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V-Lab

S&P 1000 Index GAS-GARCH Student T Volatility Analysis

Volatility prediction for Wednesday, August 19th, 2026

1 Day

14.45%

increased by 1.90%

1 Week

14.62%

increased by 2.07%

1 Month

15.23%

increased by 2.68%

Analysis last updated: Tuesday, August 18, 2026 at 11:06 PM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of S&P 1000 Index GAS-GARCH-T

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Dec 29, 1994 to Aug 14, 2026

Model Insight

Volatility shocks decay with a half-life of 46 trading days, meaning a shock loses half its impact after approximately 46 days. Returns follow a Student-t distribution with v = 12.17 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

1.5011
12.28***
α

ARCH

Response to squared shocks

0.0917
33.86***
β

GARCH

Volatility persistence

0.9851
686.48***
ν

DF

Student-t tail thickness

12.1675
3.79***

Persistence:

0.985

Half-life:

46 days