In this exercise we cover the basics on selecting and extracting data using queries. We add a few other materials into it. This should prepare you for the next exercise: Basic Decision Tree. The purpose of this is to give you the 20 percent of the tools to get 80 percent of work done. You […]

# Exercises (beginner)

## Descriptive Analytics-Part 5: Data Visualisation (Continuous variables)

Descriptive Analytics is the examination of data or content, usually manually performed, to answer the question “What happened?”. In order to be able to solve this set of exercises you should have solved the part 0, part 1, part 2,part 3, and part 4 of this series but also you should run this script which […]

## Model Evaluation Exercises 1

We are committed to bringing you 100% authentic exercise sets. We even try to include as different datasets as possible to give you an understanding of different problems. No more classifying Titanic dataset. R has tons of datasets in its library. This is to encourage you to try as many datasets as possible. We will […]

## Scripting Loops exercises Vol.2

[For this exercise, first write down your answer, without using R. Then, check your answer using R.] Answers to the exercises are available here. Exercise 1 Using the following variables: x=1 i=c(1:10) For this exercise, write a for() loop that increments x by two for each i. Exercise 2 Using the following variables: x=1 y=40 […]

## Frequency and chi-square test for independence Exercises

In this exercise, we cover some basics on frequency tables. We also briefly look at chi-square test for independence to find relationships of two variables. Before proceeding, it might be helpful to look over the help pages for the table, summary, and margin.table functions. Answers to the exercises are available here. If you obtained a […]

## Data frame exercises Vol. 2

[In the exercises below we cover the basics of data frames.] Answers to the exercises are available here. Exercise 1 Consider two vectors: x=seq(1,43,along.with=Id) y=seq(-20,0,along.with=Id) Create a data.frame df: >df Id Letter x y 1 1 a 1.000000 -20.000000 2 1 b 4.818182 -18.181818 3 1 c 8.636364 -16.363636 4 2 a 12.454545 -14.545455 5 […]

## String Manipulation – Exercises

In this set of exercises we will practice functions that enable us to manipulate strings.You can find more about string manipulation functions in Handling and Processing Strings in R e-book. Answers to the exercises are available here. If you have different solution, feel free to post it. Exercise 1 Load text from the file and […]

## Descriptive Analytics-Part 4 : Data Manipulation

Descriptive Analytics is the examination of data or content, usually manually performed, to answer the question “What happened?”. In order to be able to solve this set of exercises you should have solved the part 0, part 1, part 2 ,and part 3 of this series but also you should run this script which contain […]

## Nonparametric Tests Exercises

In this set of exercises you will be presented with real-life problems in marketing. Your task will be to choose appropriate nonparametric statistical technique and solve the problem using appropriate R functions. Answers to the exercises are available here. Exercise 1 A company wants to learn if sales income is equaly distributed among the stores. […]

## Generating Data Exercises

Let’s make data R is good a making simulated data sets. These data sets are useful for learning programming. Instead of having to spend all your time cleaning up your data you have data ready to use for learning how to program. The data that will be generated here will be about cats, toys and […]