3.1 Measures of Central Tendency: Mean
- The average.
- Used when data are quantitative and the frequency distribution is roughly symmetric.
- The sum of all the values of the variable (in the data set), divided by the number of values / observations. (Another way of saying it: add up all the observations and divide by the number of observations)
- Population mean (mew) = a parameter
- Sample mean (x-bar) = a statistic
Calculate Mean using calculator:
- Stat, Select #1, Enter
- Enter data in L1
- Press Stat, highlight Calc, and select #1: 1-Var Stats, Enter
- Press 2nd then 1 to insert L1 under "List" and press Enter
- The mean for population and sample is shows as x-bar