The Kinship Matrix
The kinship matrix is a square matrix that contains the pairwise relationship between all represented genotypes. The size of the matrix is , where is the number of genotypes being compared. The values in the matrix range from 0 (no relationship between genotypes) to 1 (identical genotypes). The diagonal represents the relationship between each genotype with itself and is thus only 1's. The matrix is symmetric around the diagonal. The matrix is calculated from a matrix of polymorphisms, , where is the number of genotypes and is the number of markers. The matrix is calculated as follows:
where is the genotype, is the genotype, is a column vector of polymorphisms for the genotype and is a column vector of polymorphisms for the genotype.