Episode 74 : R Programming Questions and Answers – Version 9

86. What is the use of MASS package?

MASS functions include those functions which performs linear and quadratic discriminant function analysis.

87. Define qda().

qda() prints a quadratic discriminant function.

88. Define lda().

lda() is used to print the discriminant functions which is based on centered variable.

89. What is the use of forecast package?

It provides the functions which are used for automatic selection of ARIMA and exponential models.

90. Define auto.arima().

It is used to handle the seasonal as well as non-seasonal ARIMA models.

91. What is principal() function?

It is define in psych package which is used to rotate and extract the principal components.

92. What is FactoMineR?

It is a package which includes quantitative and qualitative variables. It also includes supplementary variables and observations.

93. What is the full form of CFA?

CFA stands for Confirmatory Factor Analysis.

94. What is the use of boot.sem() function?

It is used to bootstrap the structural equation model.

95. What is the full form of SEM?

SEM stands for Structural Equation Modeling.

96. Which function performs classical multidimensional scaling?

cmdscale() function is used to perform classical multidimensional scaling.

97. Define isoMDS().

This function is defined under the MASS package which performs nonmetric multidimensional scaling.

98. Which function perform individual difference scaling?

It is done by indscal() function.

99. What is pvclust() function ?

It comes under the pvclust package which provides p-values for hierarchical clustering.

100. Define cluster.stats() ?

It is define in fpc package which provide a method for comparing the similarity of two clusters solution using different validation criteria.

101. What we use party package?

It is used to provide a non-parametric regression for ordinal, nominal, censored and multivariate responses.

102. Which package provide the bootstrapping?

boot package is used which provide bootstrapping.

103. Define MATLAB package.

Matlab package includes those wrapper functions and variable which are used to replicate matlab function calls.

104. What is the of use Matrix package?

Matrix package includes those function which support sparse and dense matrices like Lapack, BLAS etc.