手法を比較

	フーリエTGARCHモデル	フーリエ GARCH モデル
分野	計量経済学	計量経済学
系統	Regression model	Regression model
提唱年	1994 / 2012	2000–2012
提唱者	Zakoian (1994) for TGARCH; Enders and Lee (2012) for Fourier approximation framework	Ludlow & Enders (2000); extended by Enders & Lee (2012) Fourier framework
種類	Volatility model with asymmetric leverage and Fourier smooth breaks	Volatility model
原典	Zakoian, J.-M. (1994). Threshold heteroskedastic models. Journal of Economic Dynamics and Control, 18(5), 931-955.	Ludlow, J., & Enders, W. (2000). Estimating non-linear ARMA models using Fourier coefficients. International Journal of Forecasting, 16(3), 333–347.
別名	Fourier TGARCH, Fourier Threshold GARCH, Fourier GJR-GARCH, smooth structural break TGARCH	Fourier GARCH, Fourier-flexible GARCH, GARCH with Fourier terms, smooth-break GARCH
関連	5	5
概要	The Fourier TGARCH model extends the Threshold GARCH framework by embedding Fourier trigonometric terms in the conditional variance equation to capture smooth, gradual structural breaks in volatility dynamics. It jointly models asymmetric leverage effects — where negative shocks amplify volatility more than positive shocks of the same magnitude — and time-varying intercept shifts caused by unobserved structural change.	The Fourier GARCH model embeds trigonometric Fourier terms into a standard GARCH framework to capture smooth, gradual shifts in the conditional variance process without requiring knowledge of exact structural break dates. By approximating unknown break patterns with sinusoidal functions, it jointly models volatility clustering and time-varying unconditional variance.