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V-Lab
V-Lab

S&P GSCI Zinc Index GAS-GARCH Student T Volatility Analysis

Volatility prediction for Monday, September 21st, 2026

1 Day

23.23%

decreased by 0.04%

1 Week

23.24%

decreased by 0.03%

1 Month

23.27%

decreased by 0.00%

Analysis last updated: Saturday, September 19, 2026 at 12:03 AM UTC

Date Range:

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to

6M ·

1Y ·

2Y ·

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10Y ·

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graph of S&P GSCI Zinc Index GAS-GARCH-T

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Jan 7, 1991 to Sep 18, 2026

Model Insight

With persistence 0.997, volatility shocks have a half-life of 269 trading days (~1.1 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate. Returns follow a Student-t distribution with v = 6.24 degrees of freedom, capturing fatter tails than a normal distribution.

𝑓

GAS-GARCH-T Model

Tap to view equation

High persistence: persistence 0.997, shock half-life ~269 daysv = 6.24 · fat tails
ParamValuet-stat
ωconst2.4336
1.68*
αARCH0.0299
12.93***
βGARCH0.9974
555.67***
νDF6.2417
3.14***

0.997

Persistence

269d

Half-life
𝑓

GAS-GARCH-T Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

2.4336
1.68*
α

ARCH

Response to squared shocks

0.0299
12.93***
β

GARCH

Volatility persistence

0.9974
555.67***
ν

DF

Student-t tail thickness

6.2417
3.14***

Persistence:

0.997

Half-life:

269 days