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V-Lab

S&P 500 Scored & Screened Index (ESG) APARCH Volatility Analysis

Volatility prediction for Thursday, August 20th, 2026

1 Day

11.68%

decreased by 0.85%

1 Week

12.14%

decreased by 0.39%

1 Month

13.72%

increased by 1.19%

Analysis last updated: Wednesday, August 19, 2026 at 11:07 PM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

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10Y ·

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graph of S&P 500 Scored & Screened Index (ESG) APARCH

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Apr 28, 2005 to Aug 14, 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 = 0.92 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

ParameterValuet-statistic
ω

const

Unconditional variance weight

0.0365
27.00***
α

ARCH

Response to squared shocks

0.1045
19.69***
β

GARCH

Volatility persistence

0.8907
179.54***
γ

leverage

Additional response to negative shocks

0.9272
12.41***
δ

power

Transformation power

0.9157
25.02***

Persistence:

0.970

Half-life:

23 days