# QNT 275 Week 4 Quiz

1 - For a given set of explanatory variables, in general:

a confidence interval is narrower than a prediction interval.

a confidence interval is wider than a prediction interval.

The width of a confidence interval cannot be determined.

the width of a confidence interval is the same as the width of a prediction interval.

2- The standard error of the estimate measures:

the variability of the observed y-values around the predicted y-values.

the variability of the predicted y-values around the mean of the observed y-values.

the variability of the values of the sample regression coefficients.

the variability of the explanatory variables.

3- In a simple linear regression model, if the plots on a scatter diagram lie on a straight line, what is the standard error of the estimate?

+1

-1

Infinity

0

4- Which of the following variables is not qualitative?

Gender of a person

Religious affiliation

Student's status (freshman, sophomore, etc.)

Number of dependents claimed on a tax return

5- Consider the following simple linear regression model: The response variable is:

β0

x

y

ε

6- Another name for an explanatory variable is the ___.

descriptive variable

independent variable

inferred variable

dependent variable

7- Serial correlation is typically observed in:

outliers.

sparse data.

cross-sectional data.

time series data.

8- Consider the following simple linear regression model: β_{0} and β_{1} are:

the unknown parameters.

the random error terms.

the response variables.

the explanatory variables.

9 - What is the name of the variable that's used to predict another variable?

Coefficient of Determination

Standard Error of the Estimate

Response

Explanatory

10- Which of the following violates the assumptions of regression analysis?

The error term has a constant variance.

The error term has a zero mean.

The error term is normally distributed.

The error term is correlated with an explanatory variable.