(Solved): WPC 300 Quiz 5 Score for this attempt: 20 out of 20 Submitted Apr 15 at 10:10am...

WPC 300 Quiz 5
Score for this attempt: 20 out of 20
Submitted Apr 15 at 10:10am
This attempt took 11 minutes.

Question 1
2 / 2 pts
A market analyst is developing a regression model to predict monthly household expenditures on groceries as a function of family size, household income, and household neighborhood (urban, suburban, and rural). The "neighborhood" variable in this model is ________.

• A continuous variable
• A dependent variable
• A qualitative variable
• An independent variable

  
Question 2
2 / 2 pts
The unexplained variance in the regression analysis is also known as:

• Predicted variance
• Residual variance
• Regression variance
• Total variance

  
Question 3
2 / 2 pts
Which of the following statement is true based on the following regression equation?
IQ = 4.0 + Reading Label * 5.6

• A unit point change in IQ will result in 5.6 point increase in reading label
• A unit point change in reading label will increase IQ by 5.6 point
• A unit point change in IQ will result in 9.6 point increase in reading label
• Reading label is not a good predictor of IQ

  
Question 4
2 / 2 pts
The value of R-Squared always falls between ___________ and ___________ inclusive.

• -infinity to + infinity
• -1 and +1
• 0 and -1
• 0 and 1

  
Question 5
2 / 2 pts
A correlation coefficient between "college entrance exam" grades and scholastic achievement was found to be -1.08. On the basis of this, you would tell the university that:

• They should hire a new statistician.
• The exam is a poor predictor of success.
• Students who do best on this exam will make the worst students.
• The entrance exam is a good predictor of success.

 Feedback: -1< r<1
 
Question 6
2 / 2 pts
You need to find out which customer is likely to buy your product. A sample data is available from your current customer base. Which of the following analysis method will be appropriate for this study?

• Linear regression
• Multiple linear regression
• Logistic regression
• Clustering

  
Question 7
2 / 2 pts
Which of the following is true about multi-collinearity?

• The effect of a dependent variable on another becomes difficult to isolate.
• P-value reduces significantly leading to rejection of the null hypothesis.
• Regression coefficients become clearer and are easier to interpret
• Is measured using the statistical variance inflation factor (VIF)

 
 
Question 8
2 / 2 pts
The correlation coefficient between the age of an auto and the money spent to repair is 0.9. Which of the following statement is true?

• 81% of the variation in the money spent on repairs is explained by the age of the auto
• 81% of money spent on repairs is explained by the age of an auto
• 90% of the money spent on repair is explained by the age of an auto
• 90% of the repair cost will be explained by the age of an auto

Feedback: R=0.9, R-squared = 0.81. Remember the definition of R-squared.
 
Question 9
2 / 2 pts
A manager wishes to predict the annual cost (y) of an automobile based on the number of miles (x) driven. The following model was developed: y = $1500 + 0.36x. If a car is driven 15000 miles, the predicted cost of the car is:

• $6900
• $2090
• $3850
• $7400

  
Question 10
2 / 2 pts
Which of the following assumptions is not true for multiple linear regression?

• Residuals are normally distributed
• Presence of multi-collinearity effect
• Relationship between dependent and independent variables should be linear
• No correlations between the independent variables