V-Lab
S&P GSCI Corn Index GAS-GARCH Student T Volatility Analysis
Volatility prediction for Monday, July 27th, 2026
1 Day
22.69%
decreased by 1.11%
1 Week
22.72%
decreased by 1.08%
1 Month
22.83%
decreased by 0.97%
Analysis last updated: Friday, July 24, 2026 at 11:12 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 2, 1990 to Jul 24, 2026Model Insight
With persistence 0.990, volatility shocks have a half-life of 69 trading days (~0.3 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate. Returns follow a Student-t distribution with v = 7.15 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 | 2.3225 | 8.03*** |
α ARCH Response to squared shocks | 0.0648 | 37.59*** |
β GARCH Volatility persistence | 0.9900 | 746.08*** |
ν DF Student-t tail thickness | 7.1499 | 7.52*** |
Persistence:
0.990
Half-life:
69 days
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