基于HP滤波模型苜蓿草进口价格波动分析

Analysis of alfalfa import price fluctuation based on an HP filter model

本研究分析了2008年1月-2017年12月苜蓿草(Medicago sativa)进口价格的波动特征,运用Census X12季节调整模型消除季节性因素及不规则要素,进一步采用HP滤波模型将价格序列分解为趋势值序列和波动值序列,并划分波动周期。本研究揭示的苜蓿草进口价格波动和周期性变化规律对于畜牧企业进口贸易具有重要的意义,可以降低苜蓿干草价格波动带来的负面效应。

This study analyzed alfalfa（Medicago sativa）import price features based on data from January 2008 to December 2017.First,we analyzed the main characteristics of price fluctuation.Then,a seasonal adjustment model of Census X12 was used to eliminate the influence of seasonal factors and irregular factors.An HP filter decomposition model was further used to breakdown the price series into trend series and fluctuation series.Finally,the fluctuation period was divided.This study allows us to take advantage of the fluctuation and cyclical changes in alfalfa import price to guide enterprises in trade,so as to reduce the negative effects of price fluctuation.