Pearson correlation coefficient ( r ) = Σ [ ( X - My )( Y - Mx ) ] / √ [ ( SSx )( SSy ) ]
Where,
SSx = Σ ( X - Mx ) 2
SSy = Σ ( Y - My ) 2
X = X Values
Y = Y Values
Mx = Mean of x values
My = Mean of y values
Σ ( X - Mx ) , Σ ( Y - My ) = Sum of deviation scores
Σ ( X - Mx )2 , Σ ( Y - My )2 = Sum of deviation squared
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