜12种传染病的年发病率长期趋势。对于每种疾病,拟合了10条不同的趋势曲线。结果发现,5个回归方程,即牛毛滴虫病、牛结核病、马传染性贫血、鸡白痢和雏鸡坏疽性皮炎的回归方程,其判定系数分别为97.9%、92.7%、91.0%、93.5%和85.2%。其中4个是乘法模型,其余的马传染性贫血是加法模型。从实际应用的角度来看,毫无疑问,即使是这些长期趋势也可以用于以相当高的精度预测相关发病率。