Why Open Access Books?

Accessibility and inclusion in Bayes Rules! book: Part I.

Bayes Rules! book
Bayesian education

July 24, 2020

Edit: most of this post’s content is now provided as a preprint: Framework for Accessible and Inclusive Teaching Materials for Statistics and Data Science Courses


I am writing an undergraduate Bayesian statistics book with Alicia A. Johnson and Miles Ott called Bayes Rules! An Introduction to Bayesian Modeling with R.

One of my favorite statisticians Emma Benn asked us a question about this book on Twitter.

The answer to Emma’s question is rather long so I thought I would post a series of blog posts to answer her.

First of all, why we are even writing this book? Our initial intent in writing this book is like many other professors’ who write their own textbook. We are writing the textbook that we would like to see in the world and use in the classroom. We all teach Bayesian statistics at the undergraduate level and struggle to find any books on Bayesian statistics appropriate at this level.

Our main goal is making Bayesian statistics accessible and inclusive to our readers. Of course a big portion of what we mean accessible is making statistics understandable. So we spend a lot of time discussing on how to write on probability, modeling, using R to model. In these blog posts I will not talk about statistical content, however, I will talk about what other things we are consider to write an accessible and inclusive book over three separate posts:

  1. Why Open Access Books?
  2. Who is in the Bayes Rules! Book?
  3. Considering Visual Challenges and Impairments

I should also note that this is my perception of our work. It is possible that my coauthors Alicia and Miles may disagree with some of this or they may express things slightly differently.

Why Open Access Books?

One thing that we all agreed on was that the book will be open access. The book will be published as a hard copy but I will explain why having an open access version is so important to me.

A personal story first. I came to the United States for college and like many immigrants, I do have a “I had X amount of dollars” story. The cost of textbooks in my first semester for four courses exceeded the amount of money in my pocket. I actually just checked the price of my calculus book The Language of Change is listed at $280.951 on Amazon. I was able to buy it back then only because my college decided to provide me full textbook support for all my courses throughout my undergraduate education.

Based on a survey2 conducted in 2018 at University of California Irvine, where I teach, 27% of the students have been identified with very low food security and 21% with low food security. When my students are not able to afford food security, in good conscience, I cannot see myself writing a book that my students would most likely will not be able to afford and ask them to pay for my own book when I teach the course. Also, note that these students are the ones teaching me how to be a better teacher and how to be a better writer. They make mistakes on my quizzes and exams that makes me reword examples and exercises. Their learning experience is a constant feedback on the book that no reviewer can provide.

Consider the cost of a textbook that costs $100. At the introductory level we have some courses (not Bayesian) that have 220 students. If all students were to buy the textbook that would be $22000 textbook cost per course. Consider how many times a course gets taught over and over again. I cannot say more on this.

This book is not just about me or students at my institution, textbooks are unaffordable for many. Just look at this survey result:

“Today, a survey released by the U.S. PIRG Education Fund shows that 65% of student consumers have opted out of buying a college textbook due to its high price, and of those students, 94% say they suffer academically”3.

It is also not only about students or those in the United States. I believe that there are many people from around the world who can benefit from this book. Consider this blog as an example. I have had it for only 11 days and it has been visited by people from 52 countries. Putting unaffordability of textbooks aside, I am not even sure if a physical copy of the book would even make it to so many countries.

In short, the book will be open access and there are many reasons for it. I am so glad Alicia and Miles agree on having an open access book as well.

Note: Open access statistics book initiative OpenIntro maintains a list of open access textbooks and I keep a list of open access resources for learning R at learnR4free.com. The site will soon have a list of resources in Spanish which will be compiled by Yanina Bellini Saibene. If you are currently looking for a Bayesian statistics book, Jim Albert and Monika Hu has Probability and Bayesian Modeling book.

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  1. If I remember correctly it was around $150 about 15 years ago↩︎

  2. https://www.universityofcalifornia.edu/infocenter/ucues-data-tables-2018↩︎

  3. https://uspirg.org/news/usp/survey-shows-students-opting-out-buying-high-cost-textbooks h/t David Diez of OpenIntro↩︎