Quantile-Quantile Plots (QQ plots), Clearly Explained!!!

Quantile-Quantile (QQ) plots are used to determine if data can be approximated by a statistical distribution. For example, you might collect some data and wonder if it is normally distributed. A QQ plot will help you answer that question. You can also use QQ plots to compare to different datasets that you collected to determine if their distributions are comparable. This video shows you how to do both things.

NOTE: The data in this video are measures of gene expression. If "gene expression" doesn't mean anything to you, just imagine that the data represents how tall a bunch of people are, or how much they weigh. Then consider the y-axis to be the height or weight of the people, and the x-axis just represents all of the data you collected on a single day. In this case, all of the data were collected on the same day, so they form a single column.

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Corrections:
4:35 The Uniform Distribution has one extra quantile
5:30 I should have said that Quartiles divide the data into 4 parts.

#statquest #quantile #qqplot

[maindepth]

that intro alone, made me forget my hate for statistics and instantly fall in love with it

[kittyxing]

Thanks much! This is the only video I found explained the details of generating QQ plot and also make the concept so clear and easy to understand!

[timonveurink]

Haven't seen the video yet, but that intro earned you a subscription

[robertopizziol]

I was waiting for the "BAAM" all video long, got just a couple of great "HOORAY!".

Thank you for the awesome channel Josh!

[alisalehi]

I really appreciate from your very easy way explanation.
I faced with so difficult and rough terminologies that I could not even understand the meaning of them.

[aashishshrivastav]

🤔🤔🤔🤔🤔 well I thought that q-q plot was difficult but thanks to you I got it now. thanks and keep it up!!!

[kevon]

Couldn’t have asked for more clear explanation, thanks!

[Clarint]

You had my like at the beginning with the jingle. Thanks for explaining this so well!!

[robertocannella]

Thanks for all the videos! Great music BTW. Also I'm looking forward to rockin' my new SQ hoodie!

[dominicj]

Can you do a video on normality tests like shapiro wilk and anderson darling? If not anytime soon, can you share link to some good materials?

[kusocm]

Best intro song, it can be used as a 'mnemonic' for what QQ plots are used for =)

[anaswahid]

Sir I have been facing problem in ggplot2 package in R programming now a days
Could you please help?

[pradiptithakur]

Awesome video. Explained so clearly. Really helped me a lot!

[josevaldes]

Triple BAMM! Serious man your channel is pure art. Thanks

[hebaebrahem]

Your videos are cool and concise, thank you .

[sirisudweeks]

very nicely explained. it was a tricky concept until this video! thanks!

[joerich]

is there a statistical test we can do to determine how far away the dots are allowed to deviate, rather than just eyeballing it? Or is eyeballing good enough? I.e. a stat test that could say 'the chance of these 2 distributions being the same is less than X%

[piotrszocik]

Great explanation, have a nice day :)

[iichnws]

It's so clear! Thanks a lot for your video.

[padraiggluck]

Really excellent presentation, Josh. ⭐️