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V-Lab

Straits Times Index STI Spline-GARCH Volatility Analysis

Volatility prediction for Monday, September 14th, 2026

1 Day

10.57%

decreased by 0.57%

1 Week

10.94%

decreased by 0.20%

1 Month

11.97%

increased by 0.83%

Analysis last updated: Friday, September 11, 2026 at 10:04 AM UTC

Date Range:

from

to

6M ·

1Y ·

2Y ·

5Y ·

10Y ·

All

graph of Straits Times Index STI SGARCH

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 model fits a time-varying baseline (a spline), so volatility mean-reverts toward a slowly-shifting long-run level rather than a constant. Short-run deviations decay with a half-life of 13 trading days.

τ

Spline-GARCH Model

Tap to view equation

Time-varying baseline: volatility reverts to a slowly-shifting spline trend
ParamValuet-stat
ωconst1.1461
4.91***
αARCH0.1332
8.36***
βGARCH0.8147
43.61***
γi Spline Coefficients
K=9
γ1-0.0256
-0.64
γ20.1150
2.00**
γ3-0.2264
-6.05***
γ40.2609
7.40***
γ5-0.2196
-5.78***
γ60.1430
3.87***
γ7-0.0324
-0.91
γ8-0.0490
-1.28
γ90.0703
1.31

0.948

Persistence

13d

Half-life
τ

Spline-GARCH Model

Tap to view equation

ParameterValuet-statistic
ω

const

Unconditional variance weight

1.1461
4.91***
α

ARCH

Response to squared shocks

0.1332
8.36***
β

GARCH

Volatility persistence

0.8147
43.61***
γi Spline Coefficients
K=9
γ1-0.0256
-0.64
γ20.1150
2.00**
γ3-0.2264
-6.05***
γ40.2609
7.40***
γ5-0.2196
-5.78***
γ60.1430
3.87***
γ7-0.0324
-0.91
γ8-0.0490
-1.28
γ90.0703
1.31

Persistence:

0.948

Half-life:

13 days