V-Lab
Russell Midcap Index Zero Slope Spline-GARCH Volatility Analysis
Volatility prediction for Friday, September 4th, 2026
1 Day
13.54%
increased by 0.71%
1 Week
13.96%
increased by 1.13%
1 Month
15.25%
increased by 2.42%
Analysis last updated: Friday, September 4, 2026 at 11:26 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Mar 1, 2004 to Aug 27, 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 24 trading days.
τ
Zero Slope Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.5166 | 5.74*** |
α ARCH Response to squared shocks | 0.1186 | 9.54*** |
β GARCH Volatility persistence | 0.8532 | 62.18*** |
Spline Coefficients
K=3
| γ1 | -0.0442 | -3.85*** |
| γ2 | 0.0637 | 3.89*** |
| γ3 | -0.0259 | -3.34*** |
Persistence:
0.972
Half-life:
24 days
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