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x X=→ Ε
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x X=→ Ε
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( )
1, 4x X=→ Ε =
( )
0,9165x n X
σ σ
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( )
4, 2y Y=→ Ε =
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0,9798y n Y
σ σ
=→ =
0,0891
XY
r R=→ = −

( )
5,8xy XY=→ Ε =
∑