Hello Nurse Toby.
The problem seems to be the terminology
Let be the variance of one observation whether thats or ....
It's the variance of each one of them.
NOW the sample mean is
and the variance of is
and the st deviation of is
I first of all apologize if this is the wrong category. This is for a Statics class at college level, but basic statistics.
I am really having a hard time and confusing myself when it comes to the standard deviation and variations. The formulas (do the best I can without the keys needed on the keyboard) are:
O2m = O2 squared / N - this is variance
Om = this is standard deviation (standard deviation / N squared = standard deviation)
When given a problem are we be given one or the other to calcuate and then continue with the rest of the steps. For example if I am given the standard deviation of 8 and my N = 10 then 8/10 = .80 so this would be my standard deviation.
Would I also then calcuate a variance or or is that only if you are given the variance in the problem you would then use the formula to determine your variance.
This is the only part I am having a really hard time grasping. Ugh.
Thanks for your help!!