question number 3. determine the correlation coefficient for the data shown in this table: \n| y | x…

question number 3. determine the correlation coefficient for the data shown in this table: \n| y | x |\n|----|----| \n| 22 | 2 |\n| 29 | 4 |\n| 28 | 10 |\n| 40 | 15 |\n| 34 | 13 |\n| 43 | 16 |\no 0.8332\no 0.4564\no -0.9128\no 0.9128\no -0.8332\no none of the above

question number 3. determine the correlation coefficient for the data shown in this table: \n| y | x |\n|----|----| \n| 22 | 2 |\n| 29 | 4 |\n| 28 | 10 |\n| 40 | 15 |\n| 34 | 13 |\n| 43 | 16 |\no 0.8332\no 0.4564\no -0.9128\no 0.9128\no -0.8332\no none of the above

Answer

Explanation:

Step1: Recall correlation - coefficient formula

The Pearson correlation coefficient $r$ is given by the formula: [r=\frac{n(\sum xy)-(\sum x)(\sum y)}{\sqrt{[n\sum x^{2}-(\sum x)^{2}][n\sum y^{2}-(\sum y)^{2}]}}] First, calculate the necessary sums: Let $n = 6$.

$y$ $x$ $xy$ $x^{2}$ $y^{2}$
22 2 44 4 484
29 4 116 16 841
28 10 280 100 784
40 15 600 225 1600
34 13 442 169 1156
43 16 688 256 1849

$\sum x=2 + 4+10 + 15+13+16=60$ $\sum y=22 + 29+28+40+34+43=196$ $\sum xy=44 + 116+280+600+442+688=2170$ $\sum x^{2}=4 + 16+100+225+169+256=770$ $\sum y^{2}=484+841+784+1600+1156+1849=6714$

Step2: Substitute into the formula

[n(\sum xy)-(\sum x)(\sum y)=6\times2170-60\times196] [=13020 - 11760=1260]

[n\sum x^{2}-(\sum x)^{2}=6\times770-60^{2}] [=4620 - 3600 = 1020]

[n\sum y^{2}-(\sum y)^{2}=6\times6714-196^{2}] [=40284-38416 = 1868]

[r=\frac{1260}{\sqrt{1020\times1868}}] [=\frac{1260}{\sqrt{1905360}}] [=\frac{1260}{1380.3477}\approx0.9128]

Answer:

0.9128