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skysophie

Definitions.-An arrangement of v objects (called treatments) in b sets
(called blocks) will be called a pairwise balanced design of index unity and type
8 C8 r* A2 l4 v2 P8 R(v; ki, k2, .. ., ki) if each block contains either k1, k2, .. ., or km treatments which
are all distinct (k, < v, k, $ kj), and every pair of distinct treatments occurs exactly
in one block of the design. If the number of blocks containing k, treatments is
5 @" i4 ]  Z1 J5 S' f0 B7 |b,, then clearly  b = A bi, v(v-1) = i biki(k -1)。。。
- }# d& n, m* a/ P1 R! {! k3 j
2 ]% W8 ]& l5 C7 o谁能帮我解释一下，可以举个简单的例子。。谢谢！~

角凳

是告诉我们这是哪个领域的么？？