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Overlapping design matrices

If you have problems overlapping design matrices when using the and operator (as in the equivalent models) section, in an email Arthur Gilmour explains:

… for ‘male and(female)’ to correctly overlay the male design matrix with the female design matrix, the columns must correspond which means that the ith ‘male’ must be the same individual as the ith ‘female’.

 female !I
 male   !I

is most unlikely to achieve this (unless the initial N lines in the data file referred to the selfing of all N individuals). Assuming N was 30 (26 appearing as males and 22 appearing as females) female 20 male 20 would achieve the desired effect if the individuals are conformably coded 1…30 in these fields of data file.

Otherwise, create a ‘pedigree file’ which lists the (30) individuals (parents); e.g.

 40245 0 0
 52645 0 0

and then use

 female !P 
 male   !P

so they are coded conformably.

Copyright (1997–2021) by Luis Apiolaza, some rights are reserved.

Updated on September 23, 2021

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