V-Lab
Japan Petroleum Ex Zero Slope Spline-GARCH Volatility Analysis
Volatility prediction for Friday, September 11th, 2026
1 Day
29.88%
decreased by 0.67%
1 Week
30.71%
increased by 0.16%
1 Month
32.88%
increased by 2.33%
Analysis last updated: Friday, September 11, 2026 at 07:57 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Dec 10, 2003 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 11 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 | 0.9803 | 14.25*** |
| αARCH | 0.1042 | 7.43*** |
| βGARCH | 0.8354 | 39.37*** |
Spline Coefficients
K=1
| γ1 | -0.0001 | -0.25 |
0.940
Persistence11d
Half-lifeτ
Zero Slope Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.9803 | 14.25*** |
α ARCH Response to squared shocks | 0.1042 | 7.43*** |
β GARCH Volatility persistence | 0.8354 | 39.37*** |
Spline Coefficients
K=1
| γ1 | -0.0001 | -0.25 |
Persistence:
0.940
Half-life:
11 days
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