Literature review is an important section of the research paper and a lot of hard work is needed for making a proper literature review. Literature review will give an insights about the different work already been done in the similar field of study. It will also work as a rich source of information for doing research.
There are two kinds of data can be collected from the field. One is the primary data and another is secondary type of data. Primary data are the fresh data collected directly from the field. They are first hand data. Since primary data are collected specially for a particular purpose, extra care is taken to collect all the required data with required degree of accuracy. Primary data are reliable, complete and fresh. Primary data are costly. Their collection consumes more time and labor than the collection of secondary data, especially when the population is vast. If an investigator collects information regarding births and deaths directly from the people, the data are primary data. Important methods of collecting primary data are- (i) Direct personal interview (ii) Indirect personal interview (iii) Information through correspondents (iv) Method of questionnaire (v) Method of schedule.
Secondary data are the data which the investigator does not collect directly from the field. They are the data which he borrows from others who have collected them for some other purposes. Since secondary data are primarily collected for some other purpose, they may not contain all the required information. The degree of accuracy may be different. They, generally, are not as dependable as primary data. Secondary data are cheap. Specially, when the population is vast and funds available are meager, secondary data are preferred.
(A) Published Sources-
1) Reports and publications of Central and State Government Departments.
2) Reports and publications of international bodies such as UNO, IMF etc.
3) Publications of Banks, Research Institutions, Administrative Offices etc.
4) Magazines and News papers.
(B) Unpublished Sources-
1) Reports maintained at Government Offices, Municipal Offices etc.
2) Records maintained by Research Institutions, Research Scholar etc.
Literature review does not only mean collection of data. You need to collect quality information about the previous works already been done in the similar field of research. That means in literature review the collected information will mostly be of secondary types. You need to do through study of all available research dossiers, journals, magazines and all other available papers to review similar research works. A good literature review will increase the gravity of your research paper and it will help you in giving the direction of your research.