Researchers have highlighted for decades that sample size justification through power analysis is the exception rather than the rule. Even when authors do report a power analysis, there is often no justification for the smallest effect size of interest, or they do not provide enough information for the analysis to be reproducible. We argue one potential reason for these omissions is the lack of a truly accessible introduction.

Dr. James Bartlett, lecturer in psychology at the University of Glasgow, UK, together with Dr. Sarah Charles who completed her PhD at King’s College London, UK in the department of psychology, will introduce power analysis using the open-source software jamovi.

Structured around their recent tutorial article – Power to the People: A Beginner’s Tutorial to Power Analysis using jamovi –, they will outline the key concepts and provide a walkthrough of different types of power analysis using jamovi. They will discuss tricky decisions you will need to make, such as choosing an effect size and balancing your inferential goals with your resources. By the end of the webinar, you will be able to understand the fundamental concepts behind power analysis and extend them to more advanced statistical models.

Anyone is eligible to join this workshop, especially when new to power analysis in research. For example, students who are learning about research methods or researchers who want to use power analysis in their studies.

The desired outcome is that, by the end of the webinar, you will be able to:

  • Understand the fundamental concepts behind power analysis such as alpha and power.
  • Recognize useful types of power analysis such as a priori and sensitivity.
  • Justify the parameters you use in power analysis such as your smallest effect size of interest.
  • Use jamovi to apply and report a power analysis for two independent and two dependent samples.


  • 30 minutes: We will present an overview of the fundamental concepts behind power analysis and the decisions you must make.
  • 30 minutes: We will provide an interactive walkthrough using jamovi for different types of power analysis applied to two independent samples and two dependent samples.
  • 30 minutes: We will discuss how you can approach power analysis for more advanced statistical models and answer any questions about the webinar content.


  • Recommended: Download jamovi and install the jpower module (if you don’t know how to install a module in jamovi, check out this blog post by Dr. Matt Howard).
  • Optional: Read our preprint tutorial article: [“Power to the People: A Beginner’s Tutorial to Power Analysis using jamovi”].
  • Optional: Note down common ranges of effect sizes in your subject / area of research, so that we can discuss effect sizes from different disciplines and you can try them in the walkthrough.

The event will take place on February 17th, 2022, at 14:00 pm CET and will last approximately 90’. An invitation email, including the Zoom link, meeting ID, and password has been sent via the OSCR mailing list. If you are not part of the mailing list and you would like to join this workshop, please contact Eirini. If you are unable to attend in person, no need to worry. The event will be recorded and all members will be emailed with the link of the recording within a few days. You may submit questions regarding the speaker/ journal on this Google Doc.

Zoom Instructions

  • In case you have never used Zoom, go to the official website and follow the steps provided to install the app before the meeting. It will only take you a couple of minutes.
  • As a recommendation, use a computer instead of a cell phone to join the call. That is because the sound quality is often better on a computer and the zoom app on the phone is not user friendly.
  • Similarly, on the bottom side of your screen there is a chat icon. By clicking on it you open the chat where you can write any questions, answers, or comments.

Participation Instructions

  • Please follow these guidelines for safety and confidentiality:
  • Please arrive 5 minutes before the start of the event so that you can introduce yourself to the group and be present when we begin.
  • Mute your microphone unless you are invited to speak. Unmute when you are speaking and mute when you finish speaking. There is a microphone icon on the bottom side of the screen. By clicking on the icon, you mute and unmute.
  • Video is optional (in case of connection issues, you may be asked to turn it off)
  • We recommend using headphones to make sound quality better for you and others. Background noise and static can diminish the quality of the call for everyone.
  • Pay attention to the moderator (which will be Eirini).
  • If you have any questions:
    • Click on the Raise Hand button and the moderator will unmute you; or
    • Write down your question in the chat and the moderator will read it.

Please remember that attendees of every OSCR event (in person and/or online) are required to follow our Code of Conduct.

Hope to see many of you!

Take care,

James Bartlett, Sarah Charles, Eirini Botsari, and Antonio Schettino