V-Lab
CBOE Skew Index GAS-GARCH Student T Volatility Analysis
Volatility prediction for Friday, September 11th, 2026
1 Day
35.78%
decreased by 0.37%
1 Week
36.08%
decreased by 0.07%
1 Month
37.13%
increased by 0.98%
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 2, 1990 to Sep 4, 2026Model Insight
Volatility shocks decay with a half-life of 48 trading days, meaning a shock loses half its impact after approximately 48 days. Returns follow a Student-t distribution with v = 4.39 degrees of freedom, capturing fatter tails than a normal distribution.
𝑓
GAS-GARCH-T Model
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Shock decay: Shocks decay with a 48-day half-lifev = 4.39 · fat tails
| Param | Value | t-stat |
|---|---|---|
| ωconst | 8.0338 | 1.28 |
| αARCH | 0.1013 | 10.89*** |
| βGARCH | 0.9855 | 91.64*** |
| νDF | 4.3902 | 4.04*** |
0.986
Persistence48d
Half-life𝑓
GAS-GARCH-T Model
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| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 8.0338 | 1.28 |
α ARCH Response to squared shocks | 0.1013 | 10.89*** |
β GARCH Volatility persistence | 0.9855 | 91.64*** |
ν DF Student-t tail thickness | 4.3902 | 4.04*** |
Persistence:
0.986
Half-life:
48 days
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