V-Lab
S&P MidCap 400 Index GAS-GARCH Student T Volatility Analysis
Volatility prediction for Monday, August 10th, 2026
1 Day
15.67%
increased by 1.06%
1 Week
15.75%
increased by 1.14%
1 Month
16.05%
increased by 1.44%
Analysis last updated: Friday, August 7, 2026 at 11:11 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 1, 1990 to Aug 7, 2026Model Insight
Volatility shocks decay with a half-life of 52 trading days, meaning a shock loses half its impact after approximately 52 days. Returns follow a Student-t distribution with v = 10.92 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 | 1.3702 | 11.03*** |
α ARCH Response to squared shocks | 0.0887 | 36.96*** |
β GARCH Volatility persistence | 0.9867 | 706.77*** |
ν DF Student-t tail thickness | 10.9188 | 4.50*** |
Persistence:
0.987
Half-life:
52 days
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