Group                
Depression
scores                               
Mean              
Variance

1
(Placebo)        
32   37   36   37  
33  
35                    
35.0                       
4.4          

2
(Elavil)           
27   33   34   33  
35  
30                    
32.0                       
8.8

3
(Prozac)          
28   25   26   29  
32  
28                    
28.0                       
6.0

4
(Tofranil)        
31   29   35   30  
32  
29                    
31.0                       
5.2

5
(Zoloft)          
26   25   19   23  
25  
26                    
24.0                       
7.2

Overall                                                                               
30.0                      
19.9

Assuming that higher scores indicate greater depression
set up a linear contrast to compare the average of the four drugs
to the placebo.