V-Lab
CBOE S&P 500 One-Year Volatility Index GJR-GARCH Volatility Analysis
Volatility prediction for Friday, September 11th, 2026
1 Day
29.10%
increased by 0.85%
1 Week
31.69%
increased by 3.44%
1 Month
36.92%
increased by 8.67%
Analysis last updated: Friday, September 11, 2026 at 11:30 AM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 3, 2007 to Sep 4, 2026Model Insight
This asset shows a rare inverse leverage effect: volatility responds almost entirely to positive returns, rising far more after gains than after losses. This is the reverse of the usual leverage effect, rare among risky assets.
σ
GJR-GARCH Model
Tap to view equation
Inverse leverage: volatility responds almost entirely to positive returns
| Param | Value | t-stat |
|---|---|---|
| ωconst | 0.6505 | 7.51*** |
| αARCH | 0.3594 | 2.99*** |
| βGARCH | 0.6987 | 25.24*** |
| γleverage | -0.2997 | -2.17** |
0.908
Persistence7d
Half-lifeσ
GJR-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.6505 | 7.51*** |
α ARCH Response to squared shocks | 0.3594 | 2.99*** |
β GARCH Volatility persistence | 0.6987 | 25.24*** |
γ leverage Additional response to negative shocks | -0.2997 | -2.17** |
Persistence:
0.908
Half-life:
7 days
Other CBOE S&P 500 One-Year Volatility Index Analyses
Other GJR-GARCH Analyses on Volatility Indices