1. ©G Dear 2009 – Not to be sold/Free to use
Summary
Statistics
General Mathematics
Preliminary
Calculating
the Mean
Stage 6 - Year 11
Press Ctrl-A
©G Dear 2009 – Not to be sold/Free to use

2. Mode (1/1) The Mode is a measure of central tendency
The Mode is the most common score,
The score with the highest frequency.
Example 1: 2, 3, 4, 5, 7, 7, 8.
Mode = 7
Example 2: 2, 3, 4, 5, 7, 7, 8, 8.
Mode = 7, 8
Polymodal

3. When to use Mean, Median & Mode (1/2)
The Mean is NOT a good measure of central tendency if we have outliers.
E.g.
2, 3, 4, 4, 6, 7, 9
Mean = 5
2, 3, 4, 4, 6, 7,44
Mean = 10
One extreme value has doubled the mean.
Use the Median
= 4

4. When to use Mean, Median & Mode (2/2)
The Mean and Median may NOT be a good measure of central tendency if we are using Discrete data.
E.g.
Shoe Sales
Shoe Sizes: 6, 6, 8, 9, 9, 9.
Mean = 7.8
Median = 8.5
In terms of sales the Mode is meaningful.
Mode = 9