Table 2.

Means and Standard Deviations (in parentheses) for Primary Measures as a Function of Age

Measure	18 months	24 months
Sharing
Sharing score (0 – 5)	1.56 (1.05)	3.24 (1.26)
Proportion Trials Shared Immediately	.08 (.12)	.34 (.29)
Proportion Trials Shared Before Verbal Request	.28 (.27)	.73 (.30)
Proportion Trials Ever Shared (including after verbal request or demonstration)	.53 (.31)	.81 (.26)
Non-Sharing Behavior
Hypothesis-test (freq)	7.88 (4.0)	5.20 (4.1)
Self-focused (freq)	5.23 (4.7)	2.08 (3.8)
Refusals (freq)	1.85 (2.9)	.84 (1.8)
Self-Other Understanding
Self-understanding (0 – 48)	18.32 (5.6)	29.8 (9.9)
Ownership Understanding (proportion correct)	.56 (.25)	.84 (.18)