Shanghai Shenzhen CSI 300 Index GAS-GARCH Student T Volatility Analysis
Volatility prediction for Tuesday, July 21st, 2026
1 Day
32.02%
decreased by 0.05%
1 Week
31.99%
decreased by 0.08%
1 Month
31.84%
decreased by 0.23%
Analysis last updated: Monday, July 20, 2026 at 08:02 AM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Apr 8, 2005 to Jul 17, 2026Model Insight
With persistence 0.996, volatility shocks have a half-life of 163 trading days (~0.6 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate. Returns follow a Student-t distribution with v = 4.75 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 | 2.9414 | 4.77*** |
α ARCH Response to squared shocks | 0.0512 | 48.80*** |
β GARCH Volatility persistence | 0.9957 | 1,286.50*** |
ν DF Student-t tail thickness | 4.7469 | 15.32*** |
Persistence:
0.996
Half-life:
163 days
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