1. Methods of Data Collection
Ravindra J. Mandale
Assistant Professor
Department of CSE, RIT
2. Contents
Types of data
Methods of primary data collection
Methods of secondary data collection
3. Types of Data
Types of data:
Primary data-
-data which are collected afresh
Secondary data-
-data which have already been available
4. Methods of primary data collection
Observation method
Interview method
Questionnaires
Schedules
Warranty cards
Distributor or store audits
Pantry audits
Consumer panels
Use of mechanical devices
5. Methods of primary data collection
1) Observation method
Used in studies relating to behavioral sciences
Information is collected by investigator’s own
observation without asking from the respondent. eg.
study relating to consumer behavior.
Advantages
Subjective bias is eliminated
Information relates to what is currently happening; it
is not complicated by either past behavior or future
intentions.
Limitations
Expensive
Provided information is very limited
Unforeseen factors may interfere with the
observational task.
6. Methods of primary data collection
Observation method
Types
i) Uncontrolled
Observation takes place in the natural setting
ii) Controlled
Observation takes place according to definite
pre-arranged plans involving experimental
procedures
Carried out in labs.
7. Methods of primary data collection
2) Interview method
It involves presentation of oral-verbal talks
and reply in terms of oral-verbal responses.
Two types
a) Personal interview
b) Telephone interview
8. Methods of primary data
collection
a) Personal interview
Two parties: interviewer and
interviewee(respondents)
Usually the interviewer initiates the interview and
collects the information.
Direct personal investigation
Eg. HR interview
Indirect oral investigation
Eg. Commissions or committees appointed by Govt.
Structured interview
Involve the use of a set of predetermined questions
and standard technique of recording information
Unstructured interview
Do not follow a set of predetermined questions and
standard technique of recording information
9. Methods of primary data
collection
Merits:
More information and in greater depth can be
obtained
Non-response generally remains very low
Personal information can be easily obtained under
this method
Demerits:
Expensive method
More time consuming when the sample is large
There remains the possibility of the bias of
interviewer as well as that of respondent; there also
remains the headache of supervision and control of
interviewers.
10. Methods of primary data collection
b) Telephone interview
Conducted on telephone itself
Not a very widely used method but plays important role in
industry surveys.
Merits:
It is faster than other methods i.e. a quick way of obtaining
information
It is cheaper than personal interview method
High rate of response than mailing method
No field staff is required
Demerits:
Method is restricted to respondents who have telephone
facilities
Possibility of the bias is more
11. Methods of primary data collection
iii) Questionnaires
- Quite popular and particularly used in big enquiries
- Adopted by private individuals, research workers,
private and public organizations and by
governments.
- In this, a questionnaire is sent(by post) to the
persons concerned with a request to answer the
questions and return the questionnaire.
- Sometimes questionnaire is mailed to respondents
who are expected to read and understand the
questions and write down the reply in the space
provided in the questionnaire itself.
Eg. Alumni survey by CSE
This method is extensively used in business and
economic surveys.
12. Methods of primary data collection
Merits:
Low cost even when the universe is very large and
is widely spread geographically.
Respondents have enough time to give well thought
answers
It is free from the bias of the interviewer; answers
are in respondents own words
Demerits:
Low rate of return of the duly filled in questionnaire
It can be used only when respondents are educated
and cooperating
The control over questionnaire is lost once it is sent.
Slowest of all
13. Methods of primary data collection
iii) Schedules (proforma containing a set of
questions)
- Very much like to the questionnaire with little
difference is that schedules are being filled in by the
enumerators who are specially appointed for the
purpose.
- These enumerators along with schedules, go to the
respondents, put to them the questions from the
proforma in the order the questions are listed and
record the replies in the space meant for the same in
the proforma.
- Expensive but fairly reliable.
- Conducted by government eg. Population survey
14. Methods of primary data collection
5) Warranty cards
- Are postal sized cards used by dealers to collect
information about their products.
- The information is printed in the form of questions on
the card which is placed inside the package along
with the product with a request to consumer to give
answers and post it back to the dealer.
6) Distributor or store audits
- Are performed by distributor through their salesman
at regular interval
- Distributor collect the information to estimate the
market size, market share, etc.
- Data is collected based inventories on hand by
observation
15. Methods of primary data collection
7) Pantry audits
Objectives is to find out what types of consumers
buy certain product’s and certain brands
In this, the investigators collects an inventory of
types, quantities and prices of commodities
consumed.
8) Consumer panels
An extension of the pantry audits on a regular basis,
where a set of consumers are arranged to come to
maintain detailed daily records of their consumption
and same is made available to investigator on
demands.
16. Methods of primary data collection
9) Use of mechanical devices
Widely made to collect information by way of indirect
means.
Eye camera, motion picture camera and audiometer
used by modern big business houses.
Eye cameras are used to record the focus of eyes of
a respondent on a specific portion of a sketch or
diagram or written material. Such an information is
useful in designing advertising material.
17. Methods of secondary data collection
May either be published or unpublished data.
Published data are available in -
Various publications of central, state governments
Various publications of foreign governments or
international bodies
Technical and trade journals
Books, magazines and newspapers
Reports prepared by research scholars, universities,
economics, etc.
Public reports and statistics, historical documents
Unpublished data are available in -
Diaries, letters, unpublished biographies and may be
available with scholars and research workers, trade
associations and other public/private individuals and
organizations.
18. Methods of secondary data
collection
Researcher must be very careful in using secondary
data.
He must make a scrutiny because it is possible that
the secondary data may be unsuitable or may be
inadequate in the context of the problem which the
researcher wants to study.
Systematic bias results from errors in the sampling procedures and it cannot be reduced or eliminated by increasing sample size. If the measuring device is constantly in error, it will result in systematic bias.