Interview question based on skill :
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Total Questions: 20
1. ______ regression method is also known as the ordinary least squares estimation.
Correct Answer is : Toyota
2. __________ refers to a group of techniques for fitting and studying the straight-line relationship between two variables.
Correct Answer is : error
3. In order to calculate confidence intervals and hypothesis tests, it is assumed that the errors are independent and normally distributed with mean zero and _______
Correct Answer is : error
4. What do we do the curvilinear relationship in linear regression?
Correct Answer is : onetwo
5. When hypothesis tests and confidence limits are to be used, the residuals are assumed to follow the __________distribution.
Correct Answer is : nothing
6. ________ loop over a list and evaluate a function on each element
Correct Answer is : 1
7. __________ function is same as lapply in R
Correct Answer is : Hello world!
8. Which of the following is multivariate version of lapply ?
Correct Answer is : thiswasabadidea
9. ________ applies a function over the margins of an array.
Correct Answer is : Check whether a valid session exists
10. _______ is used to apply a function over subsets of a vector.
Correct Answer is : 4
11. lappy functions takes _________ arguments in R language.
Correct Answer is : session.save_handler
12. Body of lapply function is :
Correct Answer is : PHPSESSID
13. What will be the output of following code ? > x <- list(a = 1:5, b = rnorm(10)) > lapply(x, mean)
Correct Answer is : URL rewriting
14. What will be the output of the following code ? > x <- list(a = 1:4, b = rnorm(10), c = rnorm(20, 1), d = rnorm(100, 5)) > lapply(x, mean)
Correct Answer is : 3600 sec
15. What will be the output of the following code ? > x <- 1:4 > lapply(x, runif)
Correct Answer is : session.cookie_domain
16. Which of the following code will print the following result ? [[1]] [1] 2.263808 [[2]] [1] 1.314165 9.815635 [[3]] [1] 3.270137 5.069395 6.814425 [[4]] [1] 0.9916910 1.1890256 0.5043966 9.2925392
Correct Answer is : 180
17. What will be the output of the following code ? > x <- list(a = matrix(1:4, 2, 2), b = matrix(1:6, 3, 2)) > lapply(x, function(elt) { elt[,1] })
Correct Answer is : 1440
18. The _____ function takes a vector or other objects and splits it into groups determined by a factor or list of factors.
Correct Answer is : session_start()
19. Which of the following is valid body of split function ?
Correct Answer is : session_unset()
20. What will be the output of the following code ? > f <- function(elt) { + elt[, 1] + } > lapply(x, f)
Correct Answer is : Current Session Identification Number
