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V-Lab

Global X S&P 500 Christin VL GAS-GARCH Student T Volatility Analysis

Volatility prediction for Tuesday, July 21st, 2026

1 Day

12.98%

decreased by 0.19%

1 Week

13.12%

decreased by 0.05%

1 Month

13.38%

increased by 0.21%

Analysis last updated: Monday, July 20, 2026 at 09:27 PM UTC

Date Range:

from

to

6M ·

All

graph of Global X S&P 500 Christin VL GAS-GARCH-T

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Sep 24, 2025 to Jul 17, 2026

Model Insight

Volatility shocks decay with a half-life of 5 trading days, meaning a shock loses half its impact after approximately 5 days. Returns follow a Student-t distribution with v = 7.96 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

0.7326
4.42***
α

ARCH

Response to squared shocks

0.0298
1.02
β

GARCH

Volatility persistence

0.8715
5.82***
ν

DF

Student-t tail thickness

7.9573
0.11

Persistence:

0.872

Half-life:

5 days