Coil Spline-GARCH Volatility Analysis
Volatility prediction for Tuesday, July 21st, 2026
1 Day
9.09%
unchanged at 0.00%
1 Week
10.56%
increased by 1.47%
1 Month
12.73%
increased by 3.64%
Analysis last updated: Tuesday, July 21, 2026 at 06:32 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Dec 7, 1999 to Jul 17, 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 4 trading days.
τ
Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 1.0452 | 5.83*** |
α ARCH Response to squared shocks | 0.2023 | 6.17*** |
β GARCH Volatility persistence | 0.6545 | 14.70*** |
Spline Coefficients
K=10
| γ1 | -0.0393 | -0.46 |
| γ2 | 0.0670 | 0.45 |
| γ3 | -0.0435 | -0.29 |
| γ4 | 0.0157 | 0.11 |
| γ5 | 0.0256 | 0.20 |
| γ6 | 0.0005 | 0.00 |
| γ7 | -0.2151 | -1.80* |
| γ8 | 0.4359 | 3.02*** |
| γ9 | -0.3781 | -1.98** |
| γ10 | -0.1071 | -0.43 |
Persistence:
0.857
Half-life:
4 days
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