Table 3.

Multilevel Model Parameter Estimates of Processing Speed Predicting 2-Back Performance.

Fixed Effects	Model 1	Model 2
	Estimate (SE)	Estimate (SE)
Intercept
Young	1190.02 (138.44)**	693.73 (238.81)**
Old	1349.60 (243.63)**	744.73 (207.98)**
Difference	−159.57 (280.22)	−.50.99 (316.68)
Processing Speed (WP)
Young	.11 (.05)*	.09 (.05)
Old	.04 (.06)	.04 (.06)
Difference	.07 (.08)	.05 (.08)
Processing Speed (BP)
Young	.21 (.08)**	.14 (.09)
Old	.33 (.08)**	−.02 (.08)
Difference	−.12 (.12)	.16 (.12)
1-Back (WP)
Young	-	.33 (.15)*
Old	-	.38 (.08)**
Difference	-	−.04 (.17)
1-Back (BP)
Young	-	1.01 (.45)*
Old	-	1.39 (.17)**
Difference	-	−.38 (.48)

Note:

⁺p < .10,

^*p < .05,

^**p < .01.

WP: Within-Person, BP: Between-Person.