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V-Lab

State Street SPDR S&P Biotech ETF GJR-GARCH Volatility Analysis

Volatility prediction for Tuesday, August 25th, 2026

1 Day

30.62%

decreased by 0.63%

1 Week

30.63%

decreased by 0.62%

1 Month

30.68%

decreased by 0.57%

Analysis last updated: Monday, August 24, 2026 at 09:48 PM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of State Street SPDR S&P Biotech ETF GJR-GARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Feb 6, 2006 to Aug 21, 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

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.0764
15.79***
α

ARCH

Response to squared shocks

0.0163
7.34***
β

GARCH

Volatility persistence

0.9136
357.30***
γ

leverage

Additional response to negative shocks

0.1000
15.86***

Persistence:

0.980

Half-life:

34 days