Abstract: | In this note it is shown that the block design with incidence matrix Ñ = NN… N], where N = c1hNh + coh (11′–Nh). coh and c1h are any non-negative integers and Nh,h = 1, 2,…,p, are incidence matrices of balanced incomplete block designs with the same number of treatments t, is a balanced block design with the block sizes exceeding the number of treatments. In derivation the matrix M0, introduced by CALIński (1971) is utilized. |