Parameter Estimation Method In Logistic Model

As one of the core theory of population ecology, Logistic model is Is an effective data processing method, and it widely used widely used in medicine, economics, biology technology etc.Logistic model proposed in1838by the Belgian mathematician Verhulst, which is after the model study of Malthus on population. In a hundred years of history, the generation and application of Logistic model has important significance. Through dividing three key moments of Logistic growth curve, the paper analysis the image,and give the effective and scientific explanation of the model.The equation of Logistic model isy=K/1+ea-rt. After a simple deformation to this equation, three-point method can be used, or four-point method in the model to estimate the K value. Then under the principle of least squares after using Eviews software linear regression to estimate the remaining two parameters. This method is simple, for the two parameters a and r is estimated mainly by means of Eviews software, very little memory space occupied by Eviews software, installation operations are easy to learn. Because the estimation parameters a and r is completely dependent on the estimation of K value, so the accuracy of this method is a little lacking comparing to the method of three parameters simultaneous estimation.The instances selected are mainly for the analysis and forecasting on social ownership of durables consumer as well as instances of population growth.The selected examples show that this method is still able to provide a better prediction on durables consumer and the size of the population. The estimation value obtained using this method can also be used as an initial value to other iterative methods. experiments and comparative analysis show that this method is effective.