Skip to main content
V-Lab
V-Lab

S&P 500 Equal Weight Index (EWI) GJR-GARCH Volatility Analysis

Volatility prediction for Monday, October 12th, 2026

1 Day

10.99%

decreased by 0.32%

1 Week

11.24%

decreased by 0.07%

1 Month

12.10%

increased by 0.79%

Analysis last updated: Saturday, October 10, 2026 at 02:26 AM UTC

Press Delete or Backspace to remove this series.
Date Range:

from

10/09/2024

to

10/09/2026

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of S&P 500 Equal Weight Index (EWI) GJR-GARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Jan 1, 1990 to Oct 9, 2026

Model Insight

This asset exhibits a strong leverage effect: volatility responds almost entirely to negative shocks. The ARCH response to positive shocks is negligible.

σ

GJR-GARCH Model

Tap to view equation

Leverage: volatility responds almost entirely to negative shocks
ParamValuet-stat
ωconst0.0186
5.57***
αARCH0.0175
2.07**
βGARCH0.8987
122.79***
γleverage0.1369
6.77***

0.985

Persistence

45d

Half-life
σ

GJR-GARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.0186
5.57***
α

ARCH

Response to squared shocks

0.0175
2.07**
β

GARCH

Volatility persistence

0.8987
122.79***
γ

leverage

Additional response to negative shocks

0.1369
6.77***

Persistence:

0.985

Half-life:

45 days