V-Lab
Borsa Istanbul 100 Index GJR-GARCH Volatility Analysis
Volatility prediction for Monday, July 27th, 2026
1 Day
22.82%
decreased by 0.24%
1 Week
23.22%
increased by 0.16%
1 Month
24.76%
increased by 1.70%
Analysis last updated: Friday, July 24, 2026 at 04:05 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 1, 1990 to Jul 24, 2026Model Insight
With persistence 0.997, volatility shocks have a half-life of 262 trading days (~1.0 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate.
σ
GJR-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.0428 | 17.20*** |
α ARCH Response to squared shocks | 0.0671 | 15.99*** |
β GARCH Volatility persistence | 0.9250 | 400.43*** |
γ leverage Additional response to negative shocks | 0.0104 | 1.41 |
Persistence:
0.997
Half-life:
262 days
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