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riplang
Anybody know about z scores?
I'm sure there are plenty of people here that know about z-scores. Do you have a particular question?
Can you have the same z score in the same set of data? I'm thinking yes because what if you have the same number more than once but not sure
If you know the mean and standard deviation, then you can plug them into \[z = (x - \mu)/\sigma,\] wnere mu is the mean and sigma is the standard deviation. Then the probability distribution in x becomes the standard normal distribution in z.
If you are given a set of data, you can get their sample mean and sample variance, using the formula for a discrete set of data.
If the number of data points is at least thiryt, then the normal approximation to distribution due to the data will be a good approximation.