V-Lab
S&P MidCap 400 Index GAS-GARCH Student T Volatility Analysis
Volatility prediction for Friday, July 24th, 2026
1 Day
12.49%
decreased by 0.46%
1 Week
12.69%
decreased by 0.26%
1 Month
13.39%
increased by 0.44%
Analysis last updated: Thursday, July 23, 2026 at 11:01 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 1, 1990 to Jul 17, 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 = 10.90 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 | 1.3689 | 11.01*** |
α ARCH Response to squared shocks | 0.0888 | 36.95*** |
β GARCH Volatility persistence | 0.9867 | 705.26*** |
ν DF Student-t tail thickness | 10.9022 | 4.51*** |
Persistence:
0.987
Half-life:
52 days
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