V-Lab
HP Inc Zero Slope Spline-GARCH Volatility Analysis
Volatility prediction for Thursday, September 10th, 2026
1 Day
44.22%
increased by 0.64%
1 Week
43.71%
increased by 0.13%
1 Month
42.12%
decreased by 1.46%
Analysis last updated: Wednesday, September 9, 2026 at 09:40 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 2, 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 16 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 | 0.9335 | 7.01*** |
| αARCH | 0.0429 | 4.68*** |
| βGARCH | 0.9138 | 55.52*** |
Spline Coefficients
K=9
| γ1 | -0.0407 | -0.74 |
| γ2 | 0.1078 | 1.28 |
| γ3 | -0.1456 | -2.80*** |
| γ4 | 0.0800 | 1.87* |
| γ5 | 0.0714 | 1.73* |
| γ6 | -0.1459 | -3.25*** |
| γ7 | 0.1223 | 2.84*** |
| γ8 | -0.0685 | -1.50 |
| γ9 | 0.0193 | 0.46 |
0.957
Persistence16d
Half-lifeτ
Zero Slope Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.9335 | 7.01*** |
α ARCH Response to squared shocks | 0.0429 | 4.68*** |
β GARCH Volatility persistence | 0.9138 | 55.52*** |
Spline Coefficients
K=9
| γ1 | -0.0407 | -0.74 |
| γ2 | 0.1078 | 1.28 |
| γ3 | -0.1456 | -2.80*** |
| γ4 | 0.0800 | 1.87* |
| γ5 | 0.0714 | 1.73* |
| γ6 | -0.1459 | -3.25*** |
| γ7 | 0.1223 | 2.84*** |
| γ8 | -0.0685 | -1.50 |
| γ9 | 0.0193 | 0.46 |
Persistence:
0.957
Half-life:
16 days
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