This lesson is all about the measures of central tendency. It discusses the mean, median and mode.

1. 1
Measures of Central Tendency
Marietta A. Paje
Subject Teacher

2. 2
Measures of Central Tendency
A measure of central tendency is a
descriptive statistic that describes the
average, or typical value of a set of scores
There are three common measures of
central tendency:
the mean
the median
the mode

3. 3
The Mean
The mean is:
the arithmetic average of all the scores
(X)/N
The mean of a population is represented by
the Greek letter ; the mean of a sample is
represented by X

4. 4
Calculating the Mean
Calculate the mean of the following data:
37 37 24 28 43 44 36 41 33 27
Mean =
37+37+24+28+43+44+36+41+33+27
10
Mean = X = 35

5. 5
The Median
The median is simply another name for the
middle value

6. 6
How To Calculate the Median
Conceptually, it is easy to calculate the
median
Arrange the data from lowest to highest
Find the score in the middle
middle = (N + 1) / 2
If N, the number of scores, is even the median
is the average of the middle two scores

7. 7
Median Example
What is the median of the following scores:
37 37 24 28 43 44 36 41 33 27
Sort the scores:
24 27 28 33 36 37 37 41 43 44
Determine the middle score:
middle = (36 + 37) / 2 = 36.5
Middle score = median = 36.5

8. 8
The Mode
The mode is the score that occurs most
frequently in a set of data

9. 9
Bimodal Distributions
When a distribution has two “modes,” it is called
bimodal

10. 10
Multimodal Distributions
If a distribution has more than 2 “modes,” it is
called multimodal

11. 11
Mode Example
Arrange the data from lowest to highest:
24 27 28 33 36 37 37 41 43 44
Find the mode:
Mode = 37