mbend: Data, Code & Results

R package mbend bends symmetric non-positive-definite matrices to symmetric positive definite matrices. A 5×5 non-positive-definite covariance matrix, its conversion to a correlation matrix, a 5×5 weight matrix for weighted bending, and an ill-conditioned genomic relationship matrix (created by method 1 of VanRaden, 2008) of 5,000 SNP and 1,000 animals with 10 duplicated genotypes and no quality control were used as data.

Weighted and unweighted bending methods of Jorjani et al. (2003) and Schaeffer (2014) were tested and compared with the method of Bock et al. (1988) that is implemented in R package psych.