probability - How to generate multiple unrepeated random variables with a fixed non-uniform distribution? -
so given discrete distribution, (0.2, 0.4, 0.4), easy generate 1 random number follow distribution.
however, generate multiple unrepeated random numbers it?
e.g. distribution (p1 = 0.2, p2 = 0.4, p3 = 0.4), if generate
(1,2) p12 = 0.2,
(2,3) p23 = 0.6,
(1,3) p13 = 0.2.
i'm able have marginal distribution of
p1 = (p12 + p13)/2 = 0.2,
p2 = (p23 + p12)/2 = 0.4,
p3 = (p13 + p23)/2 = 0.4.
which same given distribution.
any idea build generator accomplish in terms of general distribution? thanks:)
if @ problem set of linear equations, able express using matrix equation. instance:
|1/2 1/2 0 | |p12| |p1| |1/2 0 1/2| * |p13| = |p2| | 0 1/2 1/2| |p23| |p3|
now can invert matrix get:
|p12| | 1 1 -1| |p1| |p13| = | 1 -1 1| * |p2| |p23| |-1 1 1| |p3|
in example produce:
|p12| | 1 1 -1| |0.2| |0.2| |p13| = | 1 -1 1| * |0.4| = |0.2| |p23| |-1 1 1| |0.4| |0.6|
so, p12 = p13 = 0.2
, p23 = 0.6
.
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