Answer of
Question No. 1. (a)
Primary Data and Secondary Data:
Utmost care should be taken while collecting data because
data constitute the foundation on which the superstructure of statistical
analysis is built. The results obtained from the analysis are properly
interpreted and policy decisions are taken.
Hence, if the data are inaccurate and inadequate, the whole analysis may
be faulty and decisions taken misleading.
Statistical
data are of two types
(a) Primary data
(b) Secondary data.
Primary Data: Data which are collected for the first
time for a specific purpose are known as Primary data. Primary data are
obtained by specifically designed system to fulfill the data needs of the
problem at hand. The primary data are those which are collected afresh and for
the first time and thus happen to be original in character. For example, data
obtained in a population census by the office of Registrar General and Census
Commissioner are primary data.
Secondary Data: Data which are collected by someone else,
used in investigation are knows as Secondary data. Data are primary to the
collector, but secondary to the user. For example: Statistical abstract of the
Indian Union , Monthly abstract of statistics,
Monthly statistical digest, International Labour Bulletin (Monthly).
Methods of Collection:
Following are
the important methods of collecting primary data:
(a) Observation Method: It is the most commonly used method
especially in studies relating to behavioural science. In this method
information are sought by way of investigator’s own direct observation without
asking from the respondent. For instant,
in study relating to consumer bahaviour, the investigator instead of asking the
brand of wrist watch used by the respondent may himself look at the watch.
Advantage of Observation Method:
Following are the advantages of observation method:
Ø
Subjected bias is eliminated, if observation is
done correctly.
Ø
The information obtained under this method
relates to what is currently happening, it is not complicated by either the
past behaviour or future intentions or attitudes.
Ø
This method is independent of respondent’s
willingness to respond and as such is relatively less demanding of active
cooperation on be part of respondents as happen to be the case in the interview
or the questionnaire method.
Ø
This method is particularly suitable in studies
which deal with subject, i. e. respondents who are not capable of giving verbal
report of their feelings for one reason or the other.
Disadvantage: However observation
method has various disadvantages:
Ø
It is an expensive method.
Ø
Information provided by this method is very
limited.
Ø
Sometimes unforeseen factors may interfere with
the observational task. At times, the
fact that some people are rarely accessible to direct observation creates
obstacles for this method to collect data effectively.
(b) Interview Method: There are two types of interview method:
(i) Personal Interview: In this method of data collection, there is a
face-to-face contact with persons from whom the information is to be obtained. The interviewer asks them questions
pertaining to the survey and collects the desired information. The information
thus obtained is original in character.
Advantage: The advantages of
personal interview method are as follows:
Ø
More information and too in greater depth can be
obtained.
Ø
Interviewer by his own skill can overcome the
resistance, if any, of the respondents.
Ø
There is a greater flexibility under this method
as the opportunity to restructure questions is always there, especially in the
case of unstructured interviews.
Ø
Observation method can also be applied to
recording verbal answers to various questions.
Ø
Personal information can as be obtained easily
under this method.
Ø
Sample can be controlled more effectively as
there arises no difficulty of missing return, non-response generally remains
very low.
Disadvantages: There are certain
weaknesses of personal interview method:
Ø
It is very expensive method, especially when
large and wide spread geographical sample is taken.
Ø
There remains the possibility of the bias of
interviewer as well as that of the respondents.
Ø
This method is more time consuming, especially
when the sample is large and recalls upon the respondents are necessary.
Ø
Interview at times may also introduce systemic
errors.
Ø
Effective interviews pre-suppose proper rapport
with respondents that would facilitate free and frank response.
(ii) Telephone Interview: This method of collecting information
consists in contacting respondents on telephone itself. It is not a very widely used method, but plays
important part in industrial surveys, particularly in developed regions.
Merits: The chief merits of such
systems are:
Ø
It is more flexible in comparison to mailing
method.
Ø
It is faster than other methods.
Ø
It is cheaper than personal interviewing method.
Ø
Recall is easy, callback are simple and
economical.
Ø
There is a higher rate of response than what we
have in mailing method.
Demerits: It is not free from
demerits:
Ø
Surveys are restricted to respondents who have
telephone facilities.
Ø
Extensive geographical coverage may get
restricted by cost consideration.
Ø
It is not suitable for intensive surveys where
comprehensive answers are required to various questions.
Ø
Possibility of bias of the interviewer is
relatively more.
Ø
Questions have to be short and to the point,
probes are difficult to handle.
(c) Questionnaire Method:
In this method a list of questions pertaining to the survey is prepared and
sent to the various informants by post. The questionnaire contains questions
and provides space for answers. A
request is made to the informants through a covering letter to fill up the
questionnaire and send it back within a specified time. This method is adapted by private individuals,
research workers, private and public organisations and even by govt.
Merits: This method is most
extensively employed in various economic and business surveys. The main merits
are as follows:
Ø
There is low cost even when the universe is
large and is widely spread geographically.
Ø
It is free from the bias of the interviewer;
answers are in respondent’s own words.
Ø
Respondents have adequate time to give well out
answers.
Ø
Respondents who are not easily approachable can
also be reached conveniently.
Ø
Large sample can be made use of and thus the
results can be more dependable and reliable.
Demerits: It is not
free from demerits:
Ø
Low rate of return of the duly filled in
questionnaires, bias due to no-response is often indeterminate.
Ø
It can be used only when respondents are
educated and cooperating.
Ø
There is inbuilt inflexibility because of the
difficulty of amending the approach once questionnaires have been sent.
Ø
The control over questionnaire may be lost once
it is sent.
Ø
There is also the possibility of ambiguous
replies or omission of replies altogether to certain questions, interpretation
of omission is difficult.
Ø
It is difficult to know whether willing
respondents are truly representative.
Ø
This method is likely to be the slowest of all.
(d) Schedule Method: This method of data collection is very much
like questionnaire method, with a little difference which lies in the fact that
schedules are being filled in by the numerators who are specially appointed for
this purpose. These numerators along
with schedules go to respondents put to them the questions from the Performa in
the order questions are listed and record the replies in the space provided.
Numerators explains them the object of the investigation and also removes the
difficulties felt by the respondents.
The numerators should train to perform their job well and the nature and
scope of the investigation should be explained to them thoroughly. The numerators should be intelligent and must
posses the capacity of cross examination in order to find out the truth. This method of data collection is very useful
in extensive enquiries and can lead to fairly reliable results. It is, however very expensive and is usually
adopted in investigations conducted by governmental agencies or by some big
organisations. Population census all
over the world is conducted through this method.
(e) Other methods Of collecting
Data: There are some other
methods of data collection particularly used by big business houses I modern
time:
Ø
Warranty cards
Ø
Distributor or store audits
Ø
Pantry audits
Ø
Consumer panel
Ø
Use of mechanical device
Ø
Project techniques
Ø
Depth interviews
Ø
Contact analysis
Answer of Question No. 2. (b)
Difference between Primary
Data and Secondary Data:
Primary Data: Data which are collected for the first
time for a specific purpose are known as Primary data. For example: Population census, National income collected by
government, Textile Bulletin (Monthly), Reserve bank of India
Secondary Data: Data which are collected by someone else,
used in investigation are knows as Secondary data. Data are primary to the
collector, but secondary to the user. For example: Statistical abstract of the
Indian Union , Monthly abstract of statistics,
Monthly statistical digest, International Labour Bulletin (Monthly).
Some of the basic difference between
Primary and Secondary Data
(a) Primary data are those which are collected
for the first time and thus original in character. While Secondary data are
those which are already collected by someone else.
(b) Primary data are in the form of raw-material,
whereas Secondary data are in the form of finished products.
(c) Primary data are collected directly from
the people related to enquiry while Secondary data are collected from published
materials.
(d) Data are primary in the hands of
institutions collecting it while they are secondary for all others.
Answer of Question No. 4. (a)
Answer of Question No. 4. (a)