পদ্ধতির তুলনা করুন

	টাইম-ভ্যারিং প্যারামিটার ইজিএআরসিএইচ মডেল	ইগার্চ মডেল (এক্সপোনেনশিয়াল GARCH)
ক্ষেত্র	অর্থমিতি	অর্থমিতি
পরিবার	Regression model	Regression model
উদ্ভবের বছর	1991–2000s	1991
প্রবর্তক	Nelson (1991) for EGARCH; TVP extension developed across the 1990s–2000s literature (e.g., Harvey, Engle and co-authors)	Daniel B. Nelson
ধরন	Conditional volatility model	Volatility / conditional variance model
মৌলিক উৎস	Nelson, D. B. (1991). Conditional heteroskedasticity in asset returns: A new approach. Econometrica, 59(2), 347–370.	Nelson, D. B. (1991). Conditional heteroskedasticity in asset returns: A new approach. Econometrica, 59(2), 347–370.
অপর নাম	TVP-EGARCH, time-varying EGARCH, EGARCH with time-varying parameters, dynamic parameter EGARCH	Exponential GARCH, EGARCH, Nelson EGARCH, log-GARCH
সম্পর্কিত	3	6
সারসংক্ষেপ	The TVP-EGARCH model extends Nelson's (1991) Exponential GARCH by allowing the volatility equation's parameters — including the leverage effect coefficient — to drift continuously over time. This makes it possible to capture structural change and regime evolution in financial return volatility without imposing a fixed break date.	The Exponential GARCH (EGARCH) model, introduced by Nelson (1991), extends the standard GARCH framework by modelling the logarithm of conditional variance. This ensures variance is always positive without parameter constraints and, crucially, allows negative and positive shocks to have asymmetric effects on volatility — capturing the well-known leverage effect in financial markets.