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

Volatility prediction for Tuesday, July 21st, 2026

1 Day

17.23%

increased by 1.54%

1 Week

17.34%

increased by 1.65%

1 Month

17.76%

increased by 2.07%

Analysis last updated: Monday, July 20, 2026 at 11:10 PM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

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

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Jan 2, 1990 to Jul 17, 2026

Model Insight

Volatility shocks decay with a half-life of 58 trading days, meaning a shock loses half its impact after approximately 58 days. Returns follow a Student-t distribution with v = 6.85 degrees of freedom, capturing fatter tails than a normal distribution.

𝑓

GAS-GARCH-T Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

1.8553
8.30***
α

ARCH

Response to squared shocks

0.0558
34.16***
β

GARCH

Volatility persistence

0.9882
695.39***
ν

DF

Student-t tail thickness

6.8531
5.89***

Persistence:

0.988

Half-life:

58 days