Regression Using Certain Direct Product Matrices (Algorithm 366 [G2]) CACM December, 1969 Claringbold, P. J. analysis of variance, analysis of covariance, regression analysis, experimental design, matrix direct product, protection operator, orthogonal matrix 5.14 5.5 CA691210 JB February 15, 1978 2:23 PM 1801 5 1802 1802 5 1802 1802 5 1802 1802 5 1802 1802 6 1802