# Statistics for prescriptions...

#### jccarter1

##### New Member
Ok...

I am working for a National Wildlife Refuge in Arkansas and am needing some help with some statistical work. I have an equation out of a book, along with alot of data, but everytime that I work the equation I find the wrong answer. I have tried working some problems that others have sent me, but I can never come close to their answer with the data that they have given me.

The equation that I am trying to use is...

N=[(t^2)(cv^2)]/[(LE)^2]

N is the number of samples (trying to find out how many plots needed to sample a stand to a desired accuracy)

t, I am told, is the probability or gambling odds.

cv is the coefficient of variation

LE is the limit of error.

If you're wanting to know WHY I need to find this...that's a great question. I am not sure what the outcome of the equation fully means, it was simply handed down to me by a superior here at work. I think that's why I am having so much trouble.

If anyone knows much about this equation, or about anything in relation to it, but I really appreciate any help that could be given.

Thanks.

E

#### elnaz

##### Guest
Hello
if possible you speak clearly
what is this equ?
what do you want?
what is the use of this equ?

Best regards
Elnaz