农业基础科学

农业基础科学

来源出版物：Journal of Integrative Agriculture，2015，14（6）： 1115-1121联系邮箱：ZHAO Guo-qing，zhaogq@ruc.edu.cn

封面介绍：Development of hog industry plays a pivotal role in China’s economic growth and the daily life of Chinese people. In this study，the evolution path of China’s pork price is analyzed based on a selfexciting threshold autoregressive（SETAR）model. The empirical results show that the pork price series can be characterized by a unit root process in each regime. The series of price changes exhibit the property of a SETAR（2）process and can be divided into an expansion regime and a mild regime. Employing SETAR model without considering the heteroskedasticity in pork price series largely affects the test results and yield misspecification of the threshold parameters. See pages 1115-1121 by ZHAO and WU for details.

Nonlinear dynamics of pork price in China

ZHAO Guo-qing，WU Qiong

This paper primarily analyzes the evolution path of China’s pork price by employing the threshold autoregression model（TAR）. Considering the unit root test with a threshold effect and heteroskedasticity of the TAR model，we show that the pork price series is a unit root process in each regime，and the heteroskedasticity in the TAR model greatly affects the results of linearity test. We find that the changing process of pork price has two regimes： mild regime and expansion regime. In particular，a change belongs to an expansion regime if it is larger than 0.5881； otherwise，it falls in the mild regime.

pork price； heteroskedasticity； TAR unit root