Interpreting Confidence Intervals – new d3.js visualization

Understanding confidence intervals – visualization. By Kristoffer Magnusson

I just published a new interactive visualization in my series of basic statistical concepts and techniques. This time I have tried to explain confidence intervals for means. This visualization shows a simulation of repeated sampling from a normal distribution with mean zero and a standard deviation of two. I also show the sampling distribution of the width of CIs, which follow scaled chi-distribution. You can change the confidence level and sample size to see how the CIs change.

Check out it here: rpsychologist.com/d3/CI/


Written by Kristoffer Magnusson, a researcher in clinical psychology. You should follow him on Twitter and come hang out on the open science discord Git Gud Science.


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Published November 28, 2014 (View on GitHub)

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A huge thanks to the 100 supporters who've bought me a 225 coffees!

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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

@LinneaGandhi bought ☕☕☕☕☕ (5) coffees

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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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!  

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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 ☕☕☕☕☕ (5) coffees

Really super useful, especially for teaching. Thanks for this!

dde@paxis.org bought ☕☕☕☕☕ (5) coffees

Very helpful to helping teach teachers about the effects of the Good Behavior Game

@akreutzer82 bought ☕☕☕☕☕ (5) coffees

Amazing visualizations! Thank you!

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So good!

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Amazing illustrations, there is not enough coffee in the world for enthusiasts like you! Thanks!

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🌟What a great contribution - thanks Kristoffer!

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Wow - your website is fantastic, thank you for making it.

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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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Keep up the nice work, thank you!

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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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My students love these visualizations and so do I! Thanks for helping me make stats more intuitive.

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For a high school teacher of psychology, I would be lost without your visualizations. The ability to interact and manipulate allows students to get it in a very sticky manner. Thank you!!!

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You Cohen's d post really helped me explaining the interpretation to people who don't know stats! Thank you!

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Enjoy.

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Teaching stats to civil engineer undergrads (first time teaching for me, first time for most of them too) and grasping for some good explanations of hypothesis testing, power, and CI's. Love these interactive graphics!

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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! Such a great resource for teaching these concepts, especially CI, Power, correlation.

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Fantastic work with the visualizations!

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Your work is amazing! I use your visualizations often in my teaching. Thank you. 

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this is a superb, intuitive teaching tool!

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Thank you so much for these amazing visualizations. They're a great teaching tool and the allow me to show students things that it would take me weeks or months to program myself.

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Thank you for sharing your visualization skills with the rest of us! I use them frequently when teaching intro stats. 

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Thanks for your work.

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Great work!

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Angela bought ☕ (1) coffee

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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I really like your work.

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You're awesome. I have students in my intro stats class say, "I get it now," after using your tool. Thanks for making my job easier.

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Incredibly useful tool!

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Hi Kristoffer, many thanks for making all this great stuff available to the community!

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Really helpful visualisations, thanks!

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Thanks so much for creating this! Really helpful for being able to explain effect size to a clinician I'm doing an analysis for. 

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Thank you so much for creating these tools! As we face the challenge of teaching statistical concepts online, this is an invaluable resource.

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Fantastic resource. I think you would be well served to have one page indexing all your visualizations, that would make it more accessible for sharing as a common resource.

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Fantastic Visualizations! Amazing way to to demonstrate how n/power/beta/alpha/effect size are all interrelated - especially for visual learners! Thank you for creating this?

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Incredible visualizations and the best power analysis software on R.

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Great website!

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Thank you for this work!!

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Nice explanation and visual guide of Cohen's d

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thank you

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Archived Comments (1)

A
Aurelie B 2018-02-12

Thank you very much for this visualization! Very helpful in understanding the misconception that accompanies confidence interval. Is it possible for you to provide additional commentary/explanation on what is going on in the visualization? I think this would definitely be very helpful for questions like these: https://www.quora.com/Why-d...