!  Ann. Hum. Genet., Lond. (1979), 42, 507                                  
!  Printed in Great Britain                                                 
!                                                                           
!        The 'singles' method for segregation analysis under                
!                      incomplete ascertainment                             
!                                                                           
!                          by A. M. Davie                                   
!                                                                           
!                        ^  R - J                                           
!   Our estimate of p is p = ----- where R = total number of affected sibs, 
!                           T - J                                           
!  T = total number of siblings, J = number of sibships with only one       
!  proband ('singles').  For large samples the variance of our estimate can 
!  be estimated by                                                          
!                                                                           
!          ^    (R - J)(T - R)    2Q(T - R)**2                              
!     var (p) ~ --------------  + ------------                              
!                 (T - J)**3       (T - J)**4                               
!                                                                           
!  where Q is the number of sibships containing exactly two probands.       
!                                                                           
!   To illustrate the use of the method we take an example from Emery       
!  (1976), p. 49, of ten sibships with phenylketonuria.                     
!                                                                           
1 1 x x m n n
1 2 x x f n n
1 3 1 2 f y y
1 4 1 2 f n n
1 5 1 2 f n n
1 6 1 2 f n n
2 1 x x m n n
2 2 x x f n n
2 3 1 2 f y y
2 4 1 2 f y n
2 5 1 2 f n n
3 1 x x m n n
3 2 x x f n n
3 3 1 2 f y y
3 4 1 2 f n n
3 5 1 2 f n n
4 1 x x m n n
4 2 x x f n n
4 3 1 2 f y y
4 4 1 2 f y n
4 5 1 2 f n n
4 6 1 2 f n n
4 7 1 2 f n n
5 1 x x m n n
5 2 x x f n n
5 3 1 2 f y y
5 4 1 2 f y y
5 5 1 2 f n n
5 6 1 2 f n n
5 7 1 2 f n n
6 1 x x m n n
6 2 x x f n n
6 3 1 2 f y y
6 4 1 2 f y n
7 1 x x m n n
7 2 x x f n n
7 3 1 2 f y y
7 4 1 2 f y n
7 5 1 2 f n n
7 6 1 2 f n n
7 7 1 2 f n n
8 1 x x m n n
8 2 x x f n n
8 3 1 2 f y y
8 4 1 2 f n n
8 5 1 2 f n n
8 6 1 2 f n n
9 1 x x m n n
9 2 x x f n n
9 3 1 2 f y y
9 4 1 2 f n n
10 1 x x m n n
10 2 x x f n n
10 3 1 2 f y y
10 4 1 2 f y y
10 5 1 2 f n n
! end-of-pedigrees