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V-Lab

Russell Midcap Index APARCH Volatility Analysis

Volatility prediction for Friday, September 4th, 2026

1 Day

13.82%

decreased by 0.68%

1 Week

14.06%

decreased by 0.44%

1 Month

14.88%

increased by 0.38%

Analysis last updated: Friday, September 4, 2026 at 11:25 PM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of Russell Midcap Index APARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Mar 1, 2004 to Aug 27, 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. The volatility power δ = 1.20 sits below 2, so large shocks influence volatility less than quadratically, a more outlier-robust response than standard GARCH.

σ

APARCH Model

Tap to view equation

Leverage: volatility responds almost entirely to negative shocksδ = 1.20 · sub-quadratic power
ParamValuet-stat
ωconst0.0272
7.62***
αARCH0.0757
5.50***
βGARCH0.9095
101.67***
γleverage0.9206
4.23***
δpower1.2018
9.41***

0.978

Persistence

32d

Half-life
σ

APARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.0272
7.62***
α

ARCH

Response to squared shocks

0.0757
5.50***
β

GARCH

Volatility persistence

0.9095
101.67***
γ

leverage

Additional response to negative shocks

0.9206
4.23***
δ

power

Transformation power

1.2018
9.41***

Persistence:

0.978

Half-life:

32 days