Lee Baker - Practical Data Cleaning

Practical Data Cleaning

19 Essential Tips to Scrub Your Dirty Data

Practical Data Cleaning (5th Edition)

By Lee Baker

Copyright 2019 Lee Baker

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Preface

T he success of the first 4 editions of Practical Data Cleaning has been overwhelming and has come as a bit of a shock there have now been thousands of downloads. I had no idea it would be so popular!

Firstly, a huge thank you to all of you that took the time to download and read it. I hope you found it useful and got something of real value out of it.

Secondly, I wish to thank all of you that have interrupted your busy schedules to get in touch. Your words of support have touched me and inspired me to continue writing.

Of all of the feedback Ive received, by far the most common request is for me to cover the subject material in much greater depth, so Ive created The Hive an online portal where you can take video courses about Data Science drawing on some of my 20+ years of experience.

To celebrate the launch of The Hive , Ive created a sister course Data Wrangling 19 Essential Tips to accompany this book. The video course goes into more detail than the book, and you can get it completely FREE !

There are lots of courses available in The Hive and many more planned, and you can get FREE ENTRY right now!

I hope youll take a few moments to check out our video courses, and I look forward to seeing you there!

You can get access to the Data Wrangling 19 Essential Tips video course right now by following this link:

https://www.chi2innovations.com/the-hive/hive-courses/data-wrangling-19-essential-tips/

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Introduction

Dont Panic !!!

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D ata cleaning is a waste of time.

If the data had been collected properly in the first place there wouldnt be any cleaning to do, and you wouldnt now be faced with the prospect of weeks of cleaning to get your dataset analysis-ready.

Worse still, your boss wont understand why your analysis report isnt on his desk yet, a mere 48 hours after hes asked for it. Bless him, he doesnt understand he thinks that cleaning data is just about clicking a few buttons in Excel and ta da! its all done. Even a monkey can do that, right?

And for good reason you wont get any help from statistics books either. Data is messy and cleaning it can be difficult, time-consuming and costly. Not to mention its the least sexy thing you can do with a dataset.

Yet youve still got to do it, because, well, someone has to...

But it doesnt have to be so difficult. If youre organised and follow a few simple rules your data cleaning processes can be simple, fast and effective.

Not to mention fun!

Well, not fun exactly, just not quite as coma-inducing.

This book (now in its 5th Edition!) explains the 19 most important tips about data cleaning with a focus on understanding your data, how to work with it, choose the right ways to analyse it, select the correct tools and how to interpret the results to get your data clean in double quick time.

Now it doesnt matter whether youre a scientist or an entrepreneur, in academia or in business, if youre collecting data to try to answer some questions then you need to understand the fundamentals .

Youll likely spend a lot of time observing, measuring, counting, classifying and quantifying what you see, and once youve collected your data youre going to have to analyse it.

But lets not get too far ahead of ourselves...

Before you can get any answers youre going to have to:

• Collect
• Record & Store
• Clean & Classify

The textbooks tend not to dwell on the practical issues too much because, well, to be honest, it can get quite messy, but these are vitally important steps and you really do need to know how to do them properly if youre going to get the most out of your data .

So lets rewind to the beginning and see what we can do to get you off to a good start...

Here are 3 rules to start off with:

1. Dont Panic !!!
2. Start thinking about the data before you start collecting it
3. Make a personal vow to understand the basics of data

As a quick reminder, you are free to share this eBook with anyone as long as you dont change it or charge for it.

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T here is a Resources page that accompanies this book, where you will find reviews and links to other books , blogs , video courses and all sorts of other useful stuff.

This page is updated regularly so youll always know where to find the best the web has to offer.

Visit the resources page here:

• http://bit.ly/2RbRc8G

Chapter 1: Data Collection