Figure 4From: Use of a multi-way method to analyze the amino acid composition of a conserved group of orthologous proteins in prokaryotesThe 3-way Tucker3 model. The Tucker3 algorithm decomposes a three-dimensional matrix, X, into a matrix of residuals, E, three component matrices A, B, C called loadings matrices, and a 3-way core array, G. The X matrix of order (20 × 64 × 62) is the input of the algorithm and contains the frequency with which amino acid is used in each group of orthologous proteins and in each organism. The loadings matrices A, B and C are similar to the scores or loadings matrices in standard PCA and contain the projections of the X matrix in the representative principal factors. The core array, G, defines how the individual loadings vectors interact. See the Methods section and reference [43] for more details about the Tucker3 model.Back to article page