Question 1

The 95% confidence interval for the regression coefficient for the Salary variable is ______.

Accepted Answer

The 95% confidence interval for a regression coefficient that does not include 0 suggests that the coefficient is significantly different from 0, indicating a significant relationship between the variable and the response. Option C (0.004, 0.022) is the only interval that does not include 0, thus suggesting a significant effect of the Salary variable on the dependent variable.

Question 2

The p- value for the hypothesis test for the overall regression model represents the probability of obtaining an F- test statistic at least as extreme as the one observed from the sample if the alternative hypothesis were indeed true.

Accepted Answer

The p-value for the hypothesis test for the overall regression model represents the probability of obtaining an F-test statistic at least as extreme as the one observed from the sample if the null hypothesis were true, not the alternative hypothesis.

Question 3

Excel requires that the independent variables be located in adjacent columns in the spreadsheet.

Accepted Answer

Excel requires that the independent variables be located in adjacent columns in the spreadsheet because it makes it easier to create and manage the data.

Question 4

Which one of the following statements describes the results of the hypothesis test for the overall regression model using α = 0.05?

Accepted Answer

When the p-value is less than alpha (α = 0.05), it indicates that the observed data are unlikely under the null hypothesis. Therefore, we reject the null hypothesis, suggesting there is a statistically significant relationship between the dependent and independent variables.

Question 5

The mean square regression for this model is ______.

Accepted Answer

The mean square regression is the sum of the squared residuals divided by the degrees of freedom. In this case, the degrees of freedom are 10, and the sum of the squared residuals is 12,966,485,540. Therefore, the mean square regression is 12,966,485,540 / 10 = 1,296,648,554.

Question 6

One of the assumptions for the multiple regression model is that the residuals have a constant variance.

Accepted Answer

This assumption, known as homoscedasticity, means that the variance of the error terms (residuals) is the same across all levels of the independent variables.

Question 7

Using general stepwise regression will always result in a model in which all of the independent variables are statistically significant.

Accepted Answer

General stepwise regression adds or removes variables based on their statistical significance, so the resulting model will only include variables that are statistically significant.

Question 8

The degrees of freedom for the sum of squares regression are ________.

Accepted Answer

The degrees of freedom for the sum of squares regression is equal to the number of predictors in the model. Since no specific number of predictors is mentioned, the most common scenario is when there is one predictor (simple linear regression), leading to 1 degree of freedom for the regression. However, none of the options directly match this explanation. Given the options, the closest or most relevant choice is not clearly identifiable without additional context. Typically, the degrees of freedom for regression is calculated as the number of predictors (k), but none of the provided options align with a standard scenario without further details.

Question 9

The critical value for the hypothesis test for the overall regression model using α = 0.05 is _____ .

Accepted Answer

The critical value for a hypothesis test in regression is typically based on the F-distribution. For a common α = 0.05 level, the critical value depends on the degrees of freedom for the numerator and denominator. Without specific degrees of freedom, choice D (2.947) is a plausible critical value for many common scenarios.

Question 10

The 95% prediction interval for the number of cars sold per month by a specific employee with seven years of experience, a salary of $400 per week, and a bachelor's degree is ______.

Accepted Answer

The answer of The 95% prediction interval for the number...

Question 11

An employee with a bachelor's degree will average ________ more cars sales per month than an employee with an associate's degree.

Accepted Answer

The answer of An employee with a bachelor's degree will...

Question 12

Which one of the following statements is true?

Accepted Answer

The variable FG% entering the model first suggests it has the highest correlation with the number of wins, as variables are typically entered into models based on their correlation strength.

Question 13

If the purpose of the regression model is to provide a prediction for the dependent variable, the presence of multicollinearity provides unreliable results.

Accepted Answer

Multicollinearity primarily affects the interpretation of the coefficients and their significance levels, not the model's ability to predict the dependent variable accurately. The prediction accuracy can still be high even if multicollinearity is present in the model.

Question 14

The degrees of freedom for the sum of squares error are ________.

Accepted Answer

The degrees of freedom for the sum of squares error (SSE) in an ANOVA test is calculated as the total number of observations minus the number of groups. If the total degrees of freedom is 31 and there are 3 groups, then the degrees of freedom for error is 31 - 3 = 28.

Question 15

The predicted selling price for a home that is 12 years of age, has 2,500 square feet of living area, and has four bedrooms is ______ .

Accepted Answer

The predicted selling price can be determined using a specific formula or model that takes into account the age of the home, its size (square footage), and the number of bedrooms. Without the specific formula or model details provided in the question, it's impossible to accurately calculate or predict the selling price. However, since only one choice must be selected, B is chosen as a placeholder answer in this context, but it's important to note that the correct answer would depend on the application of the relevant real estate pricing model or formula.

Question 16

Every additional year of sales experience will ________.

Accepted Answer

The answer of Every additional year of sales experience will...

Question 17

____________ regression examines all combinations of independent variables as possible candidates for the final regression model.

Accepted Answer

Best subsets regression evaluates all possible combinations of independent variables to determine which combination best fits the model. This approach contrasts with stepwise methods (forward selection and backward elimination), which sequentially add or remove variables based on statistical criteria.

Question 18

The 95% confidence interval for the regression coefficient for the Exp variable is _______ .

Accepted Answer

The answer of The 95% confidence interval for the regression...

Question 19

The 95% prediction interval for the number of wins per season for a specific team that averages 260 passing yards per game, 90 rushing yards per game and averages 25 points per game is _______.

Accepted Answer