Appendix A — Before you start

The primary purpose of this course is to help you to understand how to use statistics that will help with your research. The course will try to explain statistics using the same path through the topic that statistics students are educated along, but without the rigorous mathematical background necessary for those students. Instead this course will focus on making you aware of the major concepts and help you to be a better user of statistics in your research.

Statistics is a computationally heavy topic, so we’ll be making use of the R statistical programming environment to do that side of the work.

A.1 Running the code

All the code examples and exercises in this book run right here in your browser — when you see a code cell, just press Run and the result appears beneath it. You can edit the code and run it again to see what changes.

A.2 Knowledge prerequisites

There are no specific knowledge prerequisites for this book but it will help if you have heard of some common statistical tests, like t, ANOVA and regression. It’ll also be helpful for following some of the code examples if you are familiar with basic R use.

A.3 The itssl package

As you read along you’ll see functions with names like its_<something-something>_time(). These come from itssl, a package written solely to accompany this course, and it’s already loaded for you in the code cells. The main purpose of these functions is to make the course easier to follow and to stop us from getting bogged down in a lot of circumstantial code that isn’t directly related to our current point, which will usually be statistical rather than related to programming — so you’ll be able to get a lot out of this course even if you haven’t used much R before.

If you do have a desire to see the code inside the itssl functions it is available at https://github.com/danmaclean/itssl/tree/master/R.