S&P GSCI Cotton Index GAS-GARCH Student T Volatility Analysis
Volatility prediction for Friday, July 17th, 2026
1 Day
25.76%
increased by 1.52%
1 Week
25.75%
increased by 1.51%
1 Month
25.70%
increased by 1.46%
Analysis last updated: Thursday, July 16, 2026 at 11:03 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 2, 1990 to Jul 10, 2026Model Insight
With persistence 0.994, volatility shocks have a half-life of 106 trading days (~0.4 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate. Returns follow a Student-t distribution with v = 6.88 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 | 2.4516 | 6.31*** |
α ARCH Response to squared shocks | 0.0406 | 28.98*** |
β GARCH Volatility persistence | 0.9935 | 867.69*** |
ν DF Student-t tail thickness | 6.8825 | 5.90*** |
Persistence:
0.994
Half-life:
106 days
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