R Programming Language Certification Statistical Analysis & Modeling 2

Question 1

Which family argument in glm() is used for logistic regression?

Accepted Answer

binomial

Answer

gaussian

Answer

poisson

Answer

gamma

Question 2

What does the confint() function compute for a fitted model in R?

Accepted Answer

Confidence intervals for model coefficients

Answer

Prediction intervals for new data

Answer

AIC and BIC values

Answer

Variance inflation factors

Question 3

Which test should you use to compare variances between two groups in R?

Accepted Answer

var.test()

Answer

t.test()

Answer

bartlett.test()

Answer

levene.test()

Question 4

What does AIC stand for in model selection?

Accepted Answer

Akaike Information Criterion

Answer

Average Information Criterion

Answer

Adjusted Index of Correlation

Answer

Analytic Information Coefficient

Question 5

Which R function performs a Wilcoxon rank-sum test (non-parametric equivalent of t-test)?

Accepted Answer

wilcox.test()

Answer

mann.whitney()

Answer

ranksum()

Answer

nonpar.test()

Question 6

What does the predict() function do when called on a fitted lm() model?

Accepted Answer

Generates predicted values for new or existing data

Answer

Retrains the model on new data

Answer

Plots model residuals

Answer

Computes cross-validation scores