In: Statistics and Probability
The data in the accompanying table represent the heights and weights of a random sample of professional baseball players. Complete parts (a) through (c) below.
Player |
Height (inches) |
Weight (pounds) |
|
---|---|---|---|
Player 1 |
75 |
225 |
|
Player 2 |
75 |
197 |
|
Player 3 |
72 |
180 |
|
Player 4 |
82 |
231 |
|
Player 5 |
69 |
185 |
|
Player 6 |
7474 |
190190 |
|
Player 7 |
75 |
228 |
|
Player 8 |
71 |
200 |
|
Player 9 | 75 | 230 | |
(a) Draw a scatter diagram of the data, treating height as the explanatory variable and weight as the response variable. Choose the correct graph below.
(b) Determine the least-squares regression line. Test whether there is a linear relation between height and weight at the
alphaαequals=0.05
level of significance.
Determine the least-squares regression line. Choose the correct answer below.
A.
ModifyingAbove y with caretyequals=8.0588.058xnegative 93.9−93.9
B.
ModifyingAbove y with caretyequals=negative 93.9−93.9xplus+4.0584.058
C.
ModifyingAbove y with caretyequals=4.0584.058xnegative 93.9−93.9
D.
ModifyingAbove y with caretyequals=4.0584.058xnegative 95.9
Test whether there is a linear relation between height and weight at the
alphaαequals=0.05
level of significance.
State the null and alternative hypotheses. Choose the correct answer below.
A.
Upper H 0H0:
beta 0β0equals=0
Upper H 1H1:
beta 0β0not equals≠0
B.
Upper H 0H0:
beta 1β1equals=0
Upper H 1H1:
beta 1β1greater than>0
C.
Upper H 0H0:
beta 1β1equals=0
Upper H 1H1:
beta 1β1not equals≠0
D.
Upper H 0H0:
beta 0β0equals=0
Upper H 1H1:
beta 0β0greater than>0
Determine the P-value for this hypothesis test.
P-valueequals=nothing
(Round to three decimal places as needed.) State the appropriate conclusion at the
alphaαequals=0.05
level of significance. Choose the correct answer below.
A.Reject
Upper H 0H0.
There is sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
B.Do not reject
Upper H 0H0.
There is not sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
C.Reject
Upper H 0H0.
There is not sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
D.Do not reject
Upper H 0H0.
There is sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
(c) Remove the values listed for Player 4 from the data table. Test whether there is a linear relation between height and weight. Do you think that Player 4 is influential?
Determine the P-value for this hypothesis test.
P-valueequals=nothing
(Round to three decimal places as needed.) State the appropriate conclusion at the
alphaαequals=0.05
level of significance. Choose the correct answer below.
A.Do not reject
Upper H 0H0.
There is sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
B.Reject
Upper H 0H0.
There is sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
C.Do not reject
Upper H 0H0.
There is not sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
D.Reject
Upper H 0H0.
There is not sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
Do you think that Player 4 is influential?
No
Yes
Click to select your answer(s).
a)
Scatter plot gives an insight of positive relation between weight and height.
b)
Player | Height (inches) xi | Weight (pounds) yi | xi^2 | yi^2 | xi*yi |
Player 1 | 75 | 225 | 5625 | 50625 | 16875 |
Player 2 | 75 | 197 | 5625 | 38809 | 14775 |
Player 3 | 72 | 180 | 5184 | 32400 | 12960 |
Player 4 | 82 | 231 | 6724 | 53361 | 18942 |
Player 5 | 69 | 185 | 4761 | 34225 | 12765 |
Player 6 | 74 | 190 | 5476 | 36100 | 14060 |
Player 7 | 75 | 228 | 5625 | 51984 | 17100 |
Player 8 | 71 | 200 | 5041 | 40000 | 14200 |
Player 9 | 75 | 230 | 5625 | 52900 | 17250 |
Sum | 668 | 1866 | 49686 | 390404 | 138927 |
Average | 74.22222 | 207.3333 |
Sxx = 105.56
Syy = 3520
Sxy = 428.33
b1 = Sxy/ Sxx = 4.058
b0 = 207.33 - 4.058*74.22 = -93.261
equation => Y = -93.9 + 4.058 X
Test for significance
H0:β1 = 0
H1:β1 ≠ 0
ANOVA | |||||
df | SS | MS | F | Significance F | |
Regression | 1 | 1738.132 | 1738.132 | 6.828182 | 0.034757 |
Residual | 7 | 1781.868 | 254.5526 | ||
Total | 8 | 3520 |
Since p-value (0.034) is less than 0.05 we reject null hypothesis and conclude that there exist a significant linear relationship.
There is sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
c)
Player | Height (inches) xi | Weight (pounds) yi | xi^2 | yi^2 | xi*yi |
Player 1 | 75 | 225 | 5625 | 50625 | 16875 |
Player 2 | 75 | 197 | 5625 | 38809 | 14775 |
Player 3 | 72 | 180 | 5184 | 32400 | 12960 |
Player 5 | 69 | 185 | 4761 | 34225 | 12765 |
Player 6 | 74 | 190 | 5476 | 36100 | 14060 |
Player 7 | 75 | 228 | 5625 | 51984 | 17100 |
Player 8 | 71 | 200 | 5041 | 40000 | 14200 |
Player 9 | 75 | 230 | 5625 | 52900 | 17250 |
Sum | 586 | 1635 | 42962 | 337043 | 119985 |
Average | 73.25 | 204.375 |
Sxx = 37.5
Syy = 2889.875
Sxy = 221.25
b1 = Sxy/ Sxx = 5.9
b0 = 204.375 - 5.9*73.25 = -227.8
Y = 5.9X - 227.8
Test for significance
ANOVA | |||||
df | SS | MS | F | Significance F | |
Regression | 1 | 1305.375 | 1305.375 | 4.943042 | 0.067889 |
Residual | 6 | 1584.5 | 264.0833 | ||
Total | 7 | 2889.875 |
Since p-value (0.0678) is more than 0.05 we fail to reject null hypothesis and conclude that there doesnot exist a significant linear relationship between the height and weight of baseball players.
Yes Player 4 is an influential player.