V-Lab
Ibovespa Brasil Sao Paulo Stock Exchange Index Zero Slope Spline-GARCH Volatility Analysis
Volatility prediction for Friday, July 24th, 2026
1 Day
18.63%
decreased by 0.68%
1 Week
18.70%
decreased by 0.61%
1 Month
18.93%
decreased by 0.38%
Analysis last updated: Thursday, July 23, 2026 at 09:02 PM UTC
News Impact Curve
How returns affect tomorrow's volatilityVolatility Forecast
How volatility evolves over timeParameter Estimates
Jan 2, 1990 to Jul 17, 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 21 trading days.
τ
Zero Slope Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 4.6109 | 5.90*** |
α ARCH Response to squared shocks | 0.0825 | 8.01*** |
β GARCH Volatility persistence | 0.8852 | 75.14*** |
Spline Coefficients
K=4
| γ1 | 0.0353 | 5.36*** |
| γ2 | -0.0375 | -4.18*** |
| γ3 | 0.0018 | 0.37 |
| γ4 | 0.0030 | 0.97 |
Persistence:
0.968
Half-life:
21 days
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