Skip to main content
V-Lab

Tokyo Stock Exchange Tokyo Stock Price Index TOPIX GAS-GARCH Student T Volatility Analysis

Volatility prediction for Friday, July 24th, 2026

1 Day

21.15%

decreased by 1.13%

1 Week

21.12%

decreased by 1.16%

1 Month

21.01%

decreased by 1.27%

Analysis last updated: Friday, July 24, 2026 at 05:42 PM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of Tokyo Stock Exchange Tokyo Stock Price Index TOPIX GAS-GARCH-T

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Jan 2, 1990 to Jul 17, 2026

Model Insight

Volatility shocks decay with a half-life of 32 trading days, meaning a shock loses half its impact after approximately 32 days. Returns follow a Student-t distribution with v = 6.36 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

1.6542
11.76***
α

ARCH

Response to squared shocks

0.0831
38.65***
β

GARCH

Volatility persistence

0.9785
515.81***
ν

DF

Student-t tail thickness

6.3575
8.14***

Persistence:

0.978

Half-life:

32 days