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Paired Samples T-test Independent Samples T-test Multiple Regression One Way Analysis of Variance

 

PAIRED SAMPLES T-TEST

This example is based on:
Tiggemann, M. & Lynch, J. E. (2001). Body image across the life span in adult women: The role of self-objectification. Developmental Psychology, 37(2), 243-253.

Body dissatisfaction was measured in adult women (n = 322) ranging in age from 20 to 84. Using the Figure Rating Scale, the women were asked to select their current figure and their ideal figure from a series of silhouette drawings. The drawings were numbered from 10-90. Body dissatisfaction is the discrepancy between the ideal and current ratings. The following table lists the means that were compared in the study.

 

Age Group (in years) Current Figure Ideal Figure
     
Entire Sample (n=322)    
M
46.50 36.55
SD
11.44 6.38
     
20-29 (n=75)    
M
44.75 34.65
SD
12.56 6.57
     
30-39 (n=50)    
M
44.50 35.54
SD
10.98 5.78
     
40-49 (n=81)    
M
45.84 35.95
SD
10.37 5.32
     
50-59 (n=43)    
M
47.79 38.05
SD
10.65 6.63
     
60-69 (n=41)    
M
47.93 38.00
SD
11.72 6.77
     
70-85 (n=32)    
M
51.81 40.50
SD
11.34 6.48
     

 

Using the data presented in Tiggemann & Lynch's study, we will perform a power analysis.