Nikkei 225 Zero Slope Spline-GARCH Volatility Analysis
Volatility prediction for Friday, October 30th, 2026
1 Day
24.78%
decreased by 0.84%
1 Week
24.69%
decreased by 0.93%
1 Month
24.38%
decreased by 1.24%
Analysis last updated: Thursday, October 29, 2026 at 07:02 AM UTC
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News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 2, 1990 to Oct 23, 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 25 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 | 1.1342 | 10.56*** |
| αARCH | 0.1112 | 9.76*** |
| βGARCH | 0.8619 | 71.52*** |
Spline Coefficients
K=1
| γ1 | 0.0002 | 1.36 |
0.973
Persistence25d
Half-lifeτ
Zero Slope Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 1.1342 | 10.56*** |
α ARCH Response to squared shocks | 0.1112 | 9.76*** |
β GARCH Volatility persistence | 0.8619 | 71.52*** |
Spline Coefficients
K=1
| γ1 | 0.0002 | 1.36 |
Persistence:
0.973
Half-life:
25 days
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