V-Lab
S&P 1000 Index GJR-GARCH Volatility Analysis
Volatility prediction for Wednesday, August 19th, 2026
1 Day
15.26%
increased by 3.51%
1 Week
15.46%
increased by 3.71%
1 Month
16.17%
increased by 4.42%
Analysis last updated: Tuesday, August 18, 2026 at 11:06 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Dec 29, 1994 to Aug 14, 2026Model Insight
This asset exhibits a strong leverage effect: volatility responds almost entirely to negative shocks. The ARCH response to positive shocks is negligible.
σ
GJR-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.0286 | 23.74*** |
α ARCH Response to squared shocks | 0.0135 | 7.19*** |
β GARCH Volatility persistence | 0.8930 | 470.50*** |
γ leverage Additional response to negative shocks | 0.1523 | 30.11*** |
Persistence:
0.983
Half-life:
40 days
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