Expected Value: E(X)

Expected value of a random variable

Uploaded by: khanacademy
Tags for this video: expected value E(X) population mean

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ur awesome! ( 11 months ago by jsteh22)

ur awesome!

@khyer123 from uwo ... ( 11 months ago by ismaelOnTheGround)

@khyer123 from uwo ?

Khan you prove ... ( 11 months ago by TheJrDream)

Khan you prove that south asians are indeed good at math. Way to go!

Well, it 's ... ( 10 months ago by Anthony42ly)

Well, it 's AWESOME, or it's nothing.

Hey I was wondering ... ( 9 months ago by jsstevely)

Hey I was wondering how to find the frequency of outcome when you don't have the use of technology. So without excel/graphing calculator how would you find the frequency?

4:19 - number of ... ( 9 months ago by cmason3344)

4:19 - number of heads after 6 tosses. lol

THANKS! great ... ( 9 months ago by voidstuff)

THANKS! great explanations Khan! I love your teaching style

thanks dog ( 9 months ago by paulceltics)

thanks dog

Thank you very ... ( 7 months ago by thesixthsense1)

Thank you very much sal .. Superb video as always..

Hey! GIANT DOUBT... ... ( 6 months ago by ivankeri)

Hey! GIANT DOUBT.... How come the Expected Value won't be really the "most probable/expected value(s)" in some cases??????
(As said in 14:00 ) How could you interpret as an "Expected value" a non-probable value when it results form having very probable values around it?

YOU ARE THE BEST. ... ( 6 months ago by dany2tah2)

YOU ARE THE BEST. thank you. thank you. thank you.

so smart! ( 6 months ago by mumu8881)

so smart!

@khyer123 based on ... ( 5 months ago by PoeRilla)

@khyer123 based on what you just saud, we may go to the same school!! lol

#NUM! #NUM! #NUM! # ... ( 5 months ago by chikentori)

#NUM! #NUM! #NUM! #NUM! #NUM! #NUM! #NUM! #NUM! #NUM! #NUM!
lol, I need to learn how to use MSexcel now!

PLEEESSE make ... ( 4 months ago by brian5446)

PLEEESSE make videos for quantum mechanics. This is so close, carries the base ideas, but using them with electrons looses me.

Great video, thanks ... ( 4 months ago by jaimitoteran)

Great video, thanks for uploading!
Two questions though...
The first value, when you multiply the probability by 0 (no heads), even if you multiply it by 0=0, you still have to put that probability (0.09278) in the SUM.
Second, why do we get the Expected value of 3, while when you calculate the arythmetic mean is 3.5? Should they both be the same? I really appreciate your response, thanks a lot!

the video is ... ( 4 months ago by 00000gerat)

the video is admitted alright, though it doesn't really help with applying this to more forms in probability theory if you already understand this basic concept. real problem? if he says "arithmetic (n.) mean" one more time I will have to randomly distribute tacks all over his tongue.

you should get ... ( 3 months ago by petershayo)

you should get paid for this, seriously

@chikentori ... ( 3 months ago by petershayo)

@chikentori lololol i was saying them out loud when he was scrolling
#NUM! #NUM! #NUM! #NUM! #NUM! #NUM! #NUM! #NUM!

@petershayo donate ... ( 3 months ago by discy12345)

@petershayo donate! khanacademy . org/contribute

Option premiums... ... ( 3 days ago by MrKernkraft4000)

Option premiums... :)