Table 2.

Estimated effect size, adjusted standard error (SE), z-value and relative variable importance (RVI) estimated by a generalized linear mixed model to determine the effects of session, species and previous success on gazing at the human partner in trials in which the human arrived first at the tray.

	Effect Size	Adj. SE	z value	P	RVI
Prev. success	−2.946469	0.345245	8.534	<0.001	0.94
Session	0.110677	0.039715	2.787	0.005	0.86
Species	−0.677061	0.487824	1.388	0.165	0.52