V-Lab
Tadawul All Share TASI Index APARCH Volatility Analysis
Volatility prediction for Saturday, September 26th, 2026
1 Day
12.59%
1 Week
13.30%
1 Month
15.65%
Analysis last updated: Wednesday, September 23, 2026 at 05:43 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Oct 19, 1998 to Sep 22, 2026Model Insight
This asset exhibits a strong leverage effect: negative returns increase next-day volatility 115% more than equivalent positive returns. The volatility power δ = 1.33 sits below 2, so large shocks influence volatility less than quadratically, a more outlier-robust response than standard GARCH.
APARCH Model
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| Param | Value | t-stat |
|---|---|---|
| ωconst | 0.0486 | 6.97*** |
| αARCH | 0.1762 | 11.04*** |
| βGARCH | 0.8238 | 56.26*** |
| γleverage | 0.2796 | 5.16*** |
| δpower | 1.3335 | 9.14*** |
0.973
Persistence25d
Half-lifeAPARCH Model
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| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.0486 | 6.97*** |
α ARCH Response to squared shocks | 0.1762 | 11.04*** |
β GARCH Volatility persistence | 0.8238 | 56.26*** |
γ leverage Additional response to negative shocks | 0.2796 | 5.16*** |
δ power Transformation power | 1.3335 | 9.14*** |
Persistence:
0.973
Half-life:
25 days
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