Data Analysis 6: Principal Component Analysis (PCA) - Computerphile

This series was made possible by sponsorship from by Google.

This video was filmed and edited by Sean Riley.

[skydrow]

Thank you Dr. Mike. I showed this to my neighbors and they told me it totally changed their life. My village also greatly appreciated PCA.

[AwesomeCrackDealer]

Holy shit this pca explanation was just what i needed all this time

[adamtarnawski]

Dr Mike provided the best explanation of PCA to non-experts which I have ever seen. I very enjoyable and insightful video overall.

[heyandy]

pretty dope. here I was laboring away in 223 dimensions. now I can put food on the table for my family with the time saved by removing 100 dimensions. thank u dr mike pound and computerphile

[mrcoomber]

He's such a great presenter. Thank you for such wonderful videos.

[manuarteteco]

Best PCA explanation I found so far, and I searched for days. Thanks man!

[nitika]

I finally get it!! It's people like you that keep me motivated for my work !

[kanewilliams]

Why even have lectures? This fella explained why we "maximize the variance" so clearly in the first 5 minutes.. Lecturers should just make us watch this video in class... great stuff!

[Zilfalon]

Thank you Dr. Pound, finally someone who can explain pca in easy words. Really helpful in my thesis - and by a strange accident I ended up writing both my thesis about pca. First time in my Bachelors I used it for data reduction, this time I use it to categorize data.

[harpercfc_]

I gotta say I enjoy this video so much and kinda started to under stand what PCA is and what it is used for. Totally a new and different angle to look at this concept. Thank you again Dr. Mike.

[OmarMohammed-fyhe]

Dude, you're better at explaining this than our uni professor :""D
please keep doing what you're doing.
Thank you.

[adityapatel]

this is brilliantly explained. one can only simplify if one truly understands it. thanks

[jsraadt]

I recommend doing a parallel analysis before extracting principal components. This will tell you how many PCs explain more variance than can be explained at random.

[brandonbracho]

best explanation for PCA I could find, thank you!

[Flourish]

This video was EXACTLY what I needed right now. Thank you so much!!!

[ErickMarkevich]

I really struggled to grasp the concept of PCA before, but thanks to your video it is now clear to me. Thank you

[HitAndMissLab]

Thank you for this brilliant video. In a less then a half an hour I developed intuition that it would take me a month to do from a book.

[gzuzchuy]

What a simple way to explain PCA! Thank you so much for the video.

[tellefsolberg]

Fricking loved that it was applied in R!

[tlniec]

Upon first hearing the phrase "principal component analysis", I thought it sounded very analogous to finding principal stress axes in a body under load. As Dr. Pound gave a more detailed explanation later, I realized that is exactly what it is - just expanded to take place in n-dimensional space instead of 3D space. May be a helpful way to visualize for any mechanical engineers out there.