Practice Tricky R Programming Multiple Choice Questions with Answers Quiz-1 - MCQGeeks.com

Q.1.

Which of the following code will drop the nth column?

a) new <- old[-n,]
b) new <- old[,-n]
c) new <- old[,-c(i,j)]
d) new <- subset(old,logical)

Explanation

Q.2.

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

a) new <- old[-n,]
b) new <- old[,-n]
c) new <- old[,-c(i,j)]
d) new <- subset(old,logical)

Explanation

Q.3.

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

a) complete <- subset(data.df,complete.cases(data.df)
b) complete <- sub(data.df,complete.cases(data.df)
c) complete <- subset(data.df,completeall.cases(data.df)
d) new <- old[n1:n2,n3:n4]

Explanation

Q.4.

Which of the following statement is normal distribution?

a) dnorm(x, mean=0, sd=1, log = FALSE)
b) pnorm(q, mean=0, sd=1, lower.tail = TRUE, log.p = FALSE)
c) qnorm(p, mean=0, sd=1, lower.tail = TRUE, log.p = FALSE)
d) rnorm(n, mean=0, sd=1)

Explanation

Q.5.

which of the following statement gives cumulative sum?

a) cumsum(x,na=rm=TRUE)
b) cumprod(x)
c) cummax(x)
d) cummin(x)

Explanation

Q.6.

Which of the following is uniform distribution?

a) dunif(x, min=0, max=1, log = FALSE)
b) punif(q, min=0, max=1, lower.tail = TRUE, log.p = FALSE)
c) qunif(p, min=0, max=1, lower.tail = TRUE, log.p = FALSE)
d) runif(n, min=0, max=1)

Explanation

Q.7.

Which of the following truncates real x to integers?

a) as.order(x)
b) as.integer(x)
c) as.numeric(x)
d) as.character(x)

Explanation

Q.8.

Which of the following tests each element of x for membership in y?

a) y%in%x
b) all(x)
c) any(x)
d) x%in%y

Explanation

Q.9.

Which of the following finds the maximum value in the vector x, exclude missing values?

a) rm(x)
b) max(x, na.rm=TRUE)
c) all(x)
d) x%in%y

Explanation

Q.10.

Which of the following produces the variance covariance matrix?

a) sd(x, na.rm=TRUE)
b) mad(x, na.rm=TRUE)
c) fivenum(x, na.rm=TRUE)
d) var(x, na.rm=TRUE)

Explanation