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V-Lab

CBOE EFA ETF Volatility Index GAS-GARCH Student T Volatility Analysis

Volatility prediction for Thursday, October 1st, 2026

1 Day

207.14%

decreased by 22.94%

1 Week

202.26%

decreased by 27.82%

1 Month

188.04%

decreased by 42.04%

Analysis last updated: Thursday, October 1, 2026 at 11:35 AM UTC

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Date Range:

from

09/30/2024

to

09/30/2026

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of CBOE EFA ETF Volatility Index GAS-GARCH-T

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Jan 2, 2008 to Sep 25, 2026

Model Insight

Volatility shocks decay with a half-life of 12 trading days, meaning a shock loses half its impact after approximately 12 days. Returns follow a Student-t distribution with v = 3.83 degrees of freedom, capturing fatter tails than a normal distribution.

𝑓

GAS-GARCH-T Model

Tap to view equation

Shock decay: Shocks decay with a 12-day half-lifev = 3.83 · fat tails
ParamValuet-stat
ωconst97.3368
2.18**
αARCH0.1266
6.92***
βGARCH0.9425
39.03***
νDF3.8302
3.22***

0.942

Persistence

12d

Half-life
𝑓

GAS-GARCH-T Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

97.3368
2.18**
α

ARCH

Response to squared shocks

0.1266
6.92***
β

GARCH

Volatility persistence

0.9425
39.03***
ν

DF

Student-t tail thickness

3.8302
3.22***

Persistence:

0.942

Half-life:

12 days