Measures of Location & Spread 12 • Coding - the theory • Stats1 Ex2F • 🤖
ฝัง
- เผยแพร่เมื่อ 29 ก.ย. 2024
- The best way to find videos for other topics is to go to my channel's homepage, then scroll down to the relevant section.
There are playlists per chapter, with videos linked to individual exercises. Thanks for watching!
for 10:56 shouldn't the old s.d be 25 not 50?
Yes you are correct! Pinning this comment.
Explained TREMENDOUSLY.
THANK YOU SO MUCH!!!!
Wish I had you as a teacher 😭
hi there......isn't the last value of standard deviation should divid by 5 not 10?
You are correct! It should say 25 rather than 50. My mistake!
hes saving our a levels!! best a level youtuber online - better than TLmaths
Thank you! But TLMaths is a legend, he's so good!
i found stats and mechanics tough but after watching these videos now i find it quite easy thanks
Hi, shouldn't variance at 11:40 be 256 as the original one was 64?
Variance = S.D squared. If the SD is being multiplied by 2 (so from 8 -> 16). Then the Variance will be 8 x 2 squared, which is 8 x 4 or 32, as written!
@@cerende9773 But the original variance was= S.D squared= 8^2= 64, therefore the new variance being 4 times the old variance --> new variance= 64*4= 256
Hello Mr Bicen, thanks for this amazing video, was wondering whether at 11:40 the answer was 256 rather than 32?
I think I didn't phrase my question very clearly - I should have said that if the variance was 8, the new variance would be 32. You are correct that if the standard deviation was 8, then the new variance would indeed by 256!
@@BicenMaths thanks for getting back to me that’s now clear, however I still don’t get - if the variance was 8, then why would the new variance would 32? May you please explain this further, thank you.
@@BicenMaths hello sir, may you please get back to me whenever you can, thank you 😊🙏
Basically if we multiple the variable by something, then the variance is multiplied by that thing squared. I think I have confused things with saying stuff that wasn't in the table! Don't worry about it and don't over complicate @@jamie7707
I don't understand why in 7:26, whenever we multiply by a number (say y=3x) the standard deviation changes? For example If we tripled the heights of everyone, wouldn't the deviation / spread still be the same?
Let's think about the range instead of the standard deviation, as they both measure spread of data. If the shortest person was 100cm, and the tallest was 200cm, then the range is 200-100=100. If we tripled everyone's heights, the shortest is now 300cm, and the tallest is now 600cm. The range is now 600-300=300 which has also tripled! So range and standard deviation also get scaled.
However, we if we added 10 to everyone's heights, the shortest would be 110cm, and the tallest 210cm. The range is now 210-110=100 which is the same, so adding/subtracting makes no difference.
@BicenMaths really nice explanation. thank you!!
5:01