V-Lab
Stock Exchange of Thailand SET Index Zero Slope Spline-GARCH Volatility Analysis
Volatility prediction for Friday, September 11th, 2026
1 Day
12.31%
decreased by 0.49%
1 Week
12.61%
decreased by 0.19%
1 Month
13.55%
increased by 0.75%
Analysis last updated: Friday, September 11, 2026 at 05:40 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 2, 1990 to Sep 7, 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 19 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 | 1.2754 | 6.15*** |
| αARCH | 0.1023 | 9.66*** |
| βGARCH | 0.8619 | 61.01*** |
Spline Coefficients
K=9
| γ1 | 0.0288 | 0.98 |
| γ2 | 0.0060 | 0.13 |
| γ3 | -0.1305 | -3.71*** |
| γ4 | 0.1998 | 4.82*** |
| γ5 | -0.1921 | -2.69*** |
| γ6 | 0.1136 | 1.30 |
| γ7 | -0.0014 | -0.02 |
| γ8 | -0.0227 | -0.46 |
| γ9 | -0.0107 | -0.30 |
0.964
Persistence19d
Half-lifeτ
Zero Slope Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 1.2754 | 6.15*** |
α ARCH Response to squared shocks | 0.1023 | 9.66*** |
β GARCH Volatility persistence | 0.8619 | 61.01*** |
Spline Coefficients
K=9
| γ1 | 0.0288 | 0.98 |
| γ2 | 0.0060 | 0.13 |
| γ3 | -0.1305 | -3.71*** |
| γ4 | 0.1998 | 4.82*** |
| γ5 | -0.1921 | -2.69*** |
| γ6 | 0.1136 | 1.30 |
| γ7 | -0.0014 | -0.02 |
| γ8 | -0.0227 | -0.46 |
| γ9 | -0.0107 | -0.30 |
Persistence:
0.964
Half-life:
19 days
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