De Vries Andrie - R for dummies [making everything easier!; Learn to: use R for data analysis and processing, write functions and scripts for repeatable analysis, create high-quality charts and graphics, perform

R For Dummies

by Andrie de Vries and Joris Meys

R For Dummies

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ISBN 978-1-119-96284-7 (paperback); ISBN 978-1-119-96312-7 (ebook); ISBN 978-1-119-96313-4 (ebook); ISBN 978-1-119-96314-1 (ebook)

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About the Authors

Andrie de Vries: Andrie started to use R in 2009 to analyze survey data, and he has been continually impressed by the ability of the open-source community to innovate and create phenomenal software. Andrie is director of PentaLibra Limited, a boutique market-research firm specializing in surveys and statistical analysis. He has contributed two R packages to CRAN and is developing several packages to make the analysis and reporting of survey data easier. He also is actively involved in the development of LimeSurvey, the open-source survey-management system. To maintain equilibrium in his life, Andrie is working toward a yoga teacher diploma at the Krishnamacharya Healing and Yoga Foundation.

Joris Meys, MSc: Joris is a statistical consultant and R programmer in the Department of Mathematical Modeling, Statistics, and Bioinformatics at Ghent University (Belgium). After earning a masters degree in biology, he worked for six years in environmental research and management before starting an advanced masters degree in statistical data analysis. Joris writes packages for both specific projects and general implementation of methods developed in his department, and he is the maintainer of several packages on R-Forge. He has co-authored a number of scientific papers as a statistical expert. To balance science with culture, Joris spends most of his spare time playing saxophone in a couple of local bands.

Dedication

This book is for my wife, Annemarie, because of her encouragement, support, and patience. And for my 9-year-old niece, Tanya, who is really good at math and kept reminding me that the deadline for this book was approaching!

Andrie de Vries

For my mother, because she made me the man I am. And for Granny, because she rocks!

Joris Meys

Authors Acknowledgments

This book is possible only because of the tremendous support we had from our editorial team at Wiley. In particular, thank you to Elizabeth Kuball for her patient and detailed editing and gentle cajoling, and to Sara Shlaer for pretending not to hear the sound of missed deadlines. Thank you to Kathy Simpson for teaching us how to write in Dummies style, and to Chris Katsaropoulos for getting us started.

Thank you to our technical editor, Gavin Simpson, for his thorough reading and many helpful comments.

Thank you to the R core team for creating R, for maintaining CRAN, and for your dedication to the R community in the form of mailing lists, documentation, and seminars. And thank you to the R community for creating thousands of useful packages, writing blogs, and answering questions.

In this book, we use several packages by Hadley Wickham, whose contribution of ggplot graphics and other helpful packages like plyr continues to be an inspiration.

While writing this book we had very helpful support from a large number of contributors to the R tag at Stack Overflow. Thank you to James (JD) Long, David Winsemius, Ben Bolker, Joshua Ulrich, Kohske Takahashi, Barry Rowlingson, Roman Lutrik, David Purdy, Nick Sabbe, Joran Elias, Brandon Bertelsen, Michael Sumner, Ian Fellows, Dirk Eddelbuettel, Simon Urbanek, Gabor Grotendieck, and everybody else who continue to make Stack Overflow a great resource for the R community.

From Andrie: Thank you to the large number of people who have influenced my choices. Professor Bruce Hardie at London Business School made a throwaway comment during a lecture in 2004 that first made me aware of R; his pragmatic approach to making statistics relevant to marketing decision makers was inspirational. Gary Bennett at Logit Research has been very helpful with his advice and a joy to work with. Paul Hutchings at Kindle Research was very supportive in the early stages of setting up my business.