Foreword

This book is designed to help people understand the statistical tests commonly taught in a Psychology undergraduate course by walking through the tests in a step-by-step process.

When we run analytical tests we often employ a statistical software to carry out the tests for us and our role, as researchers, is reduced to inputting the data in a correct format and interpreting the output. However, for us to understand and verify that the software is working correctly we must have some working knowledge of the test being used. For example, if a t-test comes back positive or negative, by understanding the processes involved in the calculation we can understand why that happens and what it means in terms of the research question we have set. Likewise, by understanding how degrees of freedom relate to different tests we can verify the output from the software, making sure that the values we get are appropriate. So whilst we, as researchers, will rarely have to run a full analysis by hand, and from memory, to fully understand the analyses that are the bases of the papers we write, it is important to know our way around those tests and how they work; it is unwise to just use an analytical software blindly without having some grasp of what it is doing and then using that output to make claims about human behavior.

We hope that this book helps in that understanding and in turn improves your research practice. If you have any suggestions for improvements to this book or would like to see a test added, please do let us know!