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V-Lab

Proshares S&P 500 EX-Technology ETF GAS-GARCH Student T Volatility Analysis

Volatility prediction for Monday, August 17th, 2026

1 Day

763.74%

decreased by 96.28%

1 Week

761.94%

decreased by 98.08%

1 Month

754.80%

decreased by 105.22%

Analysis last updated: Saturday, August 15, 2026 at 02:34 AM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of Proshares S&P 500 EX-Technology ETF GAS-GARCH-T

News Impact Curve

How returns affect tomorrow's volatility

Volatility Forecast

How volatility evolves over time

Parameter Estimates

Sep 24, 2015 to Aug 14, 2026
Extended Optimization

Model Insight

The estimated Student-t degrees of freedom v = 2.00 sit at the infinite-variance boundary (v → 2): the model is attributing extreme moves to heavy tails rather than to volatility, so the volatility scale is unreliable here. See the boundary-parameters flag.

𝑓

GAS-GARCH-T Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

11.5686
15.30***
α

ARCH

Response to squared shocks

0.0925
131.83***
β

GARCH

Volatility persistence

0.9976
6,196.43***
ν

DF

Student-t tail thickness

2.0002

Persistence:

0.998

Half-life:

292 days