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V-Lab

S&P GSCI Silver Index AGARCH Volatility Analysis

Volatility prediction for Tuesday, August 18th, 2026

1 Day

39.42%

decreased by 0.77%

1 Week

39.36%

decreased by 0.83%

1 Month

39.09%

decreased by 1.10%

Analysis last updated: Monday, August 17, 2026 at 11:04 PM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of S&P GSCI Silver Index AGARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Jan 2, 1990 to Aug 14, 2026

Model Insight

With persistence 0.995, volatility shocks have a half-life of 146 trading days (~0.6 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate.

Asymmetry: positive returns raise volatility more

σ

AGARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.0077
4.56***
α

ARCH

Response to squared shocks

0.0435
30.55***
β

GARCH

Volatility persistence

0.9517
663.23***
γ

leverage

Additional response to negative shocks

-0.5012
-13.06***

Persistence:

0.995

Half-life:

146 days