This document discusses various methods for collecting data for research studies, including documentary sources, field sources, and experimental methods. Documentary sources provide detailed, accurate, and reliable data through published and unpublished reports from primary or secondary sources. Field sources involve collecting data directly from individuals through interviewing or questionnaires. Interviewing allows for consistent data but is time-consuming, while questionnaires are inexpensive but have low response rates. Experimental methods determine cause-and-effect relationships and are used in scientific inquiries. The document also provides formulas for calculating sample sizes from populations with given margin of errors.

1. COLLECTION OF DATA

2.  1. Documentary
- information contained in published
or unpublished reports, statistics, Internet,
magazines, diaries, and so on.
- taken from:
a. Primary
- data gathered are original.
b. Secondary
- data are previously gathered from
an original source, which are computed and
compiled.

3.  DETAILED AND ACCURATE
 MORE RELEVANT
 MORE RELIABLE

4.  2. Field Sources
- include individuals who have
sufficient knowledge and experience
regarding the study under the investigation.

5.  THE DIRECT METHOD
- “interview” method
- face-to-face encounter
Advantage:
- provides consistent and precise
information
- questions may be repeated and
modified
Disadvantage:
- time-consuming, expensive

6.  THE INDIRECT METHOD
- “questionnaire method”
- done by giving prepared relevant
questionnaires to the respondents of the
study
QUESTIONNAIRE
- list of questions which are
intended to elicit answers to the problems
under investigation.

7. Advantage:
- may be mailed or hand-held.
- inexpensive and can cover a wide
area in a shorter period of time.
Disadvantage:
- strong probability of no response
- questions not easily understood
will also probably not be answered.

8.  THE REGISTRATION METHOD
- method of utilizing the existing data
or fact or information, which is kept
systematized by the office concerned
Ex. Registration of births, death, motor,
vehicles, marriages and licenses.

9.  THE OBSERVATION METHOD
- used to collect data pertaining
attitudes, behavior, values and cultural
patterns of the samples under investigation.
- may be taken individually or
collectively

10.  THE EXPERIMENT METHOD
- used to determine the cause and
effect relationship of certain phenomena
under investigation.
- used in making scientific inquiry.

11. where n = sample size
N = population size
e = margin of error
2
1 Ne
N
n



12.  A researcher in Cagayan Colleges would like
to make a survey in the school with a
population of 10,000 students with a margin
error of 10%. How many students must he
take into his sample?

13. 99
)10)(.10000(1
10000
1
2
2





Ne
N
n

14.  Given the population size with their
corresponding margin of error, determine the
sample size of the ff:
1. N = 10,000 , e = 5%
2. N = 5,000 , e = 10 %
3. N = 25,000 , e = 3%
4. N = 30,000 , e = 1%
5. How many sample units must be obtained
from 7,000 CCTians, if 10% margin of error
is used?

15. 385
)05)(.10000(1
10000
1
2
2





Ne
N
n

16. 98
)10)(.5000(1
5000
1
2
2





Ne
N
n

17. 1064
)03)(.25000(1
25000
1
2
2





Ne
N
n

18. 7500
)01)(.30000(1
30000
1
2
2





Ne
N
n

19. 99
)10)(.7000(1
7000
1
2
2





Ne
N
n