Secondary data refers to data that was originally collected by other sources for different purposes and is now available for reuse. Some key advantages of secondary data include that it is cheaper and more quickly obtainable than primary data, and may be available when primary data cannot be collected. However, secondary data also has disadvantages like often not fitting the exact needs of the research, uncertainty around accuracy, and potential outdatedness. Proper evaluation of secondary data is important and involves assessing availability, relevance, accuracy, and sufficiency. This evaluation process aims to determine if the secondary data meets the research objectives and can address potential issues like using different measurement units or concepts than needed.

1. Secondary data is the data that have been already collected by and readily available from
other sources. Such data are cheaper and more quickly obtainable than the primary data and
also may be available when primary data can not be obtained at all.
Advantages of Secondary data
1. It is economical. It saves efforts and expenses.
2. It is time saving.
3. It helps to make primary data collection more specific since with the help of
secondary data, we are able to make out what are the gaps and deficiencies and what
additional information needs to be collected.
4. It helps to improve the understanding of the problem.
5. It provides a basis for comparison for the data that is collected by the researcher.
Disadvantages of Secondary Data
1. Secondary data is something that seldom fits in the framework of the marketing
research factors. Reasons for its non-fitting are:-
a. Unit of secondary data collection-Suppose you want information on
disposable income, but the data is available on gross income. The information
may not be same as we require.
b. Class Boundaries may be different when units are same.
Before 5 Years After 5 Years
2500-5000 5000-6000
5001-7500 6001-7000
7500-10000 7001-10000
c. Thus the data collected earlier is of no use to you.
2. Accuracy of secondary data is not known.
3. Data may be outdated.
Evaluation of Secondary Data
Because of the above mentioned disadvantages of secondary data, we will lead to evaluation
of secondary data. Evaluation means the following four requirements must be satisfied:-
1. Availability- It has to be seen that the kind of data you want is available or not. If it is
not available then you have to go for primary data.
2. Relevance- It should be meeting the requirements of the problem. For this we have
two criterion:-
a. Units of measurement should be the same.
b. Concepts used must be same and currency of data should not be outdated.
3. Accuracy- In order to find how accurate the data is, the following points must be
considered: -
a. Specification and methodology used;
b. Margin of error should be examined;
c. The dependability of the source must be seen.

2. 4. Sufficiency- Adequate data should be available.
Robert W Joselyn has classified the above discussion into eight steps. These eight steps are
sub classified into three categories. He has given a detailed procedure for evaluating
secondary data.
1. Applicability of research objective.
2. Cost of acquisition.
3. Accuracy of data.
http://socialscience.stow.ac.uk/psychology/psych_A/george/primary_secondar
y.htm
Primary data are those that you have collected yourself, whereas secondary data
originate elsewhere. Generally, you will find that you are expected to collect primary
data when using quantitative methods, but that secondary data are more acceptable
when you are using a qualitative method. This is because there are certain common
aspects of qualitative research which involve only secondary data, such as the study
of television or newspaper discourses. If you wanted to understand the nature of the
representation of Romany people on television, you wouldn’t make your own
television programmes! You would use those which exist, and they would form [your]
secondary data (Forshaw, 2000).
A secondary data research project involves the gathering and/or use of
existing data for purposes other than those for which they were originally
collected. These secondary data may be obtained from many sources,
including literature, industry surveys, compilations from computerized
databases and information systems, and computerized or mathematical
models of environmental processes.
Secondary Data
What Is Secondary Data?
o Data may be described as Primary or Secondary
 Primary data - collected by the researcher himself
 Secondary data - collected by others to be "re-used" by the
researcher
What Form Does Secondary Data Take?
o Quantitative Sources
 Published Statistics:
 National Government Sources
 Demographic (Census, Vital Statistics, Cancer
Registrations)
 Administrative (by-product of Government)
 Collected by Govt. Depts. overseen by ONS
(eg. employment, prices, trade, finance)
 Government Surveys (input to Government)

3.  General Household Survey (GHS)
 Family Expenditure Survey (FES)
 Labour Force Survey (LFS)
 Family Resources Survey (FRS)
 Omnibus Survey
 Local Government Sources
 Planning Documents
 Trends Documents (eg former Strathclyde Social
Trends and Economic Trends)
 Other Sources
 Firms & Trade Associations eg Society of Motot
Manufacturers & Traders (SMMT)
 Market & Opinion Research eg Gallup, NOP,
SCPR System 3
 Trade Unions, TUC, STUC
 Professional Bodies eg CIPFA (Chartered Institute
of Public Finance & Accountancy) provides a
Statistical Information Service re Local
Government Statistics
 Political Parties
 Voluntary & Charitable Bodies eg Low Pay Unit,
SCF (Save the Children Fund), Rowntree
Foundation
 Academic & Research Institutes eg
 Micro-Social Change Research Centre
(MSRC) at Essex Uni
 National Institute for Economic & Social
Research (NIESR)
 Institute for Fiscal Studies (IFS)
 International Sources
 EU, OECD, World Bank, IMF
 Non-Published / Electronic Sources
 Data Archives eg the Data Archive At Essex
 Data Sub-Setting Service On Tape, Disk, Postal
Or Via Janet
 On-Line Access To National Computing Centres
 MIMAS (Manchester Information & Associated
Services)
 EDINA (Edinburgh)
 International Sources on Internet & Web
o Qualitative Sources
/ Sources for Qualitative Research:
 Biographies - subjective interpretation involved
 Diaries - more spontaneous, less distorted by memory lapses
 Memoirs - benefit/problem of hindsight

4.  Letters - reveal interactions
 Newspapers - public interest & opinion
 Novels & Literature In General - eg Atkinson's tribute to
usefulness of Gordon's "Dr Novels"; McLelland's study of
achievement motivation in different cultures via children's stories
& folktales
 Handbooks, Policy Statements, Planning Documents, Reports,
Historical & Official Documents (Hansard, Royal Commission
reports) etc. n.b Marx's use of Factory Inspectors reports in
developing his theories of the labour process
Ways of Using Secondary Sources
o Exploratory phase - getting ideas
o Design Phase - definitions & sampling frames, question wording
o Supplement to Main Research
 - Re-Enforcement &/Or Comparison
o Main Mode of Research
 - Direct Data Collection Impossible
 - Or Costly & Time Consuming
Limitations of Secondary Data
o Collected For A Different Purpose
o Problem of Definitions
o Problem of Comparability Over Time
o Lack of Awareness of Sources of Error/Bias
o Has the Data Been "Massaged"?
o What Do The Statistics Really Mean?
 Eg. Health, Crime, Unemployment
o Limitations of Survey Data
 Representativeness
 Validity of Responses
o Limitations of Documents
 Documents "Construct" As Well As Report Social Reality
How to Search & Use Secondary Sources?
o Documents - Bibliographic Skills, Use of Keywords, Boolean Operators
o Published Statistics
 Guide to Official Statistics
 Digests & Abstracts
 Primary Publication
o Electronic Sources
 Biron
 Gateways - SOSIG, BUBL
 Search Engines - Infoseek, Alta Vista, Webcrawler etc.
SOURCE: RMS - the Research Methods Server in the Division of Social Sciences,
School of Law and Social Sciences, Glasgow Caledonian University, Glasgow.

5. Forshaw, M (2000) Your Undergraduate Psychology Project: A BPS Guide Blackwell
Publishing