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V-Lab

SMI Volatility Index Zero Slope Spline-GARCH Volatility Analysis

Volatility prediction for Friday, August 21st, 2026

1 Day

69.90%

decreased by 2.05%

1 Week

75.13%

increased by 3.18%

1 Month

83.57%

increased by 11.62%

Analysis last updated: Friday, August 21, 2026 at 08:17 PM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of SMI Volatility Index S0GARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Jan 4, 1999 to May 13, 2026

Model 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 5 trading days.

τ

Zero Slope Spline-GARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.8334
10.87***
α

ARCH

Response to squared shocks

0.1433
7.60***
β

GARCH

Volatility persistence

0.7160
20.89***
γi Spline Coefficients
K=4
γ1-0.0006
-0.07
γ20.0080
0.69
γ3-0.0186
-2.46**
γ40.0151
3.00***

Persistence:

0.859

Half-life:

5 days