V-Lab
NASDAQ Composite Index GAS-GARCH Student T Volatility Analysis
Volatility prediction for Monday, September 14th, 2026
1 Day
14.89%
1 Week
15.06%
1 Month
15.68%
Analysis last updated: Saturday, September 12, 2026 at 12:55 AM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 1, 1990 to Sep 11, 2026Model Insight
With persistence 0.990, volatility shocks have a half-life of 70 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 = 9.31 degrees of freedom, capturing fatter tails than a normal distribution.
GAS-GARCH-T Model
Tap to view equation
| Param | Value | t-stat |
|---|---|---|
| ωconst | 1.9093 | 1.88* |
| αARCH | 0.0860 | 9.57*** |
| βGARCH | 0.9901 | 166.21*** |
| νDF | 9.3069 | 1.38 |
0.990
Persistence70d
Half-lifeGAS-GARCH-T Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 1.9093 | 1.88* |
α ARCH Response to squared shocks | 0.0860 | 9.57*** |
β GARCH Volatility persistence | 0.9901 | 166.21*** |
ν DF Student-t tail thickness | 9.3069 | 1.38 |
Persistence:
0.990
Half-life:
70 days
Other NASDAQ Composite Index Analyses
Other GAS-GARCH Student T Analyses on Equity Indices