# Question: In a random sample of n pairs of values of

In a random sample of n pairs of values of X and Y, (xi, yj) occurs fij times for i = 1, 2, . . . , r and j = 1, 2, . . . , c. Letting fi, denote the number of pairs where X takes on the value xi and fj the number of pairs where Y takes on the value yj, write a formula for the coefficient of correlation.

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