stationary time series

There are a lot of time sequence model of non-stationary time series, first difference to eliminate the trend, meet the stable condition after modeling, namely ARIMA model, this paper finally selected as ARIMA model on TEC value prediction.

时间序列有很多的模型，对非平稳时间序列需先进行差分消除其趋势，满足平稳条件后再进行建模，即ARIMA模型，由于本文最后选定ARIMA模型对TEC值进行预测。

As a kind of important econometric model in specific forms, error correction model ( ECM) has a better effect in the study of non stationary time series and co-integration relationship of series.

误差修正模型（ECM）作为一种具有特定形式的重要的计量经济学模型，在研究非平稳时间序列以及序列间协整关系方面具有较好的效果。

In fact, vector spectrum comprises a' series of analysis methods: fundamental vector spectrum, vector power spectrum, vector spectrum that used to analysis stationary signals, and short time vector spectrum to non-stationary signals.

矢谱分析是针对旋转机械矢量信号的一系列分析方法的总称。矢谱范畴包括针对平稳信号的矢量谱、矢功率谱、矢量倒谱以及针对非平稳信号的短时矢谱等众多分析方法。

Especially, modern spectral estimation is not only of high resolution, but also able to process non stationary time series, so it is widely used.

特别是现代谱估计方法，既有高分辨率，又可以分析非平稳时间序列，具有广泛的应用。

In the first, with unit root test of non-stationary time series and the error correction model, we have established the error correction model to the multivariable second-order non-stationary time series.

结合非平稳时间序列单位根检验方法和误差修正模型机制，对多变量的二阶非平稳时间序列建立了误差修正模型。