Exam 14: Building Multiple Regression Models

Inspection of the following table of correlation coefficients for variables in a multiple regression analysis reveals potential multicollinearity with variables ___________.

A local parent group was concerned with the increasing school cost for families with school aged children.The parent group was interested in understanding the relationship between the The academic grade level for the child and the total costs spent per child per academic year.They Performed a multiple regression analysis using total cost as the dependent variable and academic Year (x₁)as the independent variables.The multiple regression analysis produced the following Tables. These results indicate that ____________.

If two or more independent variables are highly correlated,the regression analysis might suffer from the problem of singular collinearity.

If the effect of an independent variable (e.g.,square footage)on a dependent variable (e.g.,price)is affected by different ranges of values for a second independent variable (e.g.,age ),the two independent variables are said to interact.

A multiple regression analysis produced the following tables. Using $\alpha$ = 0.10 to test the null hypothesis H0: $\beta$ 2 = 0,the critical t value is ____.

If a data set contains k independent variables,the "all possible regression" search procedure will determine 2^k - 1 different models.

Stepwise regression is one of the ways to prevent the problem of multicollinearity.

Inspection of the following table of correlation coefficients for variables in a multiple regression analysis reveals potential multicollinearity with variables ___________.

An appropriate method to identify multicollinearity in a regression model is to ____.

Inspection of the following table of correlation coefficients for variables in a multiple regression analysis reveals that the first independent variable entered by the forward selection procedure will be ___________.

Alan Bissell,a market analyst for City Sound Online Mart,is analyzing sales from heavy metal song downloads.Alan's dependent variable is annual heavy metal song download sales (in $1,000,000's),and his independent variables are website visitors (in 1,000's)and type of download format requested (0 = MP3,1 = other).Regression analysis of the data yielded the following tables. For a 'other' download formats with 10,000 website visitors,Alan's model predicts annual sales of heavy metal song downloads of ________________.

If a square-transformation is applied to a series of positive numbers,all greater than 1,the numerical values of the numbers in the transformed series will be smaller than the corresponding numbers in the original series.

Yvonne Yang,VP of Finance at Discrete Components,Inc.(DCI),wants a regression model which predicts the average collection period on credit sales.Her data set includes two qualitative variables: sales discount rates (0%,2%,4%,and 6%),and total assets of credit customers (small,medium,and large).The number of dummy variables needed for "sales discount rate" in Yvonne's regression model is ________.

Regression models in which the highest power of any predictor variable is 1 and in which there are no cross product terms are referred to as first-order models.

Yvonne Yang,VP of Finance at Discrete Components,Inc.(DCI),wants a regression model which predicts the average collection period on credit sales.Her data set includes two qualitative variables: sales discount rates (0%,2%,4%,and 6%),and total assets of credit customers (small,medium,and large).The number of dummy variables needed for "total assets of credit customer" in Yvonne's regression model is ________.

A qualitative variable which represents categories such as geographical territories or job classifications may be included in a regression model by using indicator or dummy variables.

If the variance inflation factor is bigger than 10,the regression analysis might suffer from the problem of multicollinearity.

Which of the following iterative search procedures for model-building in a multiple regression analysis starts with all independent variables in the model and then drops non-significant independent variables is a step-by-step manner?

We may use logistic regression when the dependent variable is a dummy variable,coded 0 or 1.

An "all possible regressions" search of a data set containing "k" independent variables will produce __________ regressions.