Data wrangling is a task of great importance in data analysis. Data wrangling, is the process of importing, cleaning and transforming raw data into actionable information for analysis. It is a time-consuming process which is estimated to take about 60-80% of analyst’s time. In this series we will go through this process. It will be […]

# Exercises

## iPlots exercises

INTRODUCTION iPlots is a package which provides interactive statistical graphics, written in Java. You can find many interesting plots such as histograms, barcharts, scatterplots, boxplots, fluctuation diagrams, parallel coordinates plots and spineplots. The amazing part is that all of these plots support querying, linked highlighting, color brushing, and interactive changing of parameters. Before proceeding, please […]

## Volatility modelling in R exercises (Part-2)

This is the second part of the series on volatility modelling. For other parts of the series follow the tag volatility. In this exercise set we will use the dmbp dataset from part-1 and extend our analysis to GARCH (Generalized Autoregressive Conditional Heteroscedasticity) models. Answers to the exercises are available here. Exercise 1 Load the […]

## Hacking statistics or: How I Learned to Stop Worrying About Calculus and Love Stats Exercises (Part-1)

Statistics are often taught in school by and for people who like Mathematics. As a consequence, in those class emphasis is put on leaning equations, solving calculus problems and creating mathematics models instead of building an intuition for probabilistic problems. But, if you read this, you know a bit of R programming and have access […]

## Data Visualization with googleVis exercises part 5

Candlestick, Pie, Gauge, Intensity Charts In the fifth part of our journey we will meet some special but more and more usable types of charts that googleVis provides. More specifically you will learn about the features of Candlestick, Pie, Gauge and Intensity Charts. Read the examples below to understand the logic of what we are […]

## Data Manipulation with data.table (part -2)

In the last set of exercise of data.table ,we saw some interesting features of data.table .In this set we will cover some of the advanced features like set operation ,join in data.table.You should ideally complete the first part before attempting this one . Answers to the exercises are available here. If you obtained a different […]

## Working with the xlsx package Exercises (part 2)

This exercise set provides (further) practice in writing Excel documents using the xlsx package as well as importing and general data manipulation. Specifically we have loops in order for you to practice scaling. A previous exercise set focused on writing a simple sheet with the same package, see here. We will use a subset of […]

## Volatility modelling in R exercises (Part-1)

Volatility modelling is typically used for high frequency financial data. Asset returns are typically uncorrelated while the variation of asset prices (volatility) tends to be correlated across time. In this exercise set we will use the rugarch package (package description: here) to implement the ARCH (Autoregressive Conditional Heteroskedasticity) model in R. Answers to the exercises […]

## Data Visualization with googleVis exercises part 4

Adding Features to your Charts We saw in the previous charts some basic and well-known types of charts that googleVis offers to users. Before continuing with other, more sophisticated charts in the next parts we are going to “dig a little deeper” and see some interesting features of those we already know. Read the examples […]

## Protected: Bonus: Improve Data Consistency With Vapply()

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