Skip to main content
V-Lab
V-Lab

Nikkei Stock Average Volatility Index AGARCH Volatility Analysis

Volatility prediction for Monday, September 28th, 2026

1 Day

104.23%

decreased by 5.82%

1 Week

103.86%

decreased by 6.19%

1 Month

102.86%

decreased by 7.19%

Analysis last updated: Friday, October 2, 2026 at 09:43 PM UTC

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

from

09/25/2024

to

09/25/2026

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of Nikkei Stock Average Volatility Index AGARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Jan 3, 1990 to Sep 25, 2026

Model Insight

The news-impact curve is shifted (γ = -3.81) so that positive returns raise next-day volatility more than negative returns of the same size. Volatility rises more after gains than after losses, the reverse of the usual leverage effect and rare among risky assets.

σ

AGARCH Model

Tap to view equation

Asymmetry: positive returns raise volatility more
ParamValuet-stat
ωconst1.1187
1.99**
αARCH0.0995
8.00***
βGARCH0.8373
52.26***
γleverage-3.8096
-4.24***

0.937

Persistence

11d

Half-life
σ

AGARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

1.1187
1.99**
α

ARCH

Response to squared shocks

0.0995
8.00***
β

GARCH

Volatility persistence

0.8373
52.26***
γ

leverage

Additional response to negative shocks

-3.8096
-4.24***

Persistence:

0.937

Half-life:

11 days