V-Lab
S&P/TSX Composite Index Zero Slope Spline-GARCH Volatility Analysis
Volatility prediction for Thursday, September 10th, 2026
1 Day
13.66%
decreased by 0.38%
1 Week
13.77%
decreased by 0.27%
1 Month
14.12%
increased by 0.08%
Analysis last updated: Wednesday, September 9, 2026 at 09:06 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 1, 1990 to Sep 8, 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 18 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 | 0.7373 | 4.52*** |
| αARCH | 0.1094 | 9.61*** |
| βGARCH | 0.8519 | 67.29*** |
Spline Coefficients
K=9
| γ1 | 0.0029 | 0.06 |
| γ2 | 0.0683 | 1.00 |
| γ3 | -0.1981 | -4.76*** |
| γ4 | 0.2399 | 6.67*** |
| γ5 | -0.1946 | -5.42*** |
| γ6 | 0.0994 | 2.59*** |
| γ7 | 0.0015 | 0.04 |
| γ8 | -0.0070 | -0.18 |
| γ9 | -0.0294 | -1.04 |
0.961
Persistence18d
Half-lifeτ
Zero Slope Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.7373 | 4.52*** |
α ARCH Response to squared shocks | 0.1094 | 9.61*** |
β GARCH Volatility persistence | 0.8519 | 67.29*** |
Spline Coefficients
K=9
| γ1 | 0.0029 | 0.06 |
| γ2 | 0.0683 | 1.00 |
| γ3 | -0.1981 | -4.76*** |
| γ4 | 0.2399 | 6.67*** |
| γ5 | -0.1946 | -5.42*** |
| γ6 | 0.0994 | 2.59*** |
| γ7 | 0.0015 | 0.04 |
| γ8 | -0.0070 | -0.18 |
| γ9 | -0.0294 | -1.04 |
Persistence:
0.961
Half-life:
18 days
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