Data Science With R Programming — Coding Interview Questions

Data science is a vast field where specialized knowledge is more valued. While knowing a few programming concepts and languages help you write better code, knowing everything about one language can help you stand out among your peers. Python is the most popular programming language that many software developers and IT professionals use, so mastering it will not create the impact you wish. Instead, opting for something like R would do the trick.

R is especially useful when working with data wrangling, statistics, and machine learning. It's an open-source programming language that makes these tasks quick and easy. From forecast analysis to data manipulation, everything can be done with R. After you get trained in R, you have to clear a few rounds of interviews to get a job. So the first thing you need to clear the interviews is training on R.

Let's look at some common interview questions for this position.

Top 13 R Programming Interview Questions

When Do You Use Python, And When Do You Use R?

R has inbuilt functionality for data analysis, so using the R language for any task related to data analysis would make sense. You can use python for any other job that doesn't require data analysis.

What Are The Advantages Of R?

These are some well-known advantages of R:

• It is an open source
• Easy to perform data wrangling
• There are a variety of packages available
• It is independent of any platform
• You can perform machine-learning operations

What Is Recycling Of Elements In A Vector?

When two vectors need to be of the same length, R starts recycling the shorter vector until it's as long as the second vector. This entire process is called element recycling.

How Many Data Structures Are Available In R Programming?

There are two data structures available in R programming; homogeneous and heterogeneous. As the name suggests, homogeneous data structures include objects like an array, matrix, and vector. Heterogeneous data structures, on the other hand, include things like data lists and frames.

What Is Lazy Function Evaluation In R?

Lazy function evaluation is a function in R that delays an expressions evaluation function until the value is immediately needed. This function makes sure that there are no repeated evaluations, increasing the efficiency of the program.

Explain Data Import In R.

Data import in R starts with the user typing the commands in the command Rcmdr into the console. Then the data can be imported in 3 ways:

• You select the data set in the dialog box or by entering the name of the required data set.
• The data can also be directly entered using the editor of R commander. It will look something like this: Data -> New Data set. If your data set is too large, you will have trouble importing.
• Using URL or plain text file (ASCII)

How Does R Language Represent Missing Values And Impossible Values?

The missing values in R are represented by capital letters NA (not available). In comparison, impossible values in R are represented by NaN (not a number).

How Will You Perform Decision Making In R?

There is little difference between performing decision-making in R and other programming languages. Here are the 3 decision-making statements to choose from

• If statement
• If.else statement
• Switch statement
  

Which Function Will You Use To Find Out Whether The Means Of 2 Groups Is Equal Or Not?

You will perform the t-test function to determine whether the 2 groups are equal.

How To Make Predictive Analysis Using R?

To make a predictive analysis, you need historical data to find patterns. Then, you can predict the future by analyzing those historical patterns and facts. Time series analysis and non-linear least squares are examples of the methods used in predictive analysis.

What Are The Different Types Of Data In R?

There are 5 basic types of data in R:

• Character
• Numeric
• Integer
• Complex
• Logical

What Does Class () Do In R?

The values of the class attribute of an R object are returned using the class () function in R.

What Are Data Frames In R?

Data frames in R are data objects used to store tabular data. Often these data frames are interpreted as matrices where each column represents different types of data. So a data frame usually consists of three principal components; data, columns, and rows.

Conclusion

Cracking a data science interview with R programming coding is easier than one might think. All you need to do is prepare with all the technical knowledge you have and prepare with some common interview questions.