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CS109 Lecture - Shared screen with speaker view
Mike Wu
00:36
here
Sarah McCarthy (she/her)
06:54
Happy Wednesday!
Asmaa Sultan
06:56
hii
Joseph Moser (He/Him)
06:58
hi!!
Sarah McCarthy (she/her)
06:59
Hi!
Neha Vinjapuri
07:00
hello!
Pete R
07:00
hi
abel john
07:01
hello
Anthony Qin
07:02
hiii
Calvin Laughlin
07:02
Hello!!
eli wald
07:03
hi!
Gashon Hussein
07:03
hi!
shan reddy
07:03
Hi!
yash patil
07:03
Hiii!!!!!!!
malek hodroj
07:03
hi
Alberto Mancarella
07:03
Hi!!!
Matt Wolff
07:03
hey!
Keely Podosin
07:03
hi!!
monica hicks
07:06
Hi!
Sarah McCarthy (she/her)
09:44
I really like these lecture problems in the app!
Asmaa Sultan
09:49
I find the lecture problems super usefull!!
Asmaa Sultan
11:14
Are we gonna learn about things like p value, chi square etc
Kunal
12:24
So cool
Mike Wu
13:51
We will be learning about a lot of different distributions. I don’t think we will be covering hypotheses tests but this class should set you up well to learn those concepts.
Kevin Mayer
16:25
Is it always possible to construct a sample space with equally likely outcomes? Or are there cases where it does not work?
Mike Wu
18:02
I usually think of the sample space as a set. So there is no sense of likelihood for sample space. The sample space just denotes the possible outcomes. Think of it as like the domain of a function.
monica hicks
19:33
P(efG)
yash patil
19:37
P(EFG)
Tenzin Chonzom
19:38
-P(EFG)
Asmaa Sultan
19:38
e+f+g
Olivia Bruvik
19:38
P(EFG)
Sarah McCarthy (she/her)
19:39
P(EFG)
Gabe Seir
19:39
P(EFG)
Keely Podosin
19:39
e and f and g
Jacob
19:39
P(E&F&G)
Tamilore (Ta-me-lo-reh)
19:40
Prob of all three happening
Caroline Graham
19:41
+ P(EFG)
Brian Xu
19:41
P(EFG)
Anna Edmonds
19:41
P(EFG)
Layton Rosenfeld
19:42
P(EFG)
Juben Rana (he/him)
19:44
Probability of all of them
Shubh Khanna
19:46
+ P (E and F and G)
Shubh Khanna
20:34
why do we add the triplet?
yash patil
23:38
The quadruple ANDs or ORs?
Shubh Khanna
23:40
why does this rule work?
Mike Wu
25:01
I think intuitively, the triplet example with the shaded Venn diagram is a good one. If we just add everything, we overcount a few events.
Shubh Khanna
40:51
do these have to be pair-wise independent in order for this formula to work?
Mike Wu
42:43
Yes I believe so
wesley larlarb
47:07
If you only roll two dice, is it by definition true that you can three events relating to those dice can never be independent
wesley larlarb
47:13
Since there were only two events
wesley larlarb
47:27
*that you can never have
Mike Wu
51:27
What is the third event in this scenario? If it is a function of the first two events, then yes!
Alex Waitz
53:38
1 - p1*p2*…*pn
Asmaa Sultan
53:52
Take five should be playing in the background of exams
Chris Piech
54:02
Yes! Agreed
wesley larlarb
54:08
The three events could be any definable events relating exclusively to the numerical outcomes of the dice… for example D1=7, or D2!=8, or D1 + D2 = 12 etc. What I’m suggesting is that since the system is determined initially by two variable events, it’s impossible to define 3 events in the outcome space which are independent from each other.
Chris Piech
54:14
Someone played it in the market on Sunday — and I almost started doing math
wesley larlarb
54:45
I don’t know if this makes sense it’s just a thought I had.
aadi nashikkar
56:12
1 - (p1*p2*…pn)
Michael Nath
56:46
1 - probably of all them failing?
calvin sokk
58:07
That symbol is like sigma but for multiplication?
Mike Wu
01:00:24
Yes like big sigma but for mtuliplication
Gabe Seir
01:02:01
0.8^10
Jonatan Pérez (he/him)
01:02:10
.8 ^ 10
Alex Waitz
01:02:13
0.5^10
Gashon Hussein
01:02:15
1/2^10
Keely Podosin
01:02:35
totally fine if you want camera off (cause zoom is hard haha) but not sure if you just forgot to turn it on?
Jonatan Pérez (he/him)
01:02:45
(1-.8)^10
Gashon Hussein
01:02:49
.8^10
Chris Cooper
01:02:51
0.2^10
Olivia Bruvik
01:02:54
(0.2)^10
Keely Podosin
01:02:55
hi!!
eli wald
01:03:01
.2^10
Chris Cooper
01:03:07
0.4^10
Calvin Laughlin
01:03:07
1 - .8^10?
Matt Wolff
01:03:11
0.2^10
Tenzin Chonzom
01:03:12
(.2)^10
Josue Contreras (he/him)
01:03:12
0.8^10?
Alex Waitz
01:03:14
0.2^10
avi udash
01:03:17
.2^10
eleanor sigrest
01:03:17
0.2^10
Sarah McCarthy (she/her)
01:03:20
(0.2)^10
Matt Wolff
01:04:18
(0.8^4)(0.2^0.6)
malek hodroj
01:04:28
0.8^4 * 0.2^6
Sarah McCarthy (she/her)
01:04:41
(p)^k * (1 - p)^(n - k)
Fletcher Newell
01:04:41
p^4 * (1-p)^6
Gabe Seir
01:04:41
p^k * (1-p)^(n-k)
Matt Wolff
01:04:42
(p^4)((1-p)^6)
Neha Vinjapuri
01:04:42
p^4 * (1-p)^6
avi udash
01:04:46
(p^k)((1-p)^n-k)
Chris Cooper
01:04:55
p^4 * (p-1)^6
Layton Rosenfeld
01:04:57
(p)^k * (1-p)^(n-k)
eleanor sigrest
01:05:08
p^n * (1-p)^n-k
Olivia Bruvik
01:05:21
p^k * (1-p)^(n-k)
Linda Tong
01:06:32
Multiply by 10 c 4?
Chris Cooper
01:06:34
210
Michael Nath
01:06:35
10C4
Chris Cooper
01:07:22
5/210
Steven Songqi Pu
01:07:27
Combinations instead of permutations?
Chris Cooper
01:07:52
1/210
patricia strutz
01:08:12
1/210
Jacob
01:08:20
p^4(1-p)^6
Gabe Seir
01:08:25
1/10!
haven whitney
01:08:28
The same as the first one no? Bc each flip is independent?
eli wald
01:08:29
1 in 2^10?
Matt Wolff
01:08:36
(p^4)((1-p)^6)
Chris Cooper
01:08:38
1/210+
Jonatan Pérez (he/him)
01:08:39
p^k * (1-p)^n-k
aadi nashikkar
01:08:44
1/2^10
Sarah McCarthy (she/her)
01:08:46
(P)^k * (1 - p)^(n - k)??
Viraj Mehta
01:08:48
p^k * (1-p)^1-k
Olivia Bruvik
01:08:51
1 / n choose n
Anthony Qin
01:08:53
p^k(1-p)^(n-k)
Michael Zhu (he/him)
01:08:53
(p)^4(1-p)^6
malek hodroj
01:09:00
0.8^4 * 0.2^6
Proud Mpala
01:09:25
P(4H) * (1/10C4)
Asmaa Sultan
01:13:12
a
monica hicks
01:13:20
A
eli wald
01:13:22
it’s both!
Anicet Dushime Wa Mungu
01:13:23
B
patricia strutz
01:13:25
b
Jonatan Pérez (he/him)
01:13:27
a?
Jeffery Shen
01:13:29
a
Sarah McCarthy (she/her)
01:13:30
Def a but maybe both?
patricia strutz
01:13:32
Wait a
Fletcher Newell
01:13:34
Both?
Alex Waitz
01:13:36
a
Aditya Tadimeti
01:13:36
both?
wesley larlarb
01:13:37
Both
Michael Zhu (he/him)
01:13:37
a
Riley Carlson
01:13:38
Both?
Alberto Mancarella
01:13:39
A
Jacob
01:13:39
Both
patricia strutz
01:13:41
Wait both
Shubh Khanna
01:13:42
both!
Gashon Hussein
01:13:46
b
Asmaa Sultan
01:13:46
B would be blue in the middle
Matt Wolff
01:13:47
a
Michael Souliman
01:13:47
A?
Chris Cooper
01:13:47
a
Anicet Dushime Wa Mungu
01:13:48
both
Anthony Qin
01:13:52
both?
Matt Wolff
01:15:04
A and b
Calvin Laughlin
01:15:05
Both
patricia strutz
01:15:10
(E and F) C
monica hicks
01:17:21
I’m dead
monica hicks
01:17:35
DeMorgan eats eclairs from the trash?
Thanawan A. (Ly-Ly)
01:21:06
I tried putting 1 - 0.75^20 as an answer answer, but it said that it was wrong. Isn’t that the answer?
Thanawan A. (Ly-Ly)
01:21:25
I meant for 3a
Asmaa Sultan
01:21:33
E1 string in any bucket, E2 string in that bucket
Michael Alisky
01:27:15
Thanks!
Asmaa Sultan
01:27:18
Thank u!!
eleanor sigrest
01:27:18
Thank you!
Keely Podosin
01:27:19
Thank you!!
Alberto Mancarella
01:27:26
Thank you!
Juben Rana (he/him)
01:27:28
Thank you
Michael Zhu (he/him)
01:27:32
Can u explain the difference between permutating semi distinct objects and combinations?
abel john
01:27:41
Thank you!
alessia arrigo
01:28:02
slide 80 how did we get from the second to last to the last line please? thank you very much
Mike Wu
01:29:05
So p(F1cF2c…Fkc) = p(buckets 1 to k are all denied strings)
Mike Wu
01:29:21
But this is the same as p(each string hashes to at least k+1 )
Mike Wu
01:29:47
But this is the same as p(string_i hashes to at least k+1)^m cuz the strings are independent trials
Mike Wu
01:30:06
But this is just the (1 - p(string_i hashes to less than k+1))^m
Mike Wu
01:30:18
Which is hen (1 - p1 - p2 - … - pk)^m