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CBOE S&P 500 Spot Volatility Index GAS-GARCH Student T Volatility Analysis

Volatility prediction for Monday, October 5th, 2026

1 Day

197.26%

increased by 22.20%

1 Week

201.05%

increased by 25.99%

1 Month

211.60%

increased by 36.54%

Analysis last updated: Monday, October 5, 2026 at 11:32 AM UTC

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Date Range:

from

10/02/2024

to

10/02/2026

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of CBOE S&P 500 Spot Volatility Index GAS-GARCH-T

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Jan 3, 2006 to Oct 2, 2026

Model Insight

Volatility shocks decay with a half-life of 13 trading days, meaning a shock loses half its impact after approximately 13 days. Returns follow a Student-t distribution with v = 5.62 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 13-day half-lifev = 5.62 · fat tails
ParamValuet-stat
ωconst216.1380
2.51**
αARCH0.1194
5.19***
βGARCH0.9491
45.00***
νDF5.6201
1.62

0.949

Persistence

13d

Half-life
𝑓

GAS-GARCH-T Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

216.1380
2.51**
α

ARCH

Response to squared shocks

0.1194
5.19***
β

GARCH

Volatility persistence

0.9491
45.00***
ν

DF

Student-t tail thickness

5.6201
1.62

Persistence:

0.949

Half-life:

13 days