V-Lab
NASDAQ Composite Index Zero Slope Spline-GARCH Volatility Analysis
Volatility prediction for Wednesday, September 9th, 2026
1 Day
15.96%
decreased by 0.50%
1 Week
16.47%
increased by 0.01%
1 Month
18.00%
increased by 1.54%
Analysis last updated: Wednesday, September 9, 2026 at 12:04 AM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 1, 1990 to Sep 4, 2026Model Insight
This model fits a time-varying baseline (a spline), so volatility mean-reverts toward a slowly-shifting long-run level rather than a constant. Short-run deviations decay with a half-life of 18 trading days.
τ
Zero Slope Spline-GARCH Model
Tap to view equation
Time-varying baseline: volatility reverts to a slowly-shifting spline trend
| Param | Value | t-stat |
|---|---|---|
| ωconst | 0.7535 | 7.37*** |
| αARCH | 0.1000 | 10.34*** |
| βGARCH | 0.8631 | 72.00*** |
Spline Coefficients
K=8
| γ1 | 0.0104 | 0.36 |
| γ2 | 0.0459 | 1.04 |
| γ3 | -0.1709 | -5.46*** |
| γ4 | 0.2038 | 7.19*** |
| γ5 | -0.1477 | -5.82*** |
| γ6 | 0.1064 | 3.83*** |
| γ7 | -0.0629 | -2.26** |
| γ8 | 0.0116 | 0.57 |
0.963
Persistence18d
Half-lifeτ
Zero Slope Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.7535 | 7.37*** |
α ARCH Response to squared shocks | 0.1000 | 10.34*** |
β GARCH Volatility persistence | 0.8631 | 72.00*** |
Spline Coefficients
K=8
| γ1 | 0.0104 | 0.36 |
| γ2 | 0.0459 | 1.04 |
| γ3 | -0.1709 | -5.46*** |
| γ4 | 0.2038 | 7.19*** |
| γ5 | -0.1477 | -5.82*** |
| γ6 | 0.1064 | 3.83*** |
| γ7 | -0.0629 | -2.26** |
| γ8 | 0.0116 | 0.57 |
Persistence:
0.963
Half-life:
18 days
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