V-Lab
Stock Exchange of Thailand SET Index Spline-GARCH Volatility Analysis
Volatility prediction for Friday, September 11th, 2026
1 Day
13.90%
decreased by 0.45%
1 Week
14.45%
increased by 0.10%
1 Month
16.08%
increased by 1.73%
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
Spline-GARCH Model
Tap to view equation
Time-varying baseline: volatility reverts to a slowly-shifting spline trend
| Param | Value | t-stat |
|---|---|---|
| ωconst | 1.2734 | 6.21*** |
| αARCH | 0.1022 | 9.64*** |
| βGARCH | 0.8612 | 60.75*** |
Spline Coefficients
K=9
| γ1 | 0.0225 | 0.77 |
| γ2 | 0.0192 | 0.43 |
| γ3 | -0.1442 | -4.14*** |
| γ4 | 0.2125 | 5.32*** |
| γ5 | -0.2007 | -2.90*** |
| γ6 | 0.1141 | 1.33 |
| γ7 | 0.0104 | 0.16 |
| γ8 | -0.0530 | -0.97 |
| γ9 | 0.0625 | 1.04 |
0.963
Persistence19d
Half-lifeτ
Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 1.2734 | 6.21*** |
α ARCH Response to squared shocks | 0.1022 | 9.64*** |
β GARCH Volatility persistence | 0.8612 | 60.75*** |
Spline Coefficients
K=9
| γ1 | 0.0225 | 0.77 |
| γ2 | 0.0192 | 0.43 |
| γ3 | -0.1442 | -4.14*** |
| γ4 | 0.2125 | 5.32*** |
| γ5 | -0.2007 | -2.90*** |
| γ6 | 0.1141 | 1.33 |
| γ7 | 0.0104 | 0.16 |
| γ8 | -0.0530 | -0.97 |
| γ9 | 0.0625 | 1.04 |
Persistence:
0.963
Half-life:
19 days
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