Gardener - The Essential R Reference

The Essential R Reference

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Copyright 2013 by Mark Gardener

Published by John Wiley & Sons, Inc., Indianapolis, Indiana

Published simultaneously in Canada

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ISBN: 978-1-118-39138-9 (ebk)

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There's only one corner of the universe you can be certain of improving, and that's your own self.

Aldous Huxley

Mark Gardener ( http://www.gardenersown.co.uk ) is an ecologist, lecturer, and writer working in the UK. He has a passion for the natural world and for learning new things. Originally he worked in optics, but returned to education in 1996 and eventually gained his doctorate in ecology and evolutionary biology. This work involved a lot of data analysis and he became interested in R as a tool to help in research. He is currently self-employed and runs courses in ecology, data analysis, and R for a variety of organizations. Mark lives in rural Devon with his wife Christine (a biochemist) and still enjoys the natural world and learning new things.

Richard Rowe started his professional life as a physicist, but switched fields to earn a PhD in insect behavior. He has taught data analysis courses, mainly to biologists, at Canterbury, then James Cook University, since 1982. He has worked with R since 1997 when a friend forced a very early copy onto him. The R system has exponentially improved over the past decade, and in light of the fact that Richards individual capacity is more linear, he retired in 2011 but keeps his hand in data-analysis consultancies and master-class workshops regularly (the best way to learn is to teach). Based on life, his belief is that ecological and behavioral data is usually the dirtiest and most ill-behaved, and hence the most fun to explore for pattern. His other hobby is dragonfly biology.

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First of all my thanks go out to the R project team and the many authors and programmers who work tirelessly to make this a peerless program. I would also like to thank my wife, Christine, who has had to put up with me during this entire process, and in many senses became an R-widow! Thanks to Wiley, for helping this book become a reality, especially Carol Long and Victoria Swider. I couldnt have done it without you. Thanks also to Richard Rowe, the technical reviewer, who first brought my attention to R and its compelling (and rather addictive) power.

Last but not least, thanks to the R community in general. I learned to use R largely by trial and error and using the vast wealth of knowledge that is in this community. I hope that this book is a worthwhile addition to the R knowledge base and that it will prove useful to all users of R.

Mark Gardener

R is rapidly becoming the de facto standard among professionals, and is used in every conceivable discipline from science and medicine to business and engineering. R is more than just a computer program; it is a statistical programming environment and language. R is free and open source and is, therefore, available to everyone with a computer.

R is a language with its own vocabulary and grammar. To make R work for you, you communicate with the computer using the language of R and tell it what to do. You accomplish this by typing commands directly into the program. This means that you need to know some of the words of the language and how to put them together to make a sentence that R understands. This book aims to help with this task by providing a dictionary of words that R understands.