V-Lab
Russell Midcap Index GJR-GARCH Volatility Analysis
Volatility prediction for Friday, September 18th, 2026
1 Day
13.58%
decreased by 0.52%
1 Week
13.77%
decreased by 0.33%
1 Month
14.40%
increased by 0.30%
Analysis last updated: Friday, September 18, 2026 at 09:53 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Mar 1, 2004 to Sep 10, 2026Model Insight
This asset exhibits a strong leverage effect: volatility responds almost entirely to negative shocks. The ARCH response to positive shocks is negligible.
σ
GJR-GARCH Model
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Leverage: volatility responds almost entirely to negative shocks
| Param | Value | t-stat |
|---|---|---|
| ωconst | 0.0272 | 4.17*** |
| αARCH | 0.0071 | 0.65 |
| βGARCH | 0.8869 | 92.51*** |
| γleverage | 0.1663 | 6.65*** |
0.977
Persistence30d
Half-lifeσ
GJR-GARCH Model
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| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.0272 | 4.17*** |
α ARCH Response to squared shocks | 0.0071 | 0.65 |
β GARCH Volatility persistence | 0.8869 | 92.51*** |
γ leverage Additional response to negative shocks | 0.1663 | 6.65*** |
Persistence:
0.977
Half-life:
30 days
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