/    /  R programming – Interview questions Part 10

1. What is the full form of SEM?

Answer: SEM stands for Structural Equation Modeling.

 

2. Which function performs classical multidimensional scaling?

Answer: classical multidimensional scaling function is used to perform cmdscale()

 

3. Define isoMDS().

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

 

4. Which function perform individual difference scaling?

Answer: It is done by indscal() function to perform individual difference scaling.

 

5. What is pvclust() function ?

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

 

6. Define cluster.stats() ?

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

 

7. What we use party package?

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

 

8. Which package provide the bootstrapping?

Answer: Boot package is used which provide bootstrapping.

 

9. Define MATLAB package.

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

 

10. What is the use of Matrix package?

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