Slides from my talk on how to do power analysis for longitudinal 2- and 3-level models.
Hereβs the slides from a talk I gave recently at Stockholm University: βPower Analysis for Longitudinal 2- and 3-Level Models: Challenges and Some Solutions Using the R Package powerlmmβ.
The slides gives several code examples for a lot of powerlmm
βs functionality, and explain some of the terms I use.
Written by Kristoffer Magnusson, a researcher in clinical psychology. You should follow him on Bluesky or on Twitter.
Published April 11, 2018 (View on GitHub)
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A huge thanks to the 175 supporters who've bought me a 422 coffees!
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I love your visualizations. Some of the best out there!!!
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I've been looking for applets that show this for YEARS, for demonstrations for classes. Thank you so much! Students do not need to tolarate my whiteboard scrawl now. I'm sure they'd appreciate you, too.l
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Thank you for putting this together! I am using these visuals and this information to teach my Advanced Quant class.
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Hi Krisoffer, these are great applets and I've examined many. I'm writing a chapter for the second edition of "Teaching statistics and quantitative methods in the 21st century" by Joe Rodgers (Routledge). My chapter is on the use of applets in teaching statistics. I could well be describing 5 of yours. Would you permit me to publish one or more screen shots of the output from one or more of your applets. I promise I will be saying very positive things about your applets. If you are inclined to respond, my email address if Chip.Reichardt@du.edu.
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Nice work! Saw some of your other publications and they are also really intriguing. Thanks so much!
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You finally helped me understand correlation! Many, many thanks... π
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Good stuff! It's been so helpful for teaching a Psych Stats class. Cheers!
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Excellent and informative visualizations!
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Always the clearest, loveliest simulations for complex concepts. Amazing resource for teaching intro stats!
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For a couple years now I've been wanting to create visualizations like these as a way to commit these foundational concepts to memory. But after finding your website I'm both relieved that I don't have to do that now and pissed off that I couldn't create anything half as beautiful and informative as you have done here. Wonderful job.
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You have an extremely useful site with very accessible content that I have been using to introduce colleagues and students to some of the core concepts of statistics. Keep up the good work, and thanks!
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Keep up the good work!
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I wish I could learn more from you about stats and math -- you use language in places that I do not understand. Cohen's D visualizations opened my understanding. Thank you
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Thank you, Kristoffer
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Great webpage, I use it to illustrate several issues when I have a lecture in research methods. Thanks, it is really helpful for the students:)
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Hard to overstate the importance of this work Kristoffer. Grateful for all you are doing.
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Some really useful simulations, great teaching resources.
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Thanks for fixing the bug yesterday!
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This is awesome! Thank you for creating these. Definitely using for my students, and me! :-)
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very useful for my students I guess
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Preparing my Master's student for final oral exam and stumbled on your site. We are discussing in lab meeting today. Coffee for everyone.
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What a great site
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Wonderful work!
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Terrific work. So very helpful. Thank you very much.
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I am so grateful for your page and can't thank you enough!Β Β
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Wonderful work, I use it every semester and it really helps the students (and me) understand things better. Keep going strong.
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Sal bought βββββ (5) coffees
Really super useful, especially for teaching. Thanks for this!
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Very helpful to helping teach teachers about the effects of the Good Behavior Game
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Amazing visualizations! Thank you!
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So good!
tchipman1@gsu.edu bought βββ (3) coffees
Hey, your stuff is cool - thanks for the visual
Hugo QuenΓ© bought βββ (3) coffees
Hi Kristoffer, Some time ago I've come up with a similar illustration about CIs as you have produced, and I'm now also referring to your work:<br>https://hugoquene.github.io/QMS-EN/ch-testing.html#sec:t-confidenceinterval-mean<br>With kind regards, Hugo QuenΓ©<br>(Utrecht University, Netherlands)
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Thanks so much for helping me understand these methods!
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Keep up the splendid work!
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Love this website; use it all the time in my teaching and research.
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Powerlmm was really helpful, and I appreciate your time in putting such an amazing resource together!
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This is very helpful, for my work and for teaching and supervising
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Regina bought βββ (3) coffees
Love your visualizations!
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Thanks. I really love the simplicity of your sliders. Thanks!!
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Thanks for making this Interpreting Correlations: Interactive Visualizations site - it's definitely a great help for this psych student! π
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brilliant simulations that can be effectively used in training
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Amazing illustrations, there is not enough coffee in the world for enthusiasts like you! Thanks!
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πWhat a great contribution - thanks Kristoffer!
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Wow - your website is fantastic, thank you for making it.
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mikhail.saltychev@gmail.com bought βββ (3) coffees
Thank you Kristoffer This is a nice site, which I have been used for a while. Best Prof. Mikhail Saltychev (Turku University, Finland)
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Thanks - this will help me to teach tomorrow!
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Keep the visualizations coming!
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Thank you so much for your work, Kristoffer. I use your visualizations to explain concepts to my tutoring students and they are a huge help.
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Thank you for making such useful and pretty tools. It not only helped me understand more about power, effect size, etc, but also made my quanti-method class more engaging and interesting. Thank you and wish you a great 2021!
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Used your vizualization in class today. Thanks!
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Enjoy.
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Thank you for using your stats and programming gifts in such a useful, generous manner. -Jess
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Thank you for building such excellent ways to convey difficult topics to students!
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Really wonderful visuals, and such a fantastic and effective teaching tool. So many thanks!
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Archived Comments (1)
Thanks for an excellent talk yesterday! Probably the one with the largest audience (at least the last couple of years). I have already had one person who could not attend asking for the slides of thanks for also sharing those!