V-Lab
S&P 500 Scored & Screened Index (ESG) Zero Slope Spline-GARCH Volatility Analysis
Volatility prediction for Wednesday, August 19th, 2026
1 Day
13.35%
increased by 0.13%
1 Week
13.80%
increased by 0.58%
1 Month
15.16%
increased by 1.94%
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
Apr 28, 2005 to Aug 14, 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 20 trading days.
τ
Zero Slope Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 0.6613 | 6.38*** |
α ARCH Response to squared shocks | 0.1280 | 8.78*** |
β GARCH Volatility persistence | 0.8381 | 51.00*** |
Spline Coefficients
K=3
| γ1 | -0.0391 | -3.52*** |
| γ2 | 0.0619 | 3.60*** |
| γ3 | -0.0312 | -3.27*** |
Persistence:
0.966
Half-life:
20 days
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