The mean height of American women is about 63.4 inches and the standard deviatio
ID: 3310069 • Letter: T
Question
The mean height of American women is about 63.4 inches and the standard deviation is about 1.8 inches. The mean height of American men is about 66.6 inches with a standard deviation of 3.3 inches. The correlation between the heights of husbands and wives is about 0.4.
(A) We want to predict the height of the husband whose wife is 63.4 inches tall. The slope of the appropriate regression line is
(a) 20.1088
(b) 0.2182
(c) 0.7333
(d) 48.8679
(B) The intercept of the appropriate regression line is
a. 0.2182
b. 48.8679
c. 20.1088
d. 0.7333
(C) The predicted value of husbands height when wife’s height is 63.4 inches is
a. 64.1333
b. 66.60002
c. 1275.63122
(D) There are two data points, x1= wife’s height=63 with husband’s height= 70.7067, and another pair with x2=67.4 and y2=78.33322. If you use the regression line computed earlier then
i. The residual at x2 is equal to the residual at x1
ii. The residual at x2 is smaller than the residual at x1
iii. The residual at x2 is larger than the residual at x1
(E) The regression line that you found out in this problem is
i. The regression line of mens’s heights on women’s heights
ii. The regression line of womens’s heights on men’s heights
iii. It does not matter both are the same
please answer A-E if possible!
Explanation / Answer
A) slope b1=r*Sy/Sx =0.4*3.3/1.8=0.7333
option C
B)
intercept bo=Ybar-b1*Xbar =66.6-0.7333*63.4=20.1088
option C
C)
predicted value =20.1088+63.4*0.7333=66.60002
option B
d)
for residual for x1=Yactual -Yprediceted =70.7067-(20.1088+63*0.7333)=4.4
residual for X2 =Yactual -Yprediceted =78.3322-(20.1088+67.4*0.7333)=8.80
iii. The residual at x2 is larger than the residual at x1
E) i. The regression line of mens’s heights on women’s heights
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