Statistical Methods for Psychology

484 Chapter 14 Repeated-Measures Designs

Table 14.7 Data and analysis of study by St. Lawrence et al. (1995)

(a) Data

Male Female
Pretest Posttest FU6 FU12 Pretest Posttest FU6 FU12
7 221314 0 62226
25 10 17 24 0 16 12 15
Behavioral 50 36 49 23 0 8 0 0
Skill 16 38 34 24 15 14 22 8
Training 33 25 24 25 27 18 24 37
10 7 23 26 0 0 0 0
13 33 27 24 4 27 21 3
22 20 21 11 26 9 9 12
4012000141
17 16 20 10 0 0 12 0

0 0 0 0 15 28 26 15
69 56 14 36 0 0 0 0
500560230
4 24000 000
Educational 35 80025 28016
Control 7 0 937 36 22 1448
51 53 8 26 19 22 29 2
25 0 0 15 0 0 5 14
59 45 11 16 0 0 0 0
40 2 33 16 0 0 0 0

Group 3 Sex 3 Time means

Pretest Posttest FU6 FU12 Mean

BST Male 19.7 20.7 24.0 18.1 20.625
BST Female 7.2 9.8 13.6 10.2 10.200
EC Male 29.5 18.8 7.5 15.1 17.725
EC Female 10.1 10.0 9.7 9.5 9.825
Mean 16.625 14.825 13.700 13.225 14.594

Group 3 Sex means

Male Female Mean

BST 20.625 10.200 15.412
EC 17.725 9.825 13.775
Mean 19.175 10.012 14.594

(b) Calculations

SSSex=ntga(XSex 2 X)^2 = 1034323 (19.175 2 14.594)^21 (10.012 2 14.594)^24 =3358.056

SSgroup=ntsa(XG 2 X)^2 = 1034323 (15.412 2 14.594)^21 (13.775 2 14.594)^24 =107.256

SSsubj=ta(XSubj 2 X)^2 = 43 (14 2 14.594)^2 1 Á 1 (0 2 14.594)^24 =21490.344

SStotal= a(X 2 X)^2 =(7 2 14.594)^2 1 Á 1 (0 2 14.594)^2 =35404.594

(continues)