In: Statistics and Probability
Construct a scattergram for each data set. Then calculate r and r 2 for each data set. Interpret their values. Complete parts a through d
a. |
x |
−1 |
0 |
1 |
2 |
3 |
|
---|---|---|---|---|---|---|---|
y |
−3 |
0 |
1 |
4 |
5 |
Calculate r.
r=. 9853 (Round to four decimal places as needed.)
Calculate r2.
r2=0.9709. (Round to four decimal places as needed.)
Interpret r. Choose the correct answer below.
A.There is not enough information to answer this question.
B.There is a very strong negative linear relationship between x and y.
C.x and y are not related.
D.There is a very strong positive linear relationship between x and y. Your answer is correct.
Interpret
r2=97.09% of the total sample variability around y overbary is explained by the linear relationship between x and y.
(Round to two decimal places as needed.)
b. |
x |
−1 |
0 |
1 |
2 |
3 |
|
---|---|---|---|---|---|---|---|
y |
5 |
4 |
2 |
1 |
−1 |
Calculate r.
r=−0.9934 (Round to four decimal places as needed.)
Calculate r2.
r2=. 9868. (Round to four decimal places as needed.)
Interpret r. Choose the correct answer below.
A.There is a very strong negative linear relationship between x and y. Your answer is correct.
B.There is not enough information to answer this question.
C. There is a very strong positive linear relationship between x and y.
D.x and y are not related.
Interpret r2.
98.68% of the total sample variability around y overbary is explained by the linear relationship between x and y.
(Round to two decimal places as needed.)
c. |
x |
1 |
2 |
2 |
3 |
3 |
3 |
4 |
|
---|---|---|---|---|---|---|---|---|---|
y |
2 |
1 |
3 |
1 |
2 |
3 |
2 |
Calculate r.
r=___________(Round to four decimal places as needed.)
Following is the scatter plot:
Following table shows the calculations:
X | Y | X^2 | Y^2 | XY | |
-1 | -3 | 1 | 9 | 3 | |
0 | 0 | 0 | 0 | 0 | |
1 | 1 | 1 | 1 | 1 | |
2 | 4 | 4 | 16 | 8 | |
3 | 5 | 9 | 25 | 15 | |
Total | 5 | 7 | 15 | 51 | 27 |
Sample size: n=5
The coefficient of correlation is :
The coefficient of determination is:
D.There is a very strong positive linear relationship between x and y.
The 97.09% of the total sample variability around y is explained by the linear relationship between x and y.
-----------------------
(b)
Following is the scatter plot:
Following table shows the calculations:
X | Y | X^2 | Y^2 | XY | |
-1 | 5 | 1 | 25 | -5 | |
0 | 4 | 0 | 16 | 0 | |
1 | 2 | 1 | 4 | 2 | |
2 | 1 | 4 | 1 | 2 | |
3 | -1 | 9 | 1 | -3 | |
Total | 5 | 11 | 15 | 47 | -4 |
Sample size: n=5
The coefficient of correlation is :
The coefficient of determination is:
A.There is a very strong negative linear relationship between x and y.
The 98.68% of the total sample variability around y overbary is explained by the linear relationship between x and y.
--------------------------
(c)
Following is the scatter plot:
Following table shows the calculations:
X | Y | X^2 | Y^2 | XY | |
1 | 2 | 1 | 4 | 2 | |
2 | 1 | 4 | 1 | 2 | |
2 | 3 | 4 | 9 | 6 | |
3 | 1 | 9 | 1 | 3 | |
3 | 2 | 9 | 4 | 6 | |
3 | 3 | 9 | 9 | 9 | |
4 | 2 | 16 | 4 | 8 | |
Total | 18 | 14 | 52 | 32 | 36 |
Sample size: n=7
The coefficient of correlation is :
The coefficient of determination is:
x and y are not related.