Transcript Measures of Central Tendency

Measures of Central
Tendency
By Marty Knight
Introduction
In school we choose a student from
each homeroom to represent us in
student council meetings.
One student represents the
opinions of many.
Overview
In mathematics we choose one
number to represent many in a
set of data.
There are three ways to choose:
Mean.
Median.
Mode.
The Mean

Sometimes called the average.

Best represents data with a small range.
To calculate the mean, add the numbers
up and divide by the number of values.

Try One
Find the mean of these test scores:
86, 80, 90, 88.
86 + 80 + 90 + 88 = 344.
344 / 4 = 86.
The mean is 86.
The Median

The median is the value in the middle.

Arrange your data in order.

Then pick the middle one.
1 3 6 7 7 8 9.
Her Height Is the Median
The Mode

The item repeated most often is the mode.
There
can be more than one mode.
There
might be no mode at all!
Examples
1 1 1 2 3 5 6 6 – The mode is 6.
1 1 1 2 2 2 3 – The modes are 1 and 2
1 2 3 4 5 6 – There is no mode
Mean Median Mode