Case Study 7.1: The Flick Tail Study 
------------------------------------------------------------------
Variables: 

     OBS          Index number  
     SET          One of four possible dose combinations 
     MORPHINE     Dose of morphine sulfate (mg/kg) injected  
                    into study mice.  The range is 0 to 8.0 
     DEL9         Dose of Delta9-THC (mg/kg) injected into  
                    study mice.  The range is from 0 to 16 
     FLICK        The number of mice that flick the tail after 
                     being applied a heat stimulus from beneath 
     REPS         Number of repetitions (with different mice)  
     PROP         Proportion of flicks = FLICK/REPS  

------------------------------------------------------------------
c71.dat:

obs  set  morphine  del9  flick  reps  prop
 1     O       0.0   0.0      0    10   0.0
 2     A       1.0   0.0      0    10   0.0
 3     A       2.0   0.0      2    10   0.2
 4     A       3.0   0.0      4    10   0.4
 5     A       4.0   0.0      4    10   0.4
 6     A       5.0   0.0      6    10   0.6
 7     A       6.0   0.0      9    10   0.9
 8     A       7.0   0.0      9    10   0.9
 9     A       8.0   0.0      8    10   0.8 
10     B       0.0   1.0      0    10   0.0
11     B       0.0   2.0      0    10   0.0
12     B       0.0   4.0      9    10   0.9
13     B       0.0   8.0      9    10   0.9
14     B       0.0  16.0     10    10   1.0
15    AB       0.5   0.5      0    10   0.0
16    AB       1.0   1.0      2    10   0.2
17    AB       1.5   1.5      7    10   0.7
18    AB       2.0   2.0      9    10   0.9
19    AB       2.5   2.5      9    10   0.9
20    AB       3.0   3.0      9    10   0.9