V-Lab
S&P 500 Scored & Screened Index (ESG) GAS-GARCH Student T Volatility Analysis
Volatility prediction for Thursday, August 20th, 2026
1 Day
11.86%
decreased by 0.93%
1 Week
12.09%
decreased by 0.70%
1 Month
12.91%
increased by 0.12%
Analysis last updated: Wednesday, August 19, 2026 at 11:07 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Apr 28, 2005 to Aug 14, 2026Model Insight
Volatility shocks decay with a half-life of 44 trading days, meaning a shock loses half its impact after approximately 44 days. Returns follow a Student-t distribution with v = 6.35 degrees of freedom, capturing fatter tails than a normal distribution.
𝑓
GAS-GARCH-T Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 1.2795 | 5.98*** |
α ARCH Response to squared shocks | 0.1085 | 31.94*** |
β GARCH Volatility persistence | 0.9843 | 352.28*** |
ν DF Student-t tail thickness | 6.3541 | 7.61*** |
Persistence:
0.984
Half-life:
44 days
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