Pearson’s Sample Correlation Coefficient,
r
= the sum
n
= number of paired items
x
i
= input variable
y
i
= output variable
x
= x-bar = mean of
x
’s
y
= y-bar = mean of
y
’s
s
x
= standard deviation of
x
’s
s
y
= standard deviation of
y
’s
Return to By-Hand Procedures
= the sum