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Stat 88 class - Shared screen with speaker view
Adam Lucas
21:31
HELLO!
lucyzhang
21:36
HIII
Kaci Gu
21:37
HI
Andrew Huang
21:37
hello
Jesse Thiara
21:38
hello!
lsandoe
21:40
hi
Rebecca Hu
21:41
Hello!
Dorkhan
21:44
hello!
Joshua
21:53
Hi!
lsandoe
22:05
yep
alvin
22:06
Hello There
Joshua
22:09
I miss you Prof. Lucas
lucyzhang
22:11
SAD
Andrew Huang
22:12
yea :/
iPhone (3)
22:14
Miss you too
chelsie
22:17
;((((
lucyzhang
22:21
How is final gonna be done? Do u know yet
Jesse Thiara
22:21
you're an oracle professor
Dorkhan
22:22
sad :(
Joshua
22:43
I don’t like working from home
Adam Lucas
24:27
OHs start today on Zoom. See piazza for details
Adam Lucas
25:53
can you guys hear me
Andrew Huang
25:58
no
Jesse Thiara
26:00
no
brendanco
26:00
no
Kaci Gu
26:01
no
lucyzhang
26:01
no
Joshua
26:04
nope
lucyzhang
26:10
U muted urself I think
Marisol Trejos
26:23
I can’t hear anything
Andrew Huang
26:32
that's good I think
Marisol Trejos
26:49
Yes
Rebecca Hu
26:49
yes
ashley minooka
26:50
ya
Andrew Huang
26:50
yes
ireneyoon
26:50
Yes
brendanco
26:50
yes
Joshua
26:51
yes
Kaci Gu
26:57
yes
Akshara Majjiga
26:57
yes
Andrew Huang
27:29
yes
Joshua
27:29
yep
Jesse Thiara
27:30
yes
brendanco
27:30
ye
Marisol Trejos
27:31
yes
Zachary Zhu
29:33
Yes
lsandoe
30:01
attempted
YeJin Ahn
30:25
working on b rn
Laura Nguyen
31:07
no
YeJin Ahn
31:08
no
ashley minooka
31:08
for b, got no
Joshua
31:09
no
Andrew Huang
31:10
no
iPhone (3)
31:13
No
Marisol Trejos
31:17
no
ashley minooka
31:23
1/3
iPhone (3)
31:23
1/3
lucyzhang
35:24
So the equal sign doesn’t really matter?
Rebecca Hu
36:12
Does k sigma = c?
Joshua
41:43
How did you get 7500?
Harry Xia
42:04
22500-15000
Joshua
42:11
Ah gotcha
Marisol Trejos
42:11
How did you get 5,000?
Zachary Zhu
42:30
Also, wouldn’t Markov give a better lower bound since the probability is lower?
lsandoe
42:38
how did you pick which one is better?
Zachary Zhu
42:39
Oh wait nvm
benskinner
42:40
Why is 4/9 the better lower bound?
Zachary Zhu
42:41
That’s 2/3
Zachary Zhu
42:45
Not 2/5
lsandoe
42:53
ohhhh
Zachary Zhu
42:55
My bad—misread the handwriting
Jessie
43:07
does chebyshev always give a better bound
chelsie
43:08
lol
amywang
43:09
What happened to the absolute value sign around Chebyshev’s? Wouldn’t we have to account for the left tail
Rebecca Hu
43:14
Is there another way to do the Chevyshev?
candice
44:48
Can I do (5000)^2/(22500-15000)^2 for chebyshev?
lucyzhang
44:57
Why did set 7500 equal to k(sigma)
lucyzhang
45:00
u*
candice
45:42
thanks
Harry Xia
45:43
22500 = 15000 + k(sigma)
amywang
45:44
So 4/9 actually represents the probability X is less than 1.5SD and more than 1.5SD from the mean but its just the best we can do to find more than 1.5SD?
carinamassana
45:52
How did 15000+ksigma get to 7500=ksigma
ireneyoon
48:01
^ 22500 = 15000 + 5000k and subtract 15000
brendanco
48:45
Will you be asking for both when testing us?
YeJin Ahn
49:04
I have a question
YT HaliFlame
51:03
How do I raise my hand
ireneyoon
51:29
5 minutes after reading the problem maybe
ashley minooka
53:22
did you mean 1/(k^2)= 1/2?
celine
53:50
^^^^^^
Andrew Huang
53:58
^^^
brendanco
54:21
We’re solving for k
candice
56:14
Can you explain what “p be the proportion of numbers over 5” means
Michelle Sun
57:20
no
Michelle Sun
57:28
oops sorry
Michelle Sun
57:35
accident
candice
57:55
Oh ok got it
Noah Wadhwani
59:14
Wouldn’t it just be > 5? Not >=
Michelle Sun
01:00:26
can we use the logic that because chebychev is for two tails, but because we are only using upper bound it means we have to use markov?
Michelle Sun
01:01:27
yes
Michelle Sun
01:01:32
thank you!
Andrew Huang
01:02:48
on the last question, if we're saying numbers over 4 and we use the p(x>=5) aren't we missing all the numbers between 4 and 5
Alfredo
01:03:10
^^ but I think we are working with discrete values
celine
01:03:14
cheating
YT HaliFlame
01:04:31
lmao
YeJin Ahn
01:06:32
can we solve it by rewriting it as P(|X-u|) >= 30)?
Michelle Sun
01:07:03
why can we take out the square?
candice
01:07:08
How do we know mu is 10?
candice
01:07:13
oh ** sigma
Michelle Sun
01:07:36
yes
candice
01:07:39
Never mind I figured it out
tianyuzhou
01:08:11
Is that 1 - P(|X-u|) >= 30)?
Alfredo
01:08:40
so squarerooting the probability doesn't affect the answer?
Michael Madden
01:09:26
no that is the opposite
Alfredo
01:10:03
but I didn't see 1-(1/9) being squarerooted
Michael navruzyan
01:10:11
why is var(24) = 0
Michael navruzyan
01:10:55
gotcha
Michael navruzyan
01:10:57
thanks
Noah Wadhwani
01:14:18
Where are the recordings of lecture posted?
Michael navruzyan
01:17:13
1
Kaci Gu
01:17:14
1
Sophie Liu
01:17:14
1
YeJin Ahn
01:17:16
1
YT HaliFlame
01:17:17
1
Rebecca Hu
01:17:17
1
Brian Sumali
01:17:57
Do we have to learn how to derive these?
Rebecca Hu
01:18:27
Are we allowed to use the other way for Chevyshev where we do sigma^2 / c^2
Andrew Huang
01:18:32
can you explain where the q comes from again
Brian Sumali
01:18:38
Got it awesome thanks prof
Zachary Zhu
01:18:38
Q = 1-p
Leanna Chraghchian
01:18:46
do you have any info about how our final/quizzes are going to take place??
Brian Sumali
01:18:49
There wouldn’t be any dinner parties soon...
Michael navruzyan
01:19:26
kind of confused on how you can't add those variances in the hours slept example. can't you add var(8) + var(16) = var(24), so 0 + 0 = 0?
Noah Wadhwani
01:20:59
You should just give everyone 100% instead of a final
YeJin Ahn
01:21:05
can you solve the example question part b when rewriting it as P(|X-u|) >= 30)?
Michael navruzyan
01:22:20
yeah makes sense thanks
Alfredo
01:30:12
could you explain the reason why the probability is the same when you take the square root of the probability?
Alfredo
01:30:40
professor?