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V-Lab

Borsa Istanbul 100 Index GJR-GARCH Volatility Analysis

Volatility prediction for Monday, July 27th, 2026

1 Day

22.82%

decreased by 0.24%

1 Week

23.22%

increased by 0.16%

1 Month

24.76%

increased by 1.70%

Analysis last updated: Friday, July 24, 2026 at 04:05 PM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

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graph of Borsa Istanbul 100 Index GJR-GARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Jan 1, 1990 to Jul 24, 2026

Model Insight

With persistence 0.997, volatility shocks have a half-life of 262 trading days (~1.0 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate.

σ

GJR-GARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.0428
17.20***
α

ARCH

Response to squared shocks

0.0671
15.99***
β

GARCH

Volatility persistence

0.9250
400.43***
γ

leverage

Additional response to negative shocks

0.0104
1.41

Persistence:

0.997

Half-life:

262 days