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Correct option is (b) Require

Easiest explanation: Require () function is USUALLY used inside the other function and GIVES a warning WHENEVER a particular PACKAGE is not found. Library () function will give an ERROR message if the desired package is not loaded.

The CORRECT answer is (a) Vectorizing the function can be accomplished easily with the Vectorize() function

The EXPLANATION: Vectorize() function does not preserve the INVISIBILITY of the RETURN VALUE.

Correct choice is (a) Subset()

Explanation: Subset () function is used to select variables and observations from a given dataset. R has a large NUMBER of in-built functions and also the USER can CREATE their own functions.

The correct answer is (a) scoping rules

For explanation I would SAY: This function never actually uses the argument b, so CALLING f(2) will not PRODUCE an ERROR because the 2 gets positionally MATCHED to a.

The correct option is (a) loglm()

Explanation: loglm is fit log-linear models by iterative PROPORTIONAL scaling. This function PROVIDES a front-end of the STANDARD function, loglin, to allow log-linear models to be SPECIFIED and fitted in a MANNER similar to that of other fitting functions.

The correct choice is (a) 2

The best I can explain: R language consists of Homogeneous and HETEROGENEOUS data STRUCTURES. Homogeneous data structures have the same type of OBJECTS – Vector, Matrix and Array. Heterogeneous data structures have a different type of objects – Data FRAMES and lists.

The correct option is (c) NA & NAN

For explanation I would say: NaN (Not a NUMBER) is used to represent impossible VALUES whereas NA (Not Available) is referred to represent missing values. It is good to FIND the missing values and then TAKE the necessary STEPS to handle them.

Right choice is (B) traceback()

The best explanation: traceback() does nothing if there’s no ERROR. trace() INTERACTIVE tracing and debugging of calls to a FUNCTION or method.

Correct option is (B) Read.csv ()

The best EXPLANATION: read.csv () function is used for reading the .csv file in R language. We will use the built in the read.csv() function call, which reads the DATA as the data frame, and assign the data frame to a variable.

Correct choice is (b) HDFS

The explanation is: MAPREDUCE JOBS submitted from either OOZIE, Pig or Hive can be used for encode, improve and SAMPLE the data sets from HDFS into R. This helps to leverage complex analysis tasks with the subset of data prepared in R.

Right answer is (b) Dplyr

To explain: dplyr is a powerful R-package to transform and SUMMARIZE tabular data with rows and columns. dplyr package is used to speed up data FRAME management code. dplyr is a package for data MANIPULATION, written and MAINTAINED REGULARLY by Hadley Wickham.

The correct CHOICE is (c) t.tests ()

To explain I WOULD say: t.tests () function in R language is used to find out whether the means of 2 groups are equal to each other. It is not used most COMMONLY in R. It is used in some specific conditions.

The CORRECT OPTION is (d) Z <- (3, 4, 4)

For explanation: In R language when the vectors have different lengths, the multiplication begins with the smaller vector and continues till all the elements in the LARGER vector have been MULTIPLIED.

Right answer is (B) Error in log(c(-1, 2)): NaNs produced

To EXPLAIN I would say: Warning is produced due to negative VALUES.

Correct OPTION is (a) Dynamic scoping turns out to be particularly USEFUL for simplifying STATISTICAL computations

The explanation is: FREE variables are not formal arguments and are not local variables (ASSIGNED inside the function body).

Correct choice is (a) MATCH()

The explanation: It can be done using the match () function- match () function returns the first APPEARANCE of a particular element. The other way is to use %in% which returns a BOOLEAN VALUE either true or FALSE.

The CORRECT answer is (b) Substr

The best I can EXPLAIN: The substr() function gives a part of a string. The substr() METHOD will give parts of a string, beginning at the character of the specified position, and returns the specified number of characters.

The CORRECT choice is (a) Number

Best explanation: The CLASS of the resulting vector if you concatenate a number and NA is a Number. Decimal values are ALSO CALLED NUMERIC in R. It is the default computational data type in R language.

Right option is (d) All SORTS

Explanation: BUCKET Sort, Selection Sort, QUICK Sort, Bubble Sort, Merge Sort is the different sorts available in R LANGUAGE. Each and Every sorting algorithm is available in R.

The CORRECT choice is (d) empty

The best explanation: Every environment has a parent environment and it is possible for an environment to have MULTIPLE “CHILDREN”.

Right option is (B) Pairs

For explanation I WOULD say: Pairs FUNCTION takes various parameters LIKE FORMULA, data, subset, labels, etc. A matrix of scatterplots can be produced using pairs.

Correct answer is (a) POSIX represents a portable OPERATING system interface, primarily for UNIX systems

To explain I would say: Dates stored in the POSIX format are date/TIME values (LIKE dates with the chron library), but also allow modification of time zones.

Right choice is (a) Seq(9)

To explain: Seq generates a sequence of a PRIORI known pattern. Seq_along(6) will produce a vector with length 6 whereas seq(6) will produce a sequential vector from 1 to 6 C((1,2,3,4,5,6)).

Right option is (d) 3GB

To explain I would SAY: 8TB is the memory limit for 64-bit system memory and 3GB is the limit for 32-bit system memory. A solid UNDERSTANDING of R’s memory management will help you predict how much memory you’ll need for a given TASK.

Correct option is (B) Matrix DATA object

The EXPLANATION is: The function call is.matrix(X) returns TRUE then X can be termed as a matrix data object. R has a large NUMBER of in-built functions and also the user can create their own functions.

Correct option is (b) Import data

Best explanation: R COMMANDER is used to import data in R LANGUAGE. To start the R commander GUI, the user should type in the command Rcmdr into the console. There are 3 DIFFERENT types in which data can be imported in R language.

Correct choice is (c) Boxplot() or Text()

The explanation is: In the base GRAPHICS system, boxplot or text FUNCTION is USED to add ELEMENTS to a plot.

Correct CHOICE is (a) The traceback() FUNCTION must be called immediately after an error occurs

Easiest EXPLANATION: Once ANOTHER function is called, you LOSE the traceback.

Correct answer is (B) Cumsum

For explanation: The CUMULATIVE frequency DISTRIBUTION of a categorical VARIABLE can be checked using the cumsum () FUNCTION in the R language. The frequency distribution of a categorical variable can be checked using the table function in the R language.

Right answer is (a) warning()

The explanation is: warning is an INDICATION that SOMETHING is WRONG but not NECESSARILY fatal; execution of the function continues.

Right answer is (c) Setwd(“dir_path”)

To explain: The CURRENT R working ENVIRONMENT of a user which has user-defined objects like lists, vectors, ETC. is referred to as WORKSPACE in R language. The workspace of R is flexible to all functions of statistics.

Correct answer is (b) Hist

For explanation: Hist function is used to create a HISTOGRAM for visualisation in R programming LANGUAGE. The GENERIC function hist computes a histogram of the given data values. This function takes a VECTOR as the input and also uses some more parameters to PLOT histograms.

The correct option is (a) K-Nearest Neighbour

The BEST EXPLANATION: K-Nearest Neighbour is one type of the simplest machine LEARNING classification algorithms that is a subset of supervised learning based on lazy learning. In this ALGORITHM the function is approximated and also COMPUTATIONS are deferred until classification.

Correct CHOICE is (b) PAIRS

For explanation I would SAY: A MATRIX of scatterplots can be produced using pairs. Pairs function takes various parameters LIKE formula, data, subset, labels, etc.

Right answer is (b) Sapply

The explanation is: sapply() FUNCTION does the same JOBS as lapply() function but RETURNS a VECTOR. We can use a user built-in function into lapply() or sapply(). We create a function named avg to compute the average of the minimum and maximum of the vector.

The correct OPTION is (c) VAPPLY

Easy explanation: Vapply allows the programmer to specific the output type. The disadvantage of USING vapply is that it is verydifficult to be implemented and more verbose. vapply is SIMILAR to sapply, but has a pre-specified type of return VALUE, so it can be safer to use.

The correct choice is (b) Adegenet

Explanation: Adegenet package in R supports the EXPLORATORY analysis of genomic data. R has a large number of in-built functions and the user can CREATE their own functions. In R, a FUNCTION is an object so the R INTERPRETER is able to pass control to the function.

Right option is (a) Single document

The best I can explain: The best POSSIBLE way to do this is to COMBINE the data, code and analysis results for a single document by knitr for reproducible RESEARCH. This HELPS others to verify the findings, then engage in discussions.

Correct answer is (a) Coin

To explain I would say: Coin package in R language provides VARIOUS options for re-randomization and permutations based on statistical TESTS. When test assumptions cannot be MET then this package serves as a GOOD ALTERNATIVE to classical methods.

Right choice is (a) LOGICAL Regression

For explanation: Logistic regression can be USED for this and the function glm () in R language provides this functionality. Logistic regression is a STATISTICAL METHOD for analysing a dataset in which there are one or more independent variables which determine an outcome.

The correct ANSWER is (a) rbind()

The explanation: rbind () function can be used add datasets in R language PROVIDED the columns in the datasets should be the same. R has a LARGE number of in-built FUNCTIONS and also the user can create their own functions.