SAS Institute SAS Institute Certifications A00-240 Questions & Answers

• Question 51:

  Refer to the REG procedure output:

  

  An analyst has selected this model as a champion because it shows better model fit than a competing model with more predictors. Which statistic justifies this rationale?

  A. R-Square

  B. Coeff Var

  C. Adj R-Sq

  D. Error DF

  Correct Answer: C

• Question 52:

  The selection criterion used in the forward selection method in the REG procedure is:

  A. Adjusted R-Square

  B. SLE

  C. Mallows' Cp

  D. AIC

  Correct Answer: B

• Question 53:

  The standard form of a linear regression model is:

  

  Which statement best summarizes the assumptions placed on the errors?

  A. The errors are correlated, normally distributed with constant mean and zero variance.

  B. The errors are correlated, normally distributed with zero mean and constant variance.

  C. The errors are independent, normally distributed with constant mean and zero variance.

  D. The errors are independent, normally distributed with zero mean and constant variance.

  Correct Answer: D

• Question 54:

  Refer to the REG procedure output:

  

  Click on the calculator button to display a calculator if needed.

  A. 0.4115

  B. 0.6994

  C. 0.5884

  D. 0.1372

  Correct Answer: A

• Question 55:

  Identify the correct SAS program for fitting a multiple linear regression model with dependent variable (y) and four predictor variables (x1-x4).

  

  A. Option A

  B. Option B

  C. Option C

  D. Option D

  Correct Answer: B

• Question 56:

  A non-contributing predictor variable (Pr > |t| =0.658) is added to an existing multiple linear regression model.

  What will be the result?

  A. An increase in R-Square

  B. A decrease in R-Square

  C. A decrease in Mean Square Error

  D. No change in R-Square

  Correct Answer: A

• Question 57:

  Spearman statistics in the CORR procedure are useful for screening for irrelevant variables by investigating the association between which function of the input variables?

  A. Concordant and discordant pairs of ranked observations

  B. Logit link (log (p/1-p))

  C. Rank-ordered values of the variables

  D. Weighted sum of chi-square statistics for 2x2 tables

  Correct Answer: C

• Question 58:

  A predictive model uses a data set that has several variables with missing values.

  What two problems can arise with this model? (Choose two.)

  A. The model will likely be overfit.

  B. There will be a high rate of collinearity among input variables.

  C. Complete case analysis means that fewer observations will be used in the model building process.

  D. New cases with missing values on input variables cannot be scored without extra data processing.

  Correct Answer: CD

• Question 59:

  This question will ask you to provide a missing option. Given the following SAS program:

  

  What option must be added to the program to obtain a data set containing Pearson statistics?

  A. OUTPUT=estimates

  B. OUTP=estimates

  C. OUTSTAT=estimates

  D. OUTCORR=estimates

  Correct Answer: B

• Question 60:

  An analyst investigates Region (A, B, or C) as an input variable in a logistic regression model.

  The analyst discovers that the probability of purchasing a certain item when Region = A is 1.

  What problem does this illustrate?

  A. Collinearity

  B. Influential observations

  C. Quasi-complete separation

  D. Problems that arise due to missing values

  Correct Answer: C