# When using normal approximation.... (fast word answer)

• Apr 27th 2006, 08:08 AM
Arbitur
When using normal approximation.... (fast word answer)
When using normal approximation for binomial distribution (z-scores, standard deviation, mean ect...) can you ever put the mean before the other number
so (MEAN-X)/standard deviation?????????
• Apr 27th 2006, 12:55 PM
ThePerfectHacker
Quote:

Originally Posted by Arbitur
When using normal approximation for binomial distribution (z-scores, standard deviation, mean ect...) can you ever put the mean before the other number
so (MEAN-X)/standard deviation?????????

Why would you want to?
• Apr 27th 2006, 01:31 PM
CaptainBlack
Quote:

Originally Posted by Arbitur
When using normal approximation for binomial distribution (z-scores, standard deviation, mean ect...) can you ever put the mean before the other number
so (MEAN-X)/standard deviation?????????

This will change the sign of the z-score, so depending on the table you are
using it will possibly allow you to look up a probability for a non-tabulated z-score, or will give the other tail probability, or ..

But there realy is no point (as far as I can see).

RonL