In: Math
Here is a bivariate data set.
| x | y | 
|---|---|
| 39 | 45 | 
| 43 | 43 | 
| 12 | 48 | 
| 36 | 38 | 
| 29 | 33 | 
| 31 | 31 | 
| 31 | 37 | 
| 20 | 39 | 
| -4 | 51 | 
| 52 | 31 | 
Find the correlation coefficient and report it accurate to four
decimal places.
r =
Solution:
Given:
| x | y | 
| 39 | 45 | 
| 43 | 43 | 
| 12 | 48 | 
| 36 | 38 | 
| 29 | 33 | 
| 31 | 31 | 
| 31 | 37 | 
| 20 | 39 | 
| -4 | 51 | 
| 52 | 31 | 
We have to find the correlation coefficient r

where



Thus we need to make following table:
| x | y | x^2 | y^2 | xy | 
| 39 | 45 | 1521 | 2025 | 1755 | 
| 43 | 43 | 1849 | 1849 | 1849 | 
| 12 | 48 | 144 | 2304 | 576 | 
| 36 | 38 | 1296 | 1444 | 1368 | 
| 29 | 33 | 841 | 1089 | 957 | 
| 31 | 31 | 961 | 961 | 961 | 
| 31 | 37 | 961 | 1369 | 1147 | 
| 20 | 39 | 400 | 1521 | 780 | 
| -4 | 51 | 16 | 2601 | -204 | 
| 52 | 31 | 2704 | 961 | 1612 | 
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Thus












Thus the correlation coefficient r is:





