DMUR_BBA_24_25-Quiz

How do you assign a value to a variable in R?

• • x = 5

• • x <- 5

• • x := 5

• • x >- 5

Which function is used to create a sequence of numbers in R?

• • seq()

• • range()

• • create()

• • numbers()

What does the summary() function provide for a statistical analysis in R?

• • Descriptive statistics

• • Inferential statistics

• • Predictive modeling

• • Time series analysis

Which function is used to generate random numbers from a normal distribution in R?

• • random.normal()

• • rnorm()

• • randn()

• • normrnd()

What is the purpose of the apply() function in R?

• • Applying a mathematical function to a vector

• • Applying a function to each element of an array

• • Applying a conditional statement to a data frame

• • Applying a regression model

How can you rename a column in a data frame in R?

• • rename_column(df, old_name, new_name)

• • change_column_name(df, old_name, new_name)

• • colnames(df)[colnames(df) == "old_name"] <- "new_name"

• • update_column(df, old_name, new_name)

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

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

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

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