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Miklós Schweitzer
1975 Miklós Schweitzer
11
11
Part of
1975 Miklós Schweitzer
Problems
(1)
Miklos Schweitzer 1975_11
Source: Shannon entropy
12/30/2008
Let
X
1
,
X
2
,
.
.
.
,
X
n
X_1,X_2,...,X_n
X
1
,
X
2
,
...
,
X
n
be (not necessary independent) discrete random variables. Prove that there exist at least
n
2
/
2
n^2/2
n
2
/2
pairs
(
i
,
j
)
(i,j)
(
i
,
j
)
such that H(X_i\plus{}X_j) \geq \frac 13 \min_{1 \leq k \leq n} \{ H(X_k) \}, where
H
(
X
)
H(X)
H
(
X
)
denotes the Shannon entropy of
X
X
X
. GY. Katona
probability and stats