Quantile Normalization, Clearly Explained!!!

Quantile Normalization lets us compare data that has all kinds of noise in it. It sounds fancy but is really super simple. Essentially you just sort each sample data from high to low. If your samples are rows, you then replace the values with the average of each row. BAM!

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[mzheng]

I searched for an hour to get a clear understanding of normalization and you explained it in 30 seconds. Thank you!

[tanishasharma]

Short, well-explained and so much better than the confusing webpages I was wasting my time on. Saw your video on quantiles and percentiles as well! Thank you so much for these videos, they help me both with my job and statistical knowledge!

[alirezaforoozani]

Oh how I wish you were my maths teacher, you make it seem so easy! I thank and salute you, sir!

[charliejin]

thanks! quite a simple and clear explanation! much much better than our lecturers

[RDFannin]

Good grief, this is good stuff! I wish there was something as clear for learning R code

[khaledgeba]

Thanks so much Josh! Nice Explanation, you made my day!!

[hieuthepunk]

This is the clearest answer i get about normalization. Thank you

[lunapeverell]

As always, this is the only way statistics comes easy and non unbearable to me. Thanks!

[blenderwang]

You did a great explanation, man! Thank you!

[shuaishigao]

Very helpful, that's exactly what I'm looking for! Thanks Joshua.

[afs]

my mum asked what am I watching when she heard the intro, didn't know how to say it's an educational video

[moomoocheng]

very great vedio, explained so clear that even I can understand，I am pretty new to bioinformatics, I am very confused about the relationship between quantile normalization and mas5 or rma normalization.

[veeranagoudayaligar]

It looked complicated, after watching your video, Umm, very simple. Thanks a lot.

[ai]

At 3:32, one thing I noticed is that the the red colored gene for samples 1 and 3 now have the exact same intensity values. In reality this is almost certainly not true. I notice this a lot when performing RMA for microarrays where Quantile normalization compresses smaller fold change differences. Is this just a caveat of the normalization method we just have to accept?

[zhaowu]

Thank you for this simple yet illustrative example pf quantile normalization. I would like to know what happened if we have missing values in some of the samples. Can we still do the quantile normalization ?

[糜家睿]

Hej, Joshua. Could you talk about the statistical methods that are used in single-cell RNA-seq, especially the normalization methods we used and the difference in analysis between bulk-RNA-seq and single-cell RNA-seq.

[saptashwachatterjee]

Please do a video on quantile regression

[etzhaim]

Thanks for this video. A question: Why perform quantile normalization instead of z-scores?

[muhammadabdullahnabeel]

@StatQuest Doesn't this normalization remove information? For example, in sample 2, the levels of expression are too high compared to sample 1 and we can't conserve this information.

[ranjeetkumar]

Hi, Nice Explanation. Could you talk on PCA vs Factor analysis difference?