Table 1.

The statistical results of the three regression models testing absolute residuals from a linear regression (Model 1.1).

Model	Estimate	t value	P value	AIC	Comment
Model 2.1: Simple linear regression	0.0145	2.473	0.015	373.5	Failed to measure inter-individual correlation
Model 2.2: Mixed model of random intercept and slope	0.0122	2.982	0.006	278.1	Poor statistical power
Model 2.3: Mixed model of random intercept	0.0139	4.097	8.31 × 10−05	293.5	Selected model