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V-Lab
V-Lab

S&P 100 Index Asy. MEM Volatility Analysis

Volatility prediction for Friday, September 18th, 2026

1 Day

12.65%

decreased by 1.09%

1 Week

12.83%

decreased by 0.91%

1 Month

13.47%

decreased by 0.27%

Analysis last updated: Friday, September 18, 2026 at 12:05 AM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of S&P 100 Index AMEM

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Jan 1, 1990 to Sep 11, 2026

Model Insight

This asset exhibits a strong leverage effect: negative returns increase next-day volatility 175% more than equivalent positive returns.

μ

AMEM Model

Tap to view equation

Leverage: Negative returns increase volatility 175% more than positive returns
ParamValuet-stat
ωconst0.0224
9.20***
αARCH0.0993
6.18***
βGARCH0.7934
75.27***
γleverage0.1743
6.18***

0.980

Persistence

34d

Half-life
μ

AMEM Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.0224
9.20***
α

ARCH

Response to squared shocks

0.0993
6.18***
β

GARCH

Volatility persistence

0.7934
75.27***
γ

leverage

Additional response to negative shocks

0.1743
6.18***

Persistence:

0.980

Half-life:

34 days