Table 2. Unstandardized mean differences between conditions and effect sizes D.

Comparison	Preimagery		Postimagery		Post minus pre
	ESum	D	ESum	D	ESum	D
Misses (0 points)
Mastery vs. Performance	–	0.05	–	0.26	–	0.27
Mastery vs. Dual goal	0.71	0.27	1.21	0.45	0.50	0.25
Performance vs. Dual goal	0.85	0.32	1.89	0.71	1.05	0.51
Hit service box (1 point)
Mastery vs. Performance	–	0.05	0.68	0.26	0.82	0.34
Mastery vs. Dual goal	–	0.32	–	0.66	–	0.36
Performance vs. Dual goal	–	0.27	–	0.92	–	0.70
Hit target (2 points)
Mastery vs. Performance	0.27	0.20	0.05	0.03	–	0.14
Mastery vs. Dual goal	0.21	0.16	0.57	0.38	0.36	0.22
Performance vs. Dual goal	–	0.04	0.53	0.35	0.59	0.36