手法を比較

	時変パラメータARCHモデル（TVP-ARCH）	ARCHモデル（Autoregressive Conditional Heteroskedasticity）
分野	計量経済学	計量経済学
系統	Regression model	Regression model
提唱年	1980s–1990s	1982
提唱者	Extension of Engle (1982) ARCH; TVP-ARCH formalization credited to Nicholls & Quinn and subsequent state-space literature	Robert F. Engle
種類	Conditional heteroscedasticity model with time-varying coefficients	Conditional volatility model
原典	Engle, R. F. (1982). Autoregressive conditional heteroscedasticity with estimates of the variance of United Kingdom inflation. Econometrica, 50(4), 987–1007.	Engle, R. F. (1982). Autoregressive conditional heteroscedasticity with estimates of the variance of United Kingdom inflation. Econometrica, 50(4), 987–1007.
別名	TVP-ARCH, time-varying ARCH, adaptive ARCH, state-space ARCH	ARCH, autoregressive conditional heteroskedasticity, Engle ARCH, conditional variance model
関連	5	6
概要	The Time-Varying Parameter ARCH (TVP-ARCH) model extends the classic ARCH framework by allowing both the conditional mean coefficients and the ARCH variance parameters to drift over time according to a random-walk or state-space process. This makes it possible to capture structural shifts in volatility dynamics without imposing a fixed parameter regime.	The ARCH model, introduced by Robert Engle in 1982, captures time-varying volatility in financial and macroeconomic time series. It models the conditional variance of today's error as a function of past squared errors, explaining why volatile periods cluster together — a phenomenon known as volatility clustering.