One New Method on ARMA Model Parameters Estimation

摘要

Normal 0 7.8 ? 0 2 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable{mso-style-name:????;mso-tstyle-rowband-size:0;mso-tstyle-colband-size:0;mso-style-noshow:yes;mso-style-parent:"";mso-padding-alt:0cm 5.4pt 0cm 5.4pt;mso-para-margin:0cm;mso-para-margin-bottom:.0001pt;mso-pagination:widow-orphan;font-size:10.0pt;font-family:"Times New Roman";mso-fareast-font-family:"Times New Roman";mso-ansi-language:#0400;mso-fareast-language:#0400;mso-bidi-language:#0400;} The estimation of ARMA model parameters really belongs to the least-square problem,in ARMA model because the residual are calculated by given time series,the time series and parameter are nonlinear.However it is difficult to calculate the derivative of objective function.This paper substitutes derivative with difference,then calculate the first derivative and the second derivative of objective function.Finally we prove that, under suitable hypotheses, the proposed algorithm converges globally.