working out S.D. through formula?

[vce01]

it takes too long, would they ask us to do this in an exam?

(unless theres another way)

[onlyfknhuman]

I think its likely in the exam...

[BiG DaN]

sd in what context?
z= (x -m)/ sd?

[Lulu]

are you referring to the discrete probability SD? or that huge normal distribution formula

[vce01]

are you referring to the discrete probability SD? or that huge normal distribution formula

oh yeah sorry, should've specified. the latter. where you're given a table and stuff, and have to work out the mean before.

[Lulu]

the one where they give you a table is discrete probability...

and i'm pretty sure it is examinable on exam 1. must say, i hate multiplying and adding all those decimals too though

[bturville]

yes, i'm pretty sure you need to remember the huge normal dist. formula, specifically which bits go where...but not using it for calculations. the calculator does that.

[bec]

i doubt it. i hope not, anyway! my teacher mentioned it in class once i think but otherwise i've never seen a question on it...i don't think it's on the study design?
has anyone been specifically told that they have to know it?

[bucket]

do you work out the sd by finding the square root of ?

I haven't done any questions like that for a long time and I'm sort of forgetting :S

[vce01]

okay thanks, and one more thing, i don't want to create a new thread...we don't get a CND table right? so anything to do with standard normal distribution and inv normal distribution won't be tested on exam 1?

[BiG DaN]

okay thanks, and one more thing, i don't want to create a new thread...we don't get a CND table right? so anything to do with standard normal distribution and inv normal distribution won't be tested on exam 1?

if ur asked to find
Pr(z>0.5)
they will give u Pr(z<0.5)=0.xxxx
and u work it out from there

[dekoyl]

okay thanks, and one more thing, i don't want to create a new thread...we don't get a CND table right? so anything to do with standard normal distribution and inv normal distribution won't be tested on exam 1?

If by CND table you mean those huge tables with decimals everywhere then no.

And bucket: Yes that's right.

[vce01]

ahh okay, thnx big dan + dekoyl

[Mao]

you will be expected to know the 68-95-99.7 rule.