R Online Test

Q: What are the main data analysis tests?

Key tests in this category include: Data Analysis Test Data Science Assessment Test Data Wrangling Test

The R Online Test uses scenario-based MCQs to evaluate candidates on their knowledge of R programming language, including their proficiency in working with data structures, control structures, functions, and data visualization using R libraries like ggplot2. The test includes a coding question to evaluate hands-on R programming skills and aims to evaluate a candidate's ability to work with R effectively for data analysis and statistical modeling.

Covered skills:

Vectors
Matrices
Dataframes
CSV Handling
Linear regression
Confusion matrix
Random Forest
Analytics with R
String Manipulation

Get started for free

Preview questions

About the R Test

The R Online Test helps recruiters and hiring managers identify qualified candidates from a pool of resumes, and helps in taking objective hiring decisions. It reduces the administrative overhead of interviewing too many candidates and saves time by filtering out unqualified candidates at the first step of the hiring process.

The test screens for the following skills that hiring managers look for in candidates:

Efficiently working with vectors
Working with matrices for data manipulation
Handling and analyzing data using dataframes
Managing CSV files and data handling
Applying linear regression models in R
Understanding and utilizing confusion matrices
Implementing random forest algorithms in R
Performing analytics tasks using R
Manipulating and transforming strings in R

1200+ customers in 80 countries

Use Adaface tests trusted by recruitment teams globally. Adaface skill assessments measure on-the-job skills of candidates, providing employers with an accurate tool for screening potential hires.

Get started for free

Preview questions

Non-googleable questions

We have a very high focus on the quality of questions that test for on-the-job skills. Every question is non-googleable and we have a very high bar for the level of subject matter experts we onboard to create these questions. We have crawlers to check if any of the questions are leaked online. If/ when a question gets leaked, we get an alert. We change the question for you & let you know.

How we design questions

These are just a small sample from our library of 15,000+ questions. The actual questions on this R Online Test will be non-googleable.

🧐 Question
Medium Applying Functions Data frames Functions Math	Solve
Consider the following R code: This script defines a function apply_fun that calculates the mean of a vector and adds it to the standard deviation of the vector. The apply function is then used to apply this function to each column of the data frame df. What will be the value of result after the script is run?
Medium Dataframe Transform Reshape	Solve
Review the following Dataframe 'bazinga': Which of the following commands would turn it into the Dataframe shown below:
Medium Matrix Manipulation Matrices Lists	Solve
Consider the following pseudo code: What will be the state of list_of_matrices after running the script?
Easy Registration Queue Logic Queues Sorting By Custom Order	Solve
We want to register students for the next semester. All students have a receipt which shows the amount pending for the previous semester. A positive amount (or zero) represents that the student has paid extra fees, and a negative amount represents that they have pending fees to be paid. The students are in a queue for the registration. We want to arrange the students in a way such that the students who have a positive amount on the receipt get registered first as compared to the students who have a negative amount. We are given a queue in the form of an array containing the pending amount. For example, if the initial queue is [20, 70, -40, 30, -10], then the final queue will be [20, 70, 30, -40, -10]. Note that the sequence of students should not be changed while arranging them unless required to meet the condition. ⚠️⚠️⚠️ Note: - The first line of the input is the length of the array. The second line contains all the elements of the array. - The input is already parsed into an array of "strings" and passed to a function. You will need to convert string to integer/number type inside the function. - You need to "print" the final result (not return it) to pass the test cases. For the example discussed above, the input will be: 5 20 70 -40 30 -10 Your code needs to print the following to the standard output: 20 70 30 -40 -10
Medium Visitors Count Strings Logic String Parsing Character Counting	Solve
A manager hires a staff member to keep a record of the number of men, women, and children visiting the museum daily. The staff will note W if any women visit, M for men, and C for children. You need to write code that takes the string that represents the visits and prints the count of men, woman and children. The sequencing should be in decreasing order. Example: Input: WWMMWWCCC Expected Output: 4W3C2M Explanation: ‘W’ has the highest count, then ‘C’, then ‘M’. ⚠️⚠️⚠️ Note: - The input is already parsed and passed to a function. - You need to "print" the final result (not return it) to pass the test cases. - If the input is- “MMW”, then the expected output is "2M1W" since there is no ‘C’. - If any of them have the same count, the output should follow this order - M, W, C.

	🧐 Question	🔧 Skill
	Medium Applying Functions Data frames Functions Math	3 mins R	Solve
Consider the following R code: This script defines a function apply_fun that calculates the mean of a vector and adds it to the standard deviation of the vector. The apply function is then used to apply this function to each column of the data frame df. What will be the value of result after the script is run?
	Medium Dataframe Transform Reshape	3 mins R	Solve
Review the following Dataframe 'bazinga': Which of the following commands would turn it into the Dataframe shown below:
	Medium Matrix Manipulation Matrices Lists	3 mins R	Solve
Consider the following pseudo code: What will be the state of list_of_matrices after running the script?
	Easy Registration Queue Logic Queues Sorting By Custom Order	30 mins Coding	Solve
We want to register students for the next semester. All students have a receipt which shows the amount pending for the previous semester. A positive amount (or zero) represents that the student has paid extra fees, and a negative amount represents that they have pending fees to be paid. The students are in a queue for the registration. We want to arrange the students in a way such that the students who have a positive amount on the receipt get registered first as compared to the students who have a negative amount. We are given a queue in the form of an array containing the pending amount. For example, if the initial queue is [20, 70, -40, 30, -10], then the final queue will be [20, 70, 30, -40, -10]. Note that the sequence of students should not be changed while arranging them unless required to meet the condition. ⚠️⚠️⚠️ Note: - The first line of the input is the length of the array. The second line contains all the elements of the array. - The input is already parsed into an array of "strings" and passed to a function. You will need to convert string to integer/number type inside the function. - You need to "print" the final result (not return it) to pass the test cases. For the example discussed above, the input will be: 5 20 70 -40 30 -10 Your code needs to print the following to the standard output: 20 70 30 -40 -10
	Medium Visitors Count Strings Logic String Parsing Character Counting	30 mins Coding	Solve
A manager hires a staff member to keep a record of the number of men, women, and children visiting the museum daily. The staff will note W if any women visit, M for men, and C for children. You need to write code that takes the string that represents the visits and prints the count of men, woman and children. The sequencing should be in decreasing order. Example: Input: WWMMWWCCC Expected Output: 4W3C2M Explanation: ‘W’ has the highest count, then ‘C’, then ‘M’. ⚠️⚠️⚠️ Note: - The input is already parsed and passed to a function. - You need to "print" the final result (not return it) to pass the test cases. - If the input is- “MMW”, then the expected output is "2M1W" since there is no ‘C’. - If any of them have the same count, the output should follow this order - M, W, C.

	🧐 Question	🔧 Skill	💪 Difficulty	⌛ Time
	Applying Functions Data frames Functions Math	R	Medium	3 mins	Solve
Consider the following R code: This script defines a function apply_fun that calculates the mean of a vector and adds it to the standard deviation of the vector. The apply function is then used to apply this function to each column of the data frame df. What will be the value of result after the script is run?
	Dataframe Transform Reshape	R	Medium	3 mins	Solve
Review the following Dataframe 'bazinga': Which of the following commands would turn it into the Dataframe shown below:
	Matrix Manipulation Matrices Lists	R	Medium	3 mins	Solve
Consider the following pseudo code: What will be the state of list_of_matrices after running the script?
	Registration Queue Logic Queues Sorting By Custom Order	Coding	Easy	30 mins	Solve
We want to register students for the next semester. All students have a receipt which shows the amount pending for the previous semester. A positive amount (or zero) represents that the student has paid extra fees, and a negative amount represents that they have pending fees to be paid. The students are in a queue for the registration. We want to arrange the students in a way such that the students who have a positive amount on the receipt get registered first as compared to the students who have a negative amount. We are given a queue in the form of an array containing the pending amount. For example, if the initial queue is [20, 70, -40, 30, -10], then the final queue will be [20, 70, 30, -40, -10]. Note that the sequence of students should not be changed while arranging them unless required to meet the condition. ⚠️⚠️⚠️ Note: - The first line of the input is the length of the array. The second line contains all the elements of the array. - The input is already parsed into an array of "strings" and passed to a function. You will need to convert string to integer/number type inside the function. - You need to "print" the final result (not return it) to pass the test cases. For the example discussed above, the input will be: 5 20 70 -40 30 -10 Your code needs to print the following to the standard output: 20 70 30 -40 -10
	Visitors Count Strings Logic String Parsing Character Counting	Coding	Medium	30 mins	Solve
A manager hires a staff member to keep a record of the number of men, women, and children visiting the museum daily. The staff will note W if any women visit, M for men, and C for children. You need to write code that takes the string that represents the visits and prints the count of men, woman and children. The sequencing should be in decreasing order. Example: Input: WWMMWWCCC Expected Output: 4W3C2M Explanation: ‘W’ has the highest count, then ‘C’, then ‘M’. ⚠️⚠️⚠️ Note: - The input is already parsed and passed to a function. - You need to "print" the final result (not return it) to pass the test cases. - If the input is- “MMW”, then the expected output is "2M1W" since there is no ‘C’. - If any of them have the same count, the output should follow this order - M, W, C.

Get started for free

Preview questions

With Adaface, we were able to optimise our initial screening process by upwards of 75%, freeing up precious time for both hiring managers and our talent acquisition team alike!

Brandon Lee, Head of People, Love, Bonito

It's very easy to share assessments with candidates and for candidates to use. We get good feedback from candidates about completing the tests. Adaface are very responsive and friendly to deal with.

Kirsty Wood, Human Resources, WillyWeather

We were able to close 106 positions in a record time of 45 days! Adaface enables us to conduct aptitude and psychometric assessments seamlessly. My hiring managers have never been happier with the quality of candidates shortlisted.

Amit Kataria, CHRO, Hanu

We evaluated several of their competitors and found Adaface to be the most compelling. Great library of questions that are designed to test for fit rather than memorization of algorithms.

Swayam Narain, CTO, Affable

Why you should use Pre-employment R Online Test?

The R Online Test makes use of scenario-based questions to test for on-the-job skills as opposed to theoretical knowledge, ensuring that candidates who do well on this screening test have the relavant skills. The questions are designed to covered following on-the-job aspects:

Working with Vectors
Performing operations on Matrices
Analyzing Dataframes
Importing and exporting CSV files
Implementing Linear regression models
Interpreting Confusion matrices
Applying Random Forest algorithms
Utilizing Analytics techniques
Performing String Manipulation

Once the test is sent to a candidate, the candidate receives a link in email to take the test. For each candidate, you will receive a detailed report with skills breakdown and benchmarks to shortlist the top candidates from your pool.

What topics are covered in the R Online Test?

Vectors: Vectors in R are one-dimensional arrays that can hold elements of any type. They are used to store and perform operations on a homogeneous set of data. Measuring this skill will assess a candidate's understanding of vector creation, indexing, and various vector operations.

Matrices: Matrices in R are two-dimensional arrays that store elements of the same type. This skill will evaluate a candidate's ability to create and manipulate matrices, perform matrix operations such as addition, subtraction, and multiplication, and apply matrix operations in solving problems.

Dataframes: Dataframes are tabular data structures in R that store data in rows and columns. Assessing a candidate's knowledge of dataframes will ascertain their proficiency in data manipulation, including merging, filtering, and transforming data, as well as their understanding of data reshaping.

CSV Handling: CSV (Comma-Separated Values) handling is the ability to read, write, and manipulate data stored in CSV format. This skill is crucial in real-life scenarios where data is often exchanged and stored in CSV files. Assessing this skill will determine a candidate's proficiency in loading, saving, and performing data transformations on CSV files in R.

Linear regression: Linear regression is a statistical technique used to analyze the relationship between a dependent variable and one or more independent variables. Measuring a candidate's understanding of linear regression will assess their ability to fit linear regression models, interpret model outputs, and make predictions using the models.

Confusion matrix: A confusion matrix is a table that represents the performance of a classification algorithm. Measuring a candidate's knowledge of confusion matrices will evaluate their understanding of key metrics such as accuracy, precision, recall, and F1 score, and their ability to analyze and interpret classification results.

Random Forest: Random Forest is an ensemble learning method used for classification and regression. Assessing this skill will gauge a candidate's ability to apply the Random Forest algorithm, understand the underlying principles, tune the model parameters, and evaluate its performance using appropriate statistical measures.

Analytics with R: Analytics with R involves using R programming language and its associated packages to perform data analysis, visualization, and statistical modeling. Evaluating this skill will determine a candidate's proficiency in utilizing R's analytical capabilities, applying statistical techniques, and generating insights from data.

String Manipulation: String manipulation refers to the process of modifying, extracting, or manipulating textual data in R. This skill assessment will measure a candidate's ability to perform tasks such as concatenating strings, replacing patterns, extracting substrings, and applying regular expressions on character data to solve data processing and manipulation challenges.

Full list of covered topics

The actual topics of the questions in the final test will depend on your job description and requirements. However, here's a list of topics you can expect the questions for R Online Test to be based on.

Vectors

Matrices

Dataframes

CSV Handling

Linear Regression

Confusion Matrix

Random Forest

Analytics with R

String Manipulation

Vector Operations

Matrix Operations

Dataframe Manipulation

Reading and Writing CSV Files

Simple Linear Regression

Multiple Linear Regression

Interpreting Confusion Matrices

Random Forest Algorithm

Classification and Regression Trees (CART)

Clustering Algorithms

Data Exploration and Visualization

Data Cleaning and Preprocessing

Statistical Analysis in R

Text Manipulation and Extraction

Regular Expressions

String Matching

Missing Data Handling

Data Aggregation and Reshaping

Handling Time Series Data

Dimensionality Reduction Techniques

Statistical Modeling Techniques in R

Handling Outliers and Anomalies

Data Mining and Machine Learning

Feature Selection and Variable Importance

Model Evaluation and Validation

Performance Measurement Metrics

Cross-Validation Techniques

Hyperparameter Tuning

Data Imputation Techniques

Web Scraping and APIs in R

Databases and SQL Integration in R

Geospatial Analysis and Mapping

Data Visualization with ggplot2

Statistical Tests and Hypothesis Testing

Time Series Forecasting

Natural Language Processing (NLP)

Image Processing and Computer Vision

Big Data Analytics with R

Deep Learning and Neural Networks

Parallel Computing and Performance Optimization

R Shiny App Development

Reproducible Research with R Markdown

Version Control with Git and GitHub

Collaborative Data Science with RStudio

Scalable Analytics using SparkR

Cloud Computing and R Integration

Creating Interactive Dashboards with Shiny

Advanced Data Visualization Techniques

Graph Analysis and Social Network Data

Bayesian Statistics and Inference in R

What roles can I use the R Online Test for?

Data Scientist
Data Analyst
Core R Developer
Core R Programmer
Python Developer
Machine Learning Engineer

How is the R Online Test customized for senior candidates?

For intermediate/ experienced candidates, we customize the assessment questions to include advanced topics and increase the difficulty level of the questions. This might include adding questions on topics like

Mastering data visualization
Implementing machine learning algorithms
Applying data mining techniques
Working with time series data
Performing data cleaning and preprocessing
Understanding statistical inference
Applying optimization techniques
Applying natural language processing
Utilizing parallel computing

The coding question for experienced candidates will be of a higher difficulty level to evaluate more hands-on experience.

Preview this test

View sample scorecard

Try the most advanced candidate assessment platform

ChatGPT Protection

Non-googleable Questions

Web Proctoring

IP Proctoring

Webcam Proctoring

MCQ Questions

Coding Questions

Typing Questions

Personality Questions

Custom Questions

Ready-to-use Tests

Custom Tests

Custom Branding

Bulk Invites

Public Links

ATS Integrations

Multiple Question Sets

Custom API integrations

Role-based Access

Priority Support

GDPR Compliance

Screen candidates in 3 easy steps

Pick a test from over 500+ tests

The Adaface test library features 500+ tests to enable you to test candidates on all popular skills- everything from programming languages, software frameworks, devops, logical reasoning, abstract reasoning, critical thinking, fluid intelligence, content marketing, talent acquisition, customer service, accounting, product management, sales and more.

Invite your candidates with 2-clicks

Make informed hiring decisions

Get started for free

Preview questions

Have questions about the R Hiring Test?

What is R Online Test?

The R Online Test is designed to evaluate the proficiency of candidates in the R programming language. It is used by recruiters to screen potential hires for roles that require expertise in data analysis and statistical computing.

Can I combine the R Online Test with data science questions?

Yes, you can request a custom test that includes both R programming and data science questions. Learn more about our Data Science Assessment Test.

What skills are evaluated in the R Online Test?

This test covers Vectors, Matrices, Dataframes, CSV Handling, Linear Regression, Confusion Matrix, Random Forest, Analytics with R, and String Manipulation. For senior roles, it assesses skills like data visualization, machine learning algorithms, data mining techniques, and more.

How to use the R Online Test in my hiring process?

Use it as a pre-screening tool early in your recruitment process. Add the test link to your job post or invite candidates via email to find skilled candidates faster.

Can I test R and SQL together in a test?

Yes, you can combine R and SQL in a single test. This is recommended for roles requiring both programming and database skills. Check out our Python & SQL Test for an example.

What are the main data analysis tests?

Key tests in this category include:

Can I combine multiple skills into one custom assessment?

Yes, absolutely. Custom assessments are set up based on your job description, and will include questions on all must-have skills you specify. Here's a quick guide on how you can request a custom test.

Do you have any anti-cheating or proctoring features in place?

We have the following anti-cheating features in place:

Non-googleable questions
IP proctoring
Screen proctoring
Web proctoring
Webcam proctoring
Plagiarism detection
Secure browser
Copy paste protection

Read more about the proctoring features.

How do I interpret test scores?

The primary thing to keep in mind is that an assessment is an elimination tool, not a selection tool. A skills assessment is optimized to help you eliminate candidates who are not technically qualified for the role, it is not optimized to help you find the best candidate for the role. So the ideal way to use an assessment is to decide a threshold score (typically 55%, we help you benchmark) and invite all candidates who score above the threshold for the next rounds of interview.

What experience level can I use this test for?

Each Adaface assessment is customized to your job description/ ideal candidate persona (our subject matter experts will pick the right questions for your assessment from our library of 10000+ questions). This assessment can be customized for any experience level.

Does every candidate get the same questions?

Yes, it makes it much easier for you to compare candidates. Options for MCQ questions and the order of questions are randomized. We have anti-cheating/ proctoring features in place. In our enterprise plan, we also have the option to create multiple versions of the same assessment with questions of similar difficulty levels.

I'm a candidate. Can I try a practice test?

No. Unfortunately, we do not support practice tests at the moment. However, you can use our sample questions for practice.

What is the cost of using this test?

You can check out our pricing plans.

Can I get a free trial?

Yes, you can sign up for free and preview this test.

I just moved to a paid plan. How can I request a custom assessment?

Here is a quick guide on how to request a custom assessment on Adaface.

View sample scorecard

Along with scorecards that report the performance of the candidate in detail, you also receive a comparative analysis against the company average and industry standards.

View sample scorecard