| Snaprecruit.com

| Snaprecruit.com

Interview question based on skill :

Take as many assements as you can to improve your validate your skill rating

Total Questions: 20

1. Which programming language is more based on the results?

Correct Answer is : R

2. Why learning R becomes tough?

Correct Answer is : Special Cases

3. R is mostly used in ______________

Correct Answer is : All of the mentioned

4. Why is it needed for R studio to update regularly?

Correct Answer is : Bugs

5. What is the meaning of “<-“?

Correct Answer is : Assignment

6. In the expression x <- 4 in R, what is the class of ‘x’ as determined by the `class()’ function?

Correct Answer is : Integer

7. Which of the following code create n samples of size “size” with probability prob from the binomial ?

Correct Answer is : z <- rbinom(n,size,prob)

8. Which of the following code create a n item vector of random normal deviates ?

Correct Answer is : x1 <- c(rnorm(n))

9. Which of the following statement can read csv files ?

Correct Answer is : read.table(filename,header=TRUE,sep=’,’)

10. Which of the following statement read a tab or space delimited file ?

Correct Answer is : read.table(filename,header=TRUE)

11. which of the following statement chose those objects meeting a logical criterion ?

Correct Answer is : subset(dataset,logical)

12. Which of the following statement is another way to get a subset ?

Correct Answer is : data.df[data.df=logical].

13. Which of the following sort a dataframe by the order of the elements in B

Correct Answer is : x[rev(order(x$B)),].

14. Which of the following is Mac menu command ?

Correct Answer is : browse.workspace

15. _____ list the variables in the workspace

Correct Answer is : ls()

16. ___________ remove all the variables from the workspace

Correct Answer is : rm(list=ls())

17. Which of the following code will drop the nth column ?

Correct Answer is : new <- old[-n,].

18. Which of the following code drop the ith and jth column ?

Correct Answer is : new <- old[,-c(i,j)].

19. Which of the following statement find cases with no missing values ?

Correct Answer is : complete <- subset(data.df,complete.cases(data.df)

20. Which of the following statement is normal distribution ?

Correct Answer is : dnorm(x, mean=0, sd=1, log = FALSE)