Homework Sourse1 1 point A linear regression analysis is inappropriate when
1. (1 point) A linear regression analysis is inappropriate when
a. the scatterplot of X and Y form a reasonably straight line.
b. you want to make predictions for one variable based on another.
c. Y and X are both interval or ratio variables.
d. Y and X are both categorical variables.
e. X and Y form a bivariate distribution.
2. (1 point) As the value of robs gets smaller, the prediction for Y
a. gets larger
b. gets smaller
c. gets closer to the mean of Y
d. gets closer to the mean of X
e. does not change
3. (1 point) As the value of robs gets smaller, the error in prediction from the linear regression line
a. gets larger
b. gets closer to the standard deviation of Y
c. gets closer to the standard deviation of X
d. both a and b
e. both a and c
4. (1 point) We want to predict the weekly cost of groceries from the number of individuals in a household. In trying to construct the regression equation, we know the mean number of people in a household is 3.25 and the mean weekly grocery bill is $130. If the slope of the regression is b=22 what is the Y intercept, a?
a. 3.25
b. -58.5
c. 22
d. 58.5
e. 400.5
5. (1 point) The regression equation for predicting the number of speeding tickets from the driver’s age is Y= -0.06X+5.5. How many tickets do you predict a 20 year old would get?
a. 5.5
b. 5.0
c. 4.3
d. 0.06
e. -0.06
Solution
1. (1 point) A linear regression analysis is inappropriate when
2. (1 point) As the value of robs gets smaller, the prediction for Y
3. (1 point) As the value of robs gets smaller, the error in prediction from the linear regression line
a. gets larger
4. (1 point) We want to predict the weekly cost of groceries from the number of individuals in a household. In trying to construct the regression equation, we know the mean number of people in a household is 3.25 and the mean weekly grocery bill is $130. If the slope of the regression is b=22 what is the Y intercept, a?
Solution : 130 - (22*3.25) = 58.5
d. 58.5
5. (1 point) The regression equation for predicting the number of speeding tickets from the driver’s age is Y= -0.06X+5.5. How many tickets do you predict a 20 year old would get?
c. 4.3
solution ( -0.06*20 + 5.5 = 4.3)
Hope this helps.
