# (Solved): Wpc300 Quiz 5: Regression ...

**Wpc300**

**Quiz 5: Regression **

**The score for this quiz: 10 out of 10**

**Question 1**

**1 / 1 pts**

What would be the null hypothesis for testing a linear regression model with profit as the dependent variable and sales as the independent variable?

- There is a negative relationship between profit and sales.
- There is a linear relationship between profit and sales that can be either positive or negative.
- There is no linear relationship between profit and sales.
- There is a positive relationship between profit and sales.

**Question 2**

**1 / 1 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 linear variable
- an independent variable
- a continuous variable
- a dependent variable

**Question 3**

**1 / 1 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 9.6-point increase in reading label.
- Reading label is not a good predictor of IQ.
- 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.

**Question 4**

**1 / 1 pts**

The value of R-Squared always falls between ________ and ________, inclusive.

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

**Question 5**

**1 / 1 pts**

The correlation coefficient between the age of a vehicle and the money spent to repair it is 0.9. Which of the following statement is true?

- 90% of the repair cost will be explained by the age of the vehicle
- 90% of the money spent on repair is explained by the age of the vehicle
- 81% of the variation in the money spent on repairs is explained by the age of the vehicle
- 81% of money spent on repairs is explained by the age of the vehicle

**Question 6**

**1 / 1 pts**

Which of the following is true about multi-collinearity?

- The effect of an independent variable on the dependent variable becomes easy to isolate.
- The regression coefficients become clearer and are easier to interpret.
- It is measured using a measure called variance inflation factor (VIF).
- The P-value reduces significantly, leading to rejection of the null hypothesis.

**Question 7**

**1 / 1 pts**

The unexplained variance in the regression analysis is also known as:

- Total variance
- Residual variance
- Predicted variance
- Regression variance

**Question 8**

**1 / 1 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:

- The entrance exam is a good predictor of success.
- 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.

**Question 9**

**1 / 1 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 in a year, the model predicts the annual cost of the car to be:

- $7400
- $3850
- $2090
- $6900

**Question 10**

**1 / 1 pts**

Which of the following assumptions is not true for multiple linear regression?

- The independent variables are not correlated.
- The relationship between dependent and independent variables is linear.
- There will be a multi-collinearity effect.
- The residuals are normally distributed.