pair.no vasectomy obesity smoking mi    
 1  1   0   0   0
 1  0   1   0   1
 2  1   1   0   1
 2  0   0   1   0
 3  1   0   1   1
 3  0   0   0   0
 4  1   0   1   0
 4  0   0   1   1
 5  1   1   0   0
 5  0   1   1   1
 6  1   0   0   1
 6  0   0   1   0
 7  1   1   0   1
 7  0   0   1   0
 8  1   0   0   1
 8  0   0   0   0
 9  1   0   0   0
 9  0   0   1   1
10  1   0   1   1
10  0   0   1   0
11  1   0   1   0
11  0   0   1   1
12  1   0   0   0
12  0   0   0   1
13  1   1   1   1
13  0   0   1   0
14  1   0   0   0
14  0   0   1   1
15  1   0   1   1
15  0   0   0   0
16  1   1   1   1
16  0   1   1   0
17  1   0   0   1
17  0   0   0   0
18  1   1   1   0
18  0   0   1   1
19  1   1   1   1
19  0   0   0   0
20  1   0   0   0
20  0   0   1   1
21  1   0   0   0
21  0   0   1   1
22  1   0   1   0
22  0   0   0   1
23  1   0   1   1
23  0   0   1   0
24  1   0   1   1
24  0   0   0   0
25  1   1   1   1
25  0   0   0   0
26  1   0   0   0
26  0   0   0   1
27  1   0   1   1
27  0   0   1   0
28  1   1   0   1
28  0   0   0   0
29  1   0   0   0
29  0   0   1   1
30  1   0   0   1
30  0   0   0   0
31  1   0   1   0
31  0   1   1   1
32  1   0   1   1
32  0   0   0   0
33  1   1   0   0
33  0   0   0   1
34  1   1   0   0
34  0   0   1   1
35  1   0   0   1
35  0   0   0   0
36  1   0   0   1
36  0   0   0   0