Exam 14: Building Multiple Regression Models

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. Using $\alpha$ = 0.05 to test the null hypothesis H₀: $\beta$ ₂ = 0,the critical t value is ____.

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. The sample size for this analysis is ____________.

The logistic regression model constrains the estimated probabilities to lie between 0 and 100.

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

Abby Kratz,a market specialist at the market research firm of Saez,Sikes,and Spitz,is analyzing household budget data collected by her firm.Abby's dependent variable is weekly household expenditures on groceries (in $'s),and her independent variables are annual household income (in $1,000's)and household neighborhood (0 = suburban,1 = rural).Regression analysis of the data yielded the following table. However,Abby has reasons to believe that actually suburban households have a higher propensity to spend in groceries than rural households,as they tend to make more impulse purchasing decisions.In this new model,the actual income coefficient for the suburban families is 1.735272α,for some α > 1.If new data confirms that suburban houses with an annual income of $95,773.44 have the same weekly grocery spending than rural households,then α = ______.

If there are 6 independent variables,then there are ______ possible regressions with 2 predictors and ______ possible regressions with 3 predictors.

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 ___________.

A research project was conducted to study the effect of smoking and weight upon resting pulse rate.The response variable is coded as 1 when the pulse rate is low and 0 when it high.Smoking is also coding as 1 when smoking and 0 when not smoking.Shown below is Minitab output from a logistic regression. Response Information Variable Value Count Rating Pulse 1 70 (Event) 0 22 Total 92 Logistic Regression Table Odds 95% CI Predictor Coef SE Coef Z P Ratio Lower Upper Constant -1.98717 1.67930 -1.18 0.237 Weight 0.0250226 0.0122551 2.04 0.041 1.03 1.00 1.05 Smokes -1.19297 0.552980 -2.16 0.031 0.30 0.10 0.90 Log-Likelihood = -46.820 Test that all slopes are zero: G = 7.574,DF = 2,P-Value = 0.023 The log of the odds ratio or logit equation is:

An "all possible regressions" search of a data set containing 8 independent variables will produce ______ regressions.

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

A multiple regression analysis produced the following tables. The sample size for this analysis is ____________.

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?

An "all possible regressions" search of a data set containing 7 independent variables will produce ______ regressions.

A regression analysis conducted to predict an independent variable by other independent variables ______.

Abby Kratz,a market specialist at the market research firm of Saez,Sikes,and Spitz,is analyzing household budget data collected by her firm.Abby's dependent variable is weekly household expenditures on groceries (in $'s),and her independent variables are annual household income (in $1,000's)and household neighborhood (0 = suburban,1 = rural).Regression analysis of the data yielded the following table. The marginal propensity to consume (MPC)is defined in economics as the proportion of an additional dollar of income that a household (or individual)consumes.Assume that grocery spending is the main expenditure of households.Then according to the regression analysis above,the MPC ______.

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

A researcher wants to address multicollinearity using the guideline that a variance inflation factor (VIF)greater than 9 will indicate a severe multicollinearity problem.This means that the highest coefficient of determination allowed will be ______.

Abby Kratz,a market specialist at the market research firm of Saez,Sikes,and Spitz,is analyzing household budget data collected by her firm. Abby's dependent variable is weekly household expenditures on groceries (in $'s),and her independent variables are annual household income (in $1,000's)and household neighborhood (0 = suburban,1 = rural). Regression analysis of the data yielded the following table. Abby's model is ________________.

Which of the following iterative search procedures for model-building in a multiple regression analysis reevaluates the contribution of variables previously include in the model after entering a new independent variable?

If a qualitative variable has c categories,then only (c - 1)dummy variables must be included in the regression model.