Basics of R Programming: Data Types and Matrices

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What is the primary use of R programming language?

Web Development
Artificial Intelligence
Data Science (correct)
Database Management

What is the significance of the matrix() function in R?

It creates a list of characters
It creates a three-dimensional array
It creates a two-dimensional array (correct)
It creates a one-dimensional array

How can you access the element in the 2nd row and 3rd column of a matrix P?

P[,3]
P[2,3] (correct)
P[3,2]
P[2,]

What is the department of the employee with emp_id 4?

HR (B) Signup and view all the answers

What is the purpose of the byrow argument in the matrix() function?

To arrange elements sequentially by row (D) Signup and view all the answers

What is the type of the start_date column in the employee_data dataframe?

Date (A) Signup and view all the answers

What is the difference between a matrix and an array in R?

A matrix is a two-dimensional array, while an array can be more than two-dimensional (A) Signup and view all the answers

What is the purpose of the Pearson correlation test?

To evaluate the association between two variables (C) Signup and view all the answers

What is the output of the command print(P[2,])?

All elements in the 2nd row (D) Signup and view all the answers

How many rows are in the employee_data dataframe after expansion?

8 (C) Signup and view all the answers

What is the name of the employee with emp_id 3?

Michelle (B) Signup and view all the answers

What is the dimension of the array created in the example?

4x2x3 (D) Signup and view all the answers

What is the output of `print(result[3,2,2])`?

12 (B) Signup and view all the answers

How are the columns and rows named in the matrix?

Using the column.names and row.names functions (C) Signup and view all the answers

What is the data type of the object 'factor.data'?

Factor (B) Signup and view all the answers

What is the purpose of a factor in R?

To store categorical data (A) Signup and view all the answers

What is the structure of a data frame in R?

A table with variables and observations (B) Signup and view all the answers

What type of relationship does the Pearson correlation coefficient measure?

Linear dependence (B) Signup and view all the answers

What is the assumption of the Spearman rho test?

Variables should be measured on an ordinal or continuous level (C) Signup and view all the answers

What is the purpose of the Shapiro test?

To check for normality of distribution (C) Signup and view all the answers

When would you use Kendall tau test?

When there are tied ranks (A) Signup and view all the answers

What is the graphical method to check for normality of distribution?

Q-Q plot (C) Signup and view all the answers

What is the condition to use Pearson correlation coefficient?

Variables should be measured on an ordinal or continuous level and should be normally distributed (C) Signup and view all the answers