What's with the Greek?

What's with the Greek? (4)

Friday, 22 January 2010 00:00

Mu = Mean



The Greek lowercase letter for "M" (pictured above on the right) is pronounced as "mew."

This symbol represents the mean of a data set. 

Friday, 22 January 2010 20:22

X Bar = Sample Mean



X Bar (pictured below under Sample Mean) is simply the mean of a given set of sample values.

As you will notice, "X Bar" is the same as the POPULATION MEAN, merely reexpressed. 

Read Sample Mean vs. Population Mean for more information. 



\[ \sigma \]

This symbol, the lowercase "sigma," represents the POPULATION STANDARD DEVIATION

The formula to calculate the population standard deviation is:

Friday, 22 January 2010 19:48

Capital Sigma = Sum


"SIGMA" means the SUM:

The "sum of what?"  The sum of a set of values:




(1 + 2 + 3 + 4 + 5) = 15