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Covariance vs Correlation with simple data | Covariance vs Correlation Coefficient 

Unfold Data Science
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Covariance vs Correlation with simple data | Covariance vs Correlation Coefficient
#CovarianceVSCorrelation #UnfoldDataScience
Hello ,
My name is Aman and I am a Data Scientist.
About this video:
In this video, In explain about covariance and correlation. This is an important statistics concept to know and hence I have explained the difference between correlation and covariance in this video through a simple data. Below topics are explained in this video:
1. Covariance vs Correlation with simple data
2. Covariance vs Correlation Coefficient
3. What is difference between correlation and covariance
4. Understanding Correlation vs Covariance
5. How is Covariance different from correlation
About Unfold Data science: This channel is to help people understand basics of data science through simple examples in easy way. Anybody without having prior knowledge of computer programming or statistics or machine learning and artificial intelligence can get an understanding of data science at high level through this channel. The videos uploaded will not be very technical in nature and hence it can be easily grasped by viewers from different background as well.
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21 июл 2024

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Комментарии : 186   
@saikiranreddymekala1346
@saikiranreddymekala1346 Год назад
In the formula of cov(x,y) the denominator is N-1 . Can you please correct this sir!
@UnfoldDataScience
@UnfoldDataScience Год назад
I will pin this on top of the video.
@pkavenger9990
@pkavenger9990 Год назад
actually if you are applying this formula on sample then its N-1 otherwise if you are applying on population then its N.
@vaibhavpandey7398
@vaibhavpandey7398 Год назад
@@pkavenger9990 thanks
@SomnathGupta-gu2rm
@SomnathGupta-gu2rm 8 месяцев назад
You are a Genius Sir. Thank You So Much for making these Concepts Simple and Lucid. May God Bless You 🙏🙏💐💐
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Access Hindi, English courses here- www.unfolddatascience.com/s/store Plz register on the website
@niii5715
@niii5715 Год назад
how calm u r while talking man ,excellent explaination! Hats off 🙇‍♂
@karthikaanilkumar
@karthikaanilkumar Год назад
IT'S REALLY AN EASY CLASS AND THE WAY OF YOUR PRESENTATION IS GREAT.
@prasadgpa6813
@prasadgpa6813 3 года назад
You nail it in every your videos . You sell the simplified knowledge . Keep it up and may God bless you.. Can't wait for more such videos :)
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks Prasad for motivation.
@user-pb6pt4rw1l
@user-pb6pt4rw1l Год назад
Amazing video! Such simple explanation, you earned a loyal subscriber today :)
@Nannyhere
@Nannyhere Месяц назад
Just watched it before exam and in one go ,i understood the concept ❤keep making such videos sir 🥰🥰
@kavyanagesh8304
@kavyanagesh8304 Год назад
You are the best teacher! Got goosebumps while listening to your lecture. Thank you so much!
@UnfoldDataScience
@UnfoldDataScience Год назад
Thanks Kavya. Pls share with friends as well. Keep learning
@gaytriray7019
@gaytriray7019 3 года назад
You are amazing at what you do! Your passion and dedication is beyond words! Thankyou so much sir.
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks Gayatri for motivating me through your comment.
@ayushagarwal7284
@ayushagarwal7284 Год назад
Awesome video sir...Keep shining😀
@best_movies3736
@best_movies3736 2 года назад
You are simply the best! The MasterBlaster in Data Science
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Thanks alot Thurab. Continue watching
@sexycurse
@sexycurse 2 года назад
Amazing explanation brother..Good Job..👍👍👍
@ketakishitut2713
@ketakishitut2713 Год назад
Very well explained, thanks
@siddheshbhalerao3013
@siddheshbhalerao3013 Год назад
Thank you sir for clean explanation.
@omdodmani3205
@omdodmani3205 10 месяцев назад
Loved it 😊! you made it very easy to understand thanks !
@andresgrtz
@andresgrtz Год назад
Thank you! Great teacher!
@yoharihernandez
@yoharihernandez 2 года назад
Thank you so much! it was hard for me to understand this concept until I found this video. Please keep doing more videos!
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Thank you Yohari! Will do!
@k.vvishwanathan7341
@k.vvishwanathan7341 Год назад
Pls clear my doubt.covariance is the way two variables move. Whether positive or negative but what is correlation of those Variables. How much have they moved ? Like if covariance is nearby to -1 then the two variables move in the opposite direction?
@animetalks2129
@animetalks2129 Год назад
sir can you suggest a tabelau course for me ? i am confused where to learn from ?.
@user-qd2dp8ru9w
@user-qd2dp8ru9w Месяц назад
V good, thanks
@financenanchahal8801
@financenanchahal8801 2 года назад
Amazing explanation sir.....
@soheilaahmadi4807
@soheilaahmadi4807 2 года назад
Was amazing. Happy to find your tutorials on RU-vid.
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Thanks Soheila.
@_itachi7904
@_itachi7904 3 года назад
after so much of head banging finally I understood covariance & correlation....thank you so much...
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks a lot.
@anaskhan4841
@anaskhan4841 2 года назад
Thank you Aman❤
@sudhakarvasa2688
@sudhakarvasa2688 Год назад
When Yi value is changed from 32 to 48 mean of y will also change
@jigyasasoni1812
@jigyasasoni1812 Год назад
with in a 1:30 sec.... i can say, you are the best teacher.
@UnfoldDataScience
@UnfoldDataScience Год назад
Thank you Jigyasa. Your comments mean a lot to me
@pokejishnu
@pokejishnu 3 года назад
Amazing explanation Aman bhai ... Made it sound so simple. Thanks this helps.
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks Jishnu da.
@sameerpandey5561
@sameerpandey5561 3 года назад
Beautifully explained!!...Thanks for such content
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks Sameer.
@vidyaanvekar
@vidyaanvekar 2 года назад
Thanks for the wonderful explanation. You made my understanding very concrete.
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Welcome Vidya.
@bipintiwari8751
@bipintiwari8751 2 года назад
why exponential is calculated can you please explain that as well.
@bayz4918
@bayz4918 4 месяца назад
it is good keep it up
@champabanerjee1208
@champabanerjee1208 2 года назад
You made it so clear....thank you so much 🙏❤️
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Welcome
@shabiyaahlam3217
@shabiyaahlam3217 2 года назад
Helpd me a lot!
@omkarnarayankar5275
@omkarnarayankar5275 2 года назад
Best explanation
@humanafees8059
@humanafees8059 3 года назад
Thank u so much I m.doing msc buisness analytics from Scotland seriously for every questions that hit me I come to ur channel I m.ur new subscriber God bless you
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks for your words Huma.
@ajaykumarsahoo1404
@ajaykumarsahoo1404 3 года назад
Hey I have a doubt. When you change the value of a y variable from 32 to 48 .. Will it mean remain same that means mean will not change? If change then how can you subtract the previous mean from the new value of y?
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Let me check once.
@simplicityandchaos976
@simplicityandchaos976 2 года назад
Changing the value of Y variable from 32 to 48 changes overall mean of Y and hence it cannot be subtracted from the previous.
@parol3271
@parol3271 3 года назад
Thanks a lot . A very detailed explanation . Great yaar🙏👍👌
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Glad you liked it.
@ragess4rari100
@ragess4rari100 2 года назад
Thank you sir. You're a great teacher.
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Welcome.
@onuragmaji
@onuragmaji 2 года назад
Good work bro ur teaching style is very cool, keep posting such great content
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Thanks Anurag.
@haidiazaman3326
@haidiazaman3326 3 года назад
fantastic channel, def deserves more views
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks Haidi.
@gangavijayan8906
@gangavijayan8906 9 месяцев назад
Why covariance is divided by standard deviation?
@rishabhsheoran6959
@rishabhsheoran6959 2 года назад
Kaafi achhcha samjhaya bhai! Good work!
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Thanks Rishabh, thoda share kar dijie apne groups me :)
@sandipansarkar9211
@sandipansarkar9211 2 года назад
finished watching
@vinayverma9121
@vinayverma9121 2 года назад
You are amazing buddy you explained it so simply
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Thanks Vinay for your positive feedback. Please share with others as well who could be benefited from such content.
@sanjeevkmr5749
@sanjeevkmr5749 3 года назад
Amazing explanation. Please keep doing the great work. This channel deserves more!!! I have heard that before training a ML model, it is advised to remove highly correlated features, Can you explain why?
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Hi Sanjeev, I created a detailed video for this question, Watch it on my channel today 7pm IST. :)
@sanjeevkmr5749
@sanjeevkmr5749 3 года назад
@@UnfoldDataScience Thanks a lot!
@karthickk6587
@karthickk6587 2 года назад
Amazing Aman
@UnfoldDataScience
@UnfoldDataScience 2 года назад
THanks Karthick
@sadhnarai8757
@sadhnarai8757 3 года назад
Much needed,thanks :)
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Welcome :)
@tusharbedse9523
@tusharbedse9523 2 года назад
Nicely explained again Aman!
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Glad you liked it Tushar.
@RamanKumar-ss2ro
@RamanKumar-ss2ro 3 года назад
Thanks a lot for this topic.
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Welcome again :)
@usmanzahid3711
@usmanzahid3711 Год назад
What exactly co variance is
@m12gaming81
@m12gaming81 6 месяцев назад
sir ur doing great work luv u
@UnfoldDataScience
@UnfoldDataScience 6 месяцев назад
So nice of you
@soumyaranjansethi1790
@soumyaranjansethi1790 3 года назад
Amazing sir thank you
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Most welcome Soumya.
@adityapatki151
@adityapatki151 3 года назад
Hey I am data scientist too and really like your content . Can you make a video about how to select (statistically) control group size for marketing campaign?
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks Aditya. Let me think through it. Thanks for asking.
@launchdome3219
@launchdome3219 3 года назад
very helpful...good job
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks a lot.
@Storiesbymanas
@Storiesbymanas 3 года назад
nicely explained. thank you!
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Glad it was helpful!
@jay_with_the_real6381
@jay_with_the_real6381 3 года назад
Excellent thanks!
@UnfoldDataScience
@UnfoldDataScience 2 года назад
You're welcome!
@nagamuthu4382
@nagamuthu4382 3 года назад
i would like to compare the advances level in banks. is covariance useful to compare the gross advances of public and private sector banks for 10 years.
@UnfoldDataScience
@UnfoldDataScience 3 года назад
May be you can use advance technique. Its a simple technique.
@RishabhRishab
@RishabhRishab 3 года назад
What purpose Covariance value / number is serving ? If I say sign of Covariance tells nature of relationship and Covariance value tells strength of relationship and there is no need of correlation .... how is this statement wrong ?
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Good question, however covariance is base of correlation hence that concept came first.
@kanamarlapudinaresh9934
@kanamarlapudinaresh9934 3 года назад
Thanks much. In last formula, you mentioned (standard deviation of x) ( standard deviation of y ) in denominator. How we will calculate and can you explain.
@UnfoldDataScience
@UnfoldDataScience 2 года назад
watch variance and sd video
@emineakpnar6215
@emineakpnar6215 3 года назад
it helped me a lot, thank you🙌
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Glad it helped!
@jrsolomon5960
@jrsolomon5960 3 года назад
Thanks...this is very clear.
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Glad it was helpful!
@SumitSinghXd
@SumitSinghXd 3 года назад
Great work .. These two terms were alien for me and the online website have complicated it more. Thanks to you I have understood it completely. just a single doubt , I have seen in many websites the denominator for variance is taken N-1 and in your video its N . which one should I go for
@tgbyhn841997
@tgbyhn841997 2 года назад
For population data N is taken and for sample data N-1
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Glad it helped!
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Thanks Rahul
@jananiravinag
@jananiravinag 3 года назад
Great resource!
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks a lot.
@yogitabasnal
@yogitabasnal 2 года назад
Great explanation
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Glad it was helpful!
@kiranpol1601
@kiranpol1601 3 года назад
wow... What a explanation
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks Kiran.
@afn8370
@afn8370 Год назад
thanksss
@binitkumarsingh8409
@binitkumarsingh8409 2 года назад
how to find standard deviation of x and y..basically that denominator
@UnfoldDataScience
@UnfoldDataScience 2 года назад
We no need to compute from scratch, tool will help to do so
@salmanjaved2816
@salmanjaved2816 3 года назад
Thanks bro 👍
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Welcome Salman.
@balajinatarajan1051
@balajinatarajan1051 2 года назад
Excellent video
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Thanks Bala.
@sudheerrao9820
@sudheerrao9820 3 года назад
Thank you for the video Aman...if four features are positive correlated and four features are negative correlated out of 10 features in dataset...what should we do...I mean which are needs to be dropped and why?
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Good question Sudheer. To keep it short, choose the variables which are highest corelated with your target variable(Either positive or negative).
@learningsinlife
@learningsinlife 2 года назад
mean will also change if 48 is made new observation
@megabuzu2726
@megabuzu2726 3 года назад
Perfect explanation
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks Matthew.
@vcalls9146
@vcalls9146 3 года назад
How the new data is handled after the model is moved to production. Example: During model development the categorical data is converted to 1 and 0 using one hot encoding... When the new data is applied in production how the categorical data or text data is processed..
@UnfoldDataScience
@UnfoldDataScience 2 года назад
good question, u encode again and then predict.
@chikoo8486
@chikoo8486 3 года назад
The unit you are talking about in covariance is +ve and -ve ??
@UnfoldDataScience
@UnfoldDataScience 3 года назад
ya.
@lakshaykhandelwal4284
@lakshaykhandelwal4284 2 года назад
very well explained.. 👍
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Thanks Lakshay.
@madhurakhaire6583
@madhurakhaire6583 2 года назад
amazing explination
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Thanks Madhu.
@suhatharsanyoganathapillai2203
@suhatharsanyoganathapillai2203 2 года назад
Thank you
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Welcome.
@deepseaoflove3683
@deepseaoflove3683 3 года назад
Sir.. Divide by N Or (n-1) for finding convariance? In some lectures it is showing as by ( n-1)
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Does not matter if your sample size is large. See these answers: math.stackexchange.com/questions/2936143/do-i-use-n-or-n-1-as-the-denominator-for-covariance
@johnsubhash
@johnsubhash 3 года назад
@@UnfoldDataScience then, will it matter if it’s the case of small data set..? What should we take then.??
@mosama22
@mosama22 2 года назад
Thank you Amen :-) :-)
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Welcome
@udayteja6595
@udayteja6595 Год назад
sir, when you have changed 32 as 48 then the mean also should change . So, it will effect all the variances in numerator , not only the last one.
@tanmaypadhiar3529
@tanmaypadhiar3529 Месяц назад
yes same doubt
@rediscovermath
@rediscovermath 25 дней назад
When you changed 32 to 48, mean will also change.
@leilyb5224
@leilyb5224 2 года назад
Perfect 👍👍👍👍
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Thank you
@shubhamkumarjain1329
@shubhamkumarjain1329 3 года назад
Thank you so much... It helped a lot... But i want to know why it ranges between 1 and - 1 and not above that...
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Welcome Shubham, its because of internal mathematical formula.
@priyamkataria573
@priyamkataria573 2 года назад
Great content 🔥🔥
@UnfoldDataScience
@UnfoldDataScience 2 года назад
Appreciate it Priyam
@sandipansarkar9211
@sandipansarkar9211 3 года назад
great explanation
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Glad you liked it
@arihantchoudhary
@arihantchoudhary 2 года назад
❤❤❤
@D.H.Bangalore
@D.H.Bangalore 2 года назад
Looks like while increasing the value of y you forgot to increase the mean of y
@rohitbhosale4614
@rohitbhosale4614 3 года назад
You are a champ!
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks Rohit.
@Manya2017
@Manya2017 Год назад
Can you share the link of the data science group so that I can also join
@UnfoldDataScience
@UnfoldDataScience Год назад
unfold_data_science on instagram
@shoooooooooorts8002
@shoooooooooorts8002 2 года назад
Please make video on statistics for data science A-Z
@UnfoldDataScience
@UnfoldDataScience 2 года назад
ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-iZ2r7aIwMbc.html
@saurabsen3686
@saurabsen3686 3 года назад
Great presentation that is simple and to the point. However could not fully grasp when calculating correlation, dividing cov(x,y) by sd x multiplied by sd y yields a value between -1 and 1. Why so? Kindly revert.
@UnfoldDataScience
@UnfoldDataScience 2 года назад
The explanation will be little more mathematical, please see the discussion here Saurabh: math.stackexchange.com/questions/564751/how-can-i-simply-prove-that-the-pearson-correlation-coefficient-is-between-1-an
@humanafees8059
@humanafees8059 3 года назад
One suggestion can u please make a video for detailed probability for beginners please it a request
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks for suggesting, noted.
@ashokmeena9631
@ashokmeena9631 3 года назад
Sir what about virtual Interview
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Fill the form in the previous video. I will. Share invite.
@dr.sagarfirke2687
@dr.sagarfirke2687 3 года назад
Eexcelent
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks Sagar.
@anilkumarsharma8901
@anilkumarsharma8901 Год назад
Super computer ki power windows interface main karwa do phir Duniya following karegi Vedic math par reserch karwavo
@anilkumarsharma8901
@anilkumarsharma8901 Год назад
More computer power means more success
@vaibhavpandey7398
@vaibhavpandey7398 Год назад
I want to ask, ye t shirt sale pe ayi thi.. Wahi se li thi na 🤣🤣🤣🤣 joking. Liked ur video
@UnfoldDataScience
@UnfoldDataScience Год назад
Gift mila tha , dene wale se puchna padega :D
@sanyamsingh4907
@sanyamsingh4907 3 года назад
kids learn from udemy legends learn from unfold data science
@UnfoldDataScience
@UnfoldDataScience 3 года назад
Thanks Sanyam. your words are always motivating. :)
@khanraiyan123
@khanraiyan123 2 года назад
denominator should be N-1
@UnfoldDataScience
@UnfoldDataScience Год назад
Comment pinned for this
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