Sample List of Symbols and Their Meanings

In the sample list that follows, note the use of uppercase and lowercase letters in the notation of population (parameter) and sample (statistic), respectively. Be sensitive to population versus sample data and results, and do not confuse the notation.

A list like the one illustrated below may provide a handy reference as you proceed through the course and perhaps help you focus on essential points when you prepare for the exams. Including a cross reference to pages in the text may also be helpful.

 

 

Symbol/Formula

 

Meaning/Description


X





Observation in a population

x



Observation in a sample

μ (lowercase Greek mu)



Population mean

 



Sample mean

σ  (lowercase Greek sigma)



Population standard deviation

Σ (uppercase Greek sigma)



Summation

N



Number of items in a population

n



Number of items in a sample

 

 

Formula for sample mean