Why these books are unique

If you are looking for a dense, equation-ridden books that cost a fortune and sound like they were written in foreign languages, you have plenty of choices. My books are different for several reasons:

1. Evidence-based: These books will show you how to examine the evidence directly. What is it? How big is it? And what does it mean?
2. Meaningful interpretation: As a highly-published researcher, I am aware of the temptation to pass off statistically significant results as meaningful. These books will help you interpret your results in metrics that are meaningful to nonspecialists.
3. Jargon-free: Teaching in a city where English is the second-language (Hong Kong) forced me to be simple and clear.  These books were to help you get up the learning curve with as little fuss as possible. Their tone is light and the concepts are easy to grasp.

What is your time worth?

There are few things more depressing than committing to a research project that yields nothing. If you could be told in advance the probability that your project would succeed, how much would you pay for that information? 

To sign up for my Research Methods course would cost you thousands in fees. To teach yourself the lessons distilled in these books would require months or years of study. However, I’m offering these books for just $15.99 each.  Even better, you can get all three books for just $19.99—a saving of more than $20.00!

I’m not selling these books to fund my retirement and there are no margins going to middlemen. I just want to help you do better research. These are the manuals I wish I had when I was starting out. Whether you are a doctoral student or a professor, they will help you do research that matters.

Please note: these ebooks are available as a PDF download while the three-book combo for $19.99 comes in 3 formats: PDF, ePub (read it on your phone), and MOBI (read it in your Kindle reader).

What readers saying about The Essential Guide to Effect Sizes

“Paul Ellis writes with a light touch, explains well, and uses numerous practical examples. He focuses on the issues that are central to the statistical changes now sweeping many disciplines. The Essential Guide to Effect Sizes is a highly readable, highly practical book. It will be invaluable to anyone who wishes to contribute to – or even just understand – the research of the future.” 
~Geoff Cumming, Emeritus Professor, La Trobe University

“Assessing the substantive significance of research is essential for both scientific progress and practical implications. This authoritative and well-written book gives relevant examples of key issues and offers practical guidelines for assessing the importance of research findings. The book concludes with clear recommendations for designing and carrying out good research and for assessing and reporting research findings.” 
~ William H. Starbuck, Professor Emeritus, New York University

“Excellent book!” ~Andreas Schwab, Iowa State University

“This book is a good read, not at all heavy on technical jargon or formulas. Well-written and informative. Heartily recommended.” 
~John V. Karavitis,

“I thoroughly enjoyed The Essential Guide to Effect Sizes and read it twice. Later I incorporated this book into a module in my advanced stats class for doctoral students. The topic was perfect for them, and the comfortable writing style made the book a delight to read. As noted by the author, some people write to impress and others to instruct. This book is for instruction.” 
~Wm A. Sands, Ph.D.

“The Essential Guide to Effect Sizes is a very thorough, well explained guide to assuring levels of power during the design stage of a research effort. The importance of such an analysis seems to be missing in most graduate level statistics courses, but it can serve a researcher very well.” ~Amazon reviewer

“Before reading the book I thought it might run the risk of preaching practical significance as a way of replacing statistical significance. Dr. Ellis does not go down that path at all, in fact quite the opposite. It is a very well explained approach to the importance of paying attention to both practical and statistical significance in the same research effort.” ~Amazon reviewer

“Too many stats texts focus on p values and alpha testing, versus computing and interpreting effect size. I’ve taught statistics and research design at Psychology Departments at various universities over the past 25+ years before retiring. If I still taught, I would definitely include this book, even at the undergraduate level, and refer to it at least when dealing with effect size.” ~Amazon reviewer

The three-book bundle comes in 2 formats: PDF and ePub. Get your copy now!