V-Lab
S&P/TSX Composite Index APARCH Volatility Analysis
Volatility prediction for Monday, August 10th, 2026
1 Day
11.49%
decreased by 0.35%
1 Week
11.65%
decreased by 0.19%
1 Month
12.20%
increased by 0.36%
Analysis last updated: Friday, August 7, 2026 at 09:02 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 1, 1990 to Aug 7, 2026Model Insight
This asset exhibits a strong leverage effect: negative returns increase next-day volatility 252% more than equivalent positive returns. The volatility power δ = 1.07 sits below 2, so large shocks influence volatility less than quadratically, a more outlier-robust response than standard GARCH.
σ
APARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.0181 | 32.34*** |
α ARCH Response to squared shocks | 0.0925 | 40.03*** |
β GARCH Volatility persistence | 0.9066 | 437.14*** |
γ leverage Additional response to negative shocks | 0.5267 | 33.39*** |
δ power Transformation power | 1.0745 | 35.84*** |
Persistence:
0.982
Half-life:
37 days
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