V-Lab
Ibovespa Brasil Sao Paulo Stock Exchange Index Zero Slope Spline-GARCH Volatility Analysis
Volatility prediction for Monday, August 17th, 2026
1 Day
18.22%
decreased by 0.77%
1 Week
18.33%
decreased by 0.66%
1 Month
18.65%
decreased by 0.34%
Analysis last updated: Friday, August 14, 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 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 21 trading days.
τ
Zero Slope Spline-GARCH Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 4.6050 | 5.90*** |
α ARCH Response to squared shocks | 0.0823 | 8.01*** |
β GARCH Volatility persistence | 0.8856 | 75.40*** |
Spline Coefficients
K=4
| γ1 | 0.0351 | 5.36*** |
| γ2 | -0.0373 | -4.17*** |
| γ3 | 0.0018 | 0.38 |
| γ4 | 0.0029 | 0.95 |
Persistence:
0.968
Half-life:
21 days
Other Ibovespa Brasil Sao Paulo Stock Exchange Index Analyses
Other Zero Slope Spline-GARCH Analyses on Equity Indices