V-Lab
Borsa Istanbul 100 Index GJR-GARCH Volatility Analysis
Volatility prediction for Monday, August 17th, 2026
1 Day
22.32%
decreased by 0.62%
1 Week
22.74%
decreased by 0.20%
1 Month
24.31%
increased by 1.37%
Analysis last updated: Friday, August 14, 2026 at 03:04 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 1, 1990 to Aug 14, 2026Model Insight
With persistence 0.997, volatility shocks have a half-life of 261 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 | 0.0426 | 17.20*** |
α ARCH Response to squared shocks | 0.0671 | 16.01*** |
β GARCH Volatility persistence | 0.9250 | 401.14*** |
γ leverage Additional response to negative shocks | 0.0105 | 1.42 |
Persistence:
0.997
Half-life:
261 days
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