V-Lab
Russell 1000 Value Index Zero Slope Spline-GARCH Volatility Analysis
Volatility prediction for Tuesday, September 15th, 2026
1 Day
10.63%
decreased by 0.52%
1 Week
10.92%
decreased by 0.23%
1 Month
11.87%
increased by 0.72%
Analysis last updated: Tuesday, September 15, 2026 at 12:04 AM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
May 12, 2000 to Sep 11, 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 32 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 | 0.9790 | 7.87*** |
| αARCH | 0.1154 | 9.71*** |
| βGARCH | 0.8629 | 70.25*** |
Spline Coefficients
K=1
| γ1 | 0.0003 | 1.00 |
0.978
Persistence32d
Half-lifeτ
Zero Slope Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.9790 | 7.87*** |
α ARCH Response to squared shocks | 0.1154 | 9.71*** |
β GARCH Volatility persistence | 0.8629 | 70.25*** |
Spline Coefficients
K=1
| γ1 | 0.0003 | 1.00 |
Persistence:
0.978
Half-life:
32 days
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