The z-score
The number of standard deviations from the mean is called the z-score and can be found by the formula
x – m
z = ——–
s
x is the value
m is “mu”, the mean
s is standard deviation
Z Scores
Tag: statistics
Empirical rule – The 68-95-99.7 Rule
Empirical rule
The 68-95-99.7 Rule
For Normal Distributions
This rule applies generally to a variable X having normal (bell-shaped or mound-shaped) distribution with mean "mu" (the greek letter) and standard deviation "sigma" (the greek letter). However, this rule does not apply to distributions that are not normal.
Frost, Holloway H. – Commander
“There are three kinds of lies – lies, damnable lies, and statistics.”
- Also attributed to Mark Twain
