Table 2.

Comparison of linear mixed effects models of starting pupil diameter to evaluate the contributions of luminance, encoding condition (target vs. distractor), and their interaction.

Fixed Effects	AIC	Log Likelihood	df	χ 2	p
luminance only	−540.48	274.24	4
luminance + encoding condition	−538.61	274.31	5	0.131	0.718
luminance × encoding condition	−537.67	274.84	6	1.061	0.303

Note: χ² tests compared models that differed in one parameter, and therefore had 1 df.