Table 3.

Results from mixed effects regression analyses comparing differences in free-play behavior related to generalization (shape vs. material).

	Free-play behavior	Predictor	B	se	t	95% CI	Variance	SD	X2	p	d
Solid objects	Coordinated exploration	Shape vs. Material	0.97	1.97	0.49	−2.78, 4.73	–	–	0.27	0.603	0.16
		Age	0.08	0.20	0.41	−0.29, 0.46	–	–	0.38	0.540	0.14
		Vocabulary	−0.005	0.008	−0.58	−0.02, 0.01	–	–	0.19	0.664	0.19
		Subject Intercept	–	–	–	–	<0.0001	<0.0001	<0.0001	>0.99	–
	Synchronous naming rate	Shape vs. Material	−0.07	0.08	−0.88	−0.24, 0.09	–	–	0.82	0.365	0.31
		Age	−0.01	0.01	−1.07	−0.04, 0.01	–	–	1.40	0.237	0.65
		Vocabulary	0.0005	0.0006	0.95	−0.0005, 0.002	–	–	1.23	0.289	0.57
		Subject Intercept	–	–	–	–	0.04	0.20	5.07	0.024	–
Nonsolid substances	Coordinated exploration	Shape vs. Material	−0.18	1.37	−0.13	−2.79, 2.45	–	–	0.02	0.896	0.05
		Age	0.01	0.15	0.07	−0.28, 0.30	–	–	0.07	0.789	0.13
		Vocabulary	−0.002	0.007	−0.25	−0.01, 0.01	–	–	0.007	0.936	0.04
		Subject Intercept	–	–	–	–	0.34	0.58	0.32	0.573
	Synchronous naming rate	Shape vs. Material	−0.03	0.06	−0.52	−0.16, 0.10	–	–	0.26	0.613	0.20
		Age	−0.002	0.01	−0.17	−0.02, 0.02	–	–	0.03	0.864	0.09
		Vocabulary	0.0004	0.0004	0.87	−0.0004, 0.001	–	–	0.89	0.345	0.45
		Subject Intercept	–	–	–	–	0.01	0.12	1.93	0.165	–