lyric © 2017 Lawrence M. Lesser
may sing to the tune of “Material Girl” (Peter Brown and Robert Rans, popularized by Madonna)
Data values normally are
no more far away
Than 3 standard deviations
from the mean displayed.
And within 2 deviations, 19 of 20 lie, that’s right!
And within 1 deviation, 2/3 are confined,
‘Cause we are living in an empirical world
and I need an empirical tool.
You know that we are living in an empirical world
and I use the empirical rule!
If I think a population
looks bell curve to me,
The rule helps tag outliers like a
z-score more than 3.
But if the population may not
take the normal shape (no way!),
Frequencies that you expect can
help you ascertain