This document defines and provides examples of measures of central tendency, which are methods used to determine how scores are distributed around the average score. It discusses the normal distribution and how measures like mean, median, and mode are used. Specifically, it shows how to calculate the mean by adding all scores and dividing by the total number. To find the median, the scores are ordered from lowest to highest and the middle number is identified. The mode is the number that occurs most frequently. Examples are provided to demonstrate calculating the mean, median, and mode of sample test score data sets.

1. MEASURES OF
CENTRAL TENDENCY
By Jhonna M. Barrosa

2. MEASURES OF CENTRAL
TENDENCY
- are methods to determine how scores
cluster- that is how they are distributed
around a numerical representation of the
average score.

3. • One common typed of distribution used in
assessment is called a normal distribution
Normal Distribution
Represents the way test scores would fall if a
particular tests is given to every single student of the
same age or grade in the population for whom the
test was designed.

4. • A teacher can see how each student performed in a
test, and what type of performance or score
indicated average, what score is considered
excellent, and what score is considered poor.
• To determine this, the teacher must decide what is
considered average for specific set of data
• One way to look at a specific set of data is to…

5. RANK
-The ordinal number of a value
in a list arranged in a specified order.
• Rank scores from highest to lowest

6. To know the Rank…
1. Arrange the data in order
2. Tallying the frequency of each score.
3. Rank scores from highest to lowest

7. GIVEN: TEST SCORES OF 25 STUDENTS IN
SCIENCE
80 87 87 90 80
95 90 80 97 87
85 87 87 90 95
87 85 87 87 85
98 87 75 85 85

8. Arrange the data in order
75 80 80 80 85 85 85 85 85 87
87 87 87 87 87 87 87 87 90 90
90 95 95 97 98
75- 1 87 – 9 97- 1
80 – 3 90 – 3 98 - 1
85 – 5 95 – 2 Total 25
Tallying the frequency of each score

9. Rank scores from highest to
lowest
SCORES TALLY FREQUENCY (f)
98 I 1
97 I 1
95 II 2
90 III 3
87 IIIII-IIII 9
85 IIIII 5
80 III 3
75 I 1
Total 25

10. MEAN
- Also known as the average. The mean is
found by adding up all of the given data and
dividing by the number of data entries.
FORMULA :
∑X
n
X =
Where x = individual score
n = sample size

11. • GIVEN: FIND THE MEAN SCORE OF THE
TEST SCORES OF 15 STUDENTS IN SCIENCE
80 87 87 90 80
95 90 80 97 87
85 87 87 90 95

12. MEAN
FORMULA :
∑X
n
80 +87+87+ 90+ 80+ 95 +90+ 80+ 97+87+
85+ 87+87+90+95
X =
Where x = individual score
n = sample size
25
X =
1,317
25
X = 52.68
X =

13. MEDIAN
- The median is the middle number.
TO GET THE MEDIAN:
1.First you arrange the numbers in order from
lowest to highest,
2. Then you find the middle number by
crossing off the numbers until you reach the
middle.

14. FIND THE MEDIAN
• GIVEN: TEST SCORES OF 15 STUDENTS IN
STATISTICS
33 54 44 53 30
49 46 44 32 44
35 57 43 56 29

15. STEPS IN FINDING THE MEDIAN
1. Arrange the numbers in order from lowest to
highest
29,30,32,33,35,43,44,44,44,46,49,53,54,56,57
2. Find the middle number
MEDIAN = 44
X
~
symbol
If even,
N+1
2
x=
~
Or the average of two
middle scores (ex. 44+44/2)

16. MODE
- This is the number that occurs most often.
ˆ symbol
Example:
- Find the mode of the following data:
78 56 68 92 84 76 74 56 68 66 78 72 66
65 53 61 62 78 84 61 90 87 77 62 88 81
The mode is 78. UNIMODAL DISTRIBUTION
x
If many Bimodal (2)
Trimodal (3)
Multimodal (4+)

17. THANK YOU  !