Learn how to organize and present data using frequency distribution and graphs.

1. Be
Organized

2. How do we
present the results
of a study?

3. Textual Form
Tabular Form

4. Graphical Form
Horizontal Bar Graph
Vertical Bar Graph
Multiple Bar Graph

5. Graphical Form
Line Graph
Pie Graph
Picture Graph

6. Let’s say you asked your classmates’
score in your 1st Geometry Test
RAW DATA How do you organize
the raw data?

7. Frequency Distribution
is the organization of raw data in
table form, using class intervals and
frequencies
Class Interval
is the range into which
data are divided
Frequency (f)
number of data values
that fall in the range

8. How do you
construct a
frequency
distribution table?

9. 1. Identify the highest value (HV) and the
lowest value (LV).
2. Calculate the range: R = HV – LV
R = 100 – 70 = 30

10. 3. Find the number of class intervals,
using Sturge’s formula:
K = 1 + 3.3 log N
K = number of class intervals
N = total number of observations
K = 1 + 3.3 log 50
K = 6.61
K = 7 (rounded to the nearest whole number)

11. 4. Determine the class width.
Class width = R (number of data)
K
Class width = 30 = 4.28
7
Class width = 5 (next whole number)
5. The beginning of the 1st class interval
(lower class limit) should be near the lowest
value and be a multiple of the class
width.

12. lower class limit
upper class limit
70 – 74 (70,71,72,73,74)
75 – 79 Tip: lower class limit
80 – 84 should be a multiple of
the class width
85 – 89
90 – 94 Class limits do
not overlap.
95 – 99
100 – 104

13. 7. Obtain the class boundaries.
Subtract 0.5 from each lower class
limits and add 0.5 to each upper limits.
70 – 74 69.5 – 74.5
75 – 79 74.5 – 79.5
80 – 84 79.5 – 84.5
85 – 89 84.5 – 89.5
90 – 94 89.5 – 94.5
95 – 99 94.5 – 99.5
100 – 104 99.5 – 104.5

14. 8. Find the midpoint or class mark of each
class interval.
Class mark = lower limit + upper limit
2
70 – 74 72
75 – 79 77
Class marks
80 – 84 82 also follow the
85 – 89 87 class width.
90 – 94 92
95 – 99 97
100 – 104 102

15. 9. Tally the raw scores and indicate the
frequency for each class intervals.
Or…
=COUNTIF(dataset,”x”)
=COUNTIF(dataset,”x1”)+COUNTIF(dataset,”x2”)
=COUNTIF(C3:G12,”70”)+COUNTIF(C3:G12,”71”)+...

16. 9. Tally the raw scores and indicate the
frequency for each class intervals.
Count the
highlighted
cells.
Highlight the
data set.

17. Frequency Distribution Table

18. Task 2 (save file as T1A2_section_surname)
a. The same file (Frequency
Distribution.xlsx) contain Sheets 2
and 3.
b. Construct frequency distribution
tables for the data sets found in
Sheets 2 and 3.
Note: For sheet 3, the data values contain a
decimal point. The class width should be rounded
off to the higher value using the same number of
decimal place as the given data. To get the class
boundaries ±0.05 is used.

19. What are the
different types of
frequency
distributions?

20. Relative Frequency Distribution
It indicates how many percent of the data fall within
each category.
Pf = class frequency x 100%
total frequency
=8/50 =8/50*100
or or
=cell/50 =cell*100

21. Cumulative Frequency Distribution
It shows the accumulation of the frequencies of the
class intervals or categories of data.
Less than cumulative frequency (Cf <)
Greater than cumulative frequency (Cf >)
=42-8
=34-5
=16+5
=21+11

22. Task 2 (continuation)
c. Construct relative frequency
distributions and cumulative
frequency distributions for the data
sets found in Sheets 2 and 3.
Note: Save file as T1A2_section_surname in
your folder located in drive D.

23. How do you graphically
represent the frequency
distribution table?

24. Histogram
It shows vertical bars representing class intervals or
categories on a frequency distribution.
You can change the
properties of the table.
Highlight the
columns.

25. You can change the
color of the bars.
Double click on a bar and it will
show formatting options.
You can also show
boundaries to the bars.

26. Frequency Polygon
It is constructed by plotting the frequencies against the
corresponding class marks, connecting successive
points by means of straight lines.
Create class
marks beyond the
class intervals

27. Minimum: extra class mark
Maximum: extra class mark
Major unit: class width
Double click the values along
the x-axis to format the graph.

28. Task 2 (continuation)
d. Construct histograms and frequency
polygons for the data sets found in
Sheets 2 and 3.
Note: Save file as T1A2_section_surname in
your folder located in drive D.

29. Cumulative Frequency Curve or Ogive
It can be used in estimating the number of cases falling
below a given value within the range distribution.
Identify lower class
boundaries and
add extra LCBs

30. Minimum: extra lower class boundary
Maximum: extra lower class boundary
Major unit: class width

31. Task 2 (continuation)
d. Construct cumulative frequency
curve for the data sets found in
Sheets 2 and 3.
Note: Save file as T1A2_section_surname in
your folder located in drive D.