- Interview Prep
- Tutorials
- Tracks
R Programming Quiz
Question 1
How can you perform linear regression in R using the lm() function?
mice.impute()
impute.data()
mice()
mice::complete()
Question 2
In R, what is the purpose of the summary() function when applied to a linear regression model created with lm()?
Displays a summary of the model's coefficients
Displays a summary of the model's residuals
Provides a summary of the model's performance metrics
Presents an overview of the model's input features
Question 3
In R, what is the purpose of the `purrr` package's `map()` function?**
Applies a function to each element of a vector and returns a list
Applies a function to each row of a data frame and returns a vector
Applies a function to each element of a list and returns a list of results
Applies a function to each column of a matrix and returns a matrix
Question 4
What is the purpose of the `reshape2` package's `melt()` function in R?**
Melts a data frame from wide to long format
Casts a data frame from long to wide format
Reshapes a data frame by merging columns
Applies a function to each element of a matrix
Question 5
What does the following R code do?
df <- data.frame(name = c("Alice", "Bob", "Charlie"),
age = c(25, 30, 22))
Creates a matrix with two columns: "name" and "age"
Creates a data frame with two columns: "name" and "age"
Creates a list with two elements: "name" and "age"
Raises an error due to incorrect syntax
Question 6
What does the following R code do?
x <- c(1, 2, 3, 4, 5)
y <- sum(x)
Creates a vector x with values 1 to 5
Calculates the mean of vector x
Calculates the sum of vector x
Raises each element of vector x to the power of 2
Question 7
What is the purpose of the strsplit() function in R?
Splits a string into substrings based on a specified delimiter
Concatenates strings into a single string
Reverses the order of characters in a string
Extracts a substring from a string
Question 8
In R, what does the dendrogram class represent in hierarchical clustering?
A scatter plot of data points
A matrix of distances between data points
A tree-like structure representing the clustering hierarchy
A network graph of relationships between variables
Question 9
In R, what does the mutate() function from the dplyr package do?
Adds new variables or modifies existing ones in a data frame
Performs matrix multiplication
Mutates the entire data frame
Deletes variables from a data frame
Question 10
In R, what does the lapply() function do?
Applies a function to each element of a list and returns a list of the results
Applies a function to each element of a vector and returns a vector
Applies a function to each column of a data frame and returns a list of the results
Applies a function to each row of a matrix and returns a list of the results
There are 25 questions to complete.