Preface

This website contains tutorials and templates for statistical analysis in R markdown. It is primarily meant as reference material for the statistics course taught at the Institute of Biology Leiden, Leiden University.

This is not a general reference for how to do statistical analysis. That cannot be done concisely for a number of reasons:

  • The right analysis depends on the goal of the study. Is the study exploratory? Is there a predefined hypothesis to be tested? Is the main goal prediction? Is the main goal (causal) inference? Has the study been properly designed for this goal?
  • Phenomena that complicate typical analysis. Usually, a substantial part of analysis involves data cleaning, getting the data in tidy format, dealing with missing data, and identifying any number of other potentially complicating factors (censoring, zero-inflation, etc.).
  • Limitations of frequentist statistics.
  • Limitations of any supposedly exhaustive list of techniques. If your problem does not easily fall into one of the categories of analysis shown here, I recommend you consult with a statistician.

Finally, please note that this page is meant to show you how to do things, not how statistical methods work. For that, please refer to our free online material over here.

The tutorials website is a work in progress. Please check back later for updates.