V-Lab
General Motors Co Spline ILLIQ Liquidity Analysis
Illiquidity prediction for Monday, September 21st, 2026
1 Day
30.03
increased by 0.01
1 Week
29.84
decreased by 0.18
1 Month
29.72
decreased by 0.30
Analysis last updated: Friday, September 18, 2026 at 11:29 PM UTC
News Impact Curve
How returns affect tomorrow's illiquidityIlliquidity Forecast
How illiquidity evolves over timeParameter Estimates
Nov 18, 2010 to Sep 18, 2026Model Insight
With persistence 0.996, illiquidity shocks have a half-life of 161 trading days (~0.6 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate.
μ
ILLIQ-SMEM Model
Tap to view equation
High persistence: persistence 0.996, shock half-life ~161 days
| Param | Value | t-stat |
|---|---|---|
| ωconst | 1.1595 | 7.55*** |
| αARCH | 0.0696 | 10.04*** |
| βGARCH | 0.9261 | 128.32*** |
Spline Coefficients
K=1
| γ1 | -0.0112 | -2.37** |
0.996
Persistence161d
Half-lifeμ
ILLIQ-SMEM Model
Tap to view equation
| Parameter | Value | t-statistic |
|---|---|---|
ω const Unconditional variance weight | 1.1595 | 7.55*** |
α ARCH Response to squared shocks | 0.0696 | 10.04*** |
β GARCH Volatility persistence | 0.9261 | 128.32*** |
Spline Coefficients
K=1
| γ1 | -0.0112 | -2.37** |
Persistence:
0.996
Half-life:
161 days
Other General Motors Co Analyses
Other Spline ILLIQ Analyses on Equities