Question

Intro to Statistics:

\[\mu=\sum xP(x)\]
\[\mu\] is the expected value of x
So would I add the x values and P(x) values and then multiply them to get \[\mu\]?

x: 0 1 2 3 4 5

P(x): 0.237 0.396 0.264 0.088 0.015 0.001

Answer 1

multiply corresponding x and p(x) values,
like 0*0.237+1*0.396 .......

Answer 2

you would multiply 0 by 0.237 add it to 1 times .396 add it to 2 times 0.264 etc... the sum would be u

Answer 3

oh ok. It seemed too simple

Answer 4

Thanks

Answer 5

welcome ^_^

Answer 6

for the standard deviation I have the equation
\[\sigma=\sqrt{\sum(x-\mu)^2P(x)}\]
So, here I do:
\[0-\mu=-1.253\]
\[1-\mu=1-1.253=-.253\]
\[2-\mu=2-1.253=.747\]
\[3-\mu=3-1.253=1.747\]
\[4-\mu=4-1.253=2.747\]
\[5-\mu=5-1.253=3.747\]
square each solution then multiply to P(x), then add those solutions up

Answer 7

yes!
finally take square root then.

Answer 8

oh yes of course. Thank you!

Answer 9

how do I make a table in latex? I have to submit my work electronically and a table would make it easier.

Answer 10

I couldn't find it here
http://en.wikipedia.org/wiki/Help:Displaying_a_formula#Diagrams_in_TeX

Answer 11

let me search.

Answer 12

http://en.wikibooks.org/wiki/LaTeX/Mathematics

Answer 13

maybe write in matrix form .....of nX2
i'll look up something specifically for table

Answer 14

oh ok, thanks

Answer 15

http://openstudy.com/users/accessdenied#/updates/4fa5b375e4b029e9dc35a2cf

Answer 16

\hlines
what does that do?

Answer 17

I think I get it. I'll just use \\ \hlines
before i move on to the next line. Makes sense

Answer 18

ok and
http://en.wikibooks.org/wiki/LaTeX/Tables

Answer 19

oh perfect! There's the explanations for \hlines. Thanks! =D