Definitions.-An arrangement of v objects (called treatments) in b sets $ Z6 Y9 E& D4 {4 q/ L: h# a# s9 }3 J" U(called blocks) will be called a pairwise balanced design of index unity and type4 R1 W9 i0 u, J+ U* H# \
(v; ki, k2, .. ., ki) if each block contains either k1, k2, .. ., or km treatments which8 y S3 e; E* T3 g) |" n, M
are all distinct (k, < v, k, $ kj), and every pair of distinct treatments occurs exactly 6 K- ]( W' y! u3 g$ i" D+ @7 |0 p5 u( Nin one block of the design. If the number of blocks containing k, treatments is Q) M& _$ b( }9 O
b,, then clearly b = A bi, v(v-1) = i biki(k -1)。。。 + V5 i& n4 e+ I. S: q ! W- P, b) C: F! ? U4 T谁能帮我解释一下,可以举个简单的例子。。谢谢!~) g! O$ h) _9 O: n) F. B