NASDAQ 100 Zero Slope Spline-GARCH Volatility Analysis
Volatility prediction for Friday, July 17th, 2026
1 Day
22.90%
increased by 0.30%
1 Week
22.84%
increased by 0.24%
1 Month
22.67%
increased by 0.07%
Analysis last updated: Friday, July 17, 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 Jul 10, 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 21 trading days.
τ
Zero Slope Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.9331 | 8.25*** |
α ARCH Response to squared shocks | 0.0905 | 10.30*** |
β GARCH Volatility persistence | 0.8772 | 80.36*** |
Spline Coefficients
K=8
| γ1 | 0.0126 | 0.49 |
| γ2 | 0.0297 | 0.71 |
| γ3 | -0.1484 | -4.66*** |
| γ4 | 0.1926 | 6.86*** |
| γ5 | -0.1389 | -5.43*** |
| γ6 | 0.0998 | 3.54*** |
| γ7 | -0.0651 | -2.30** |
| γ8 | 0.0159 | 0.76 |
Persistence:
0.968
Half-life:
21 days
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