12. Collection of Data:
There are two sources of collecting data:
(a) Primary Sources: The data published or used by an organisation which originally collects them are called ‘primary data’. The data in the Population Census reports are primary because they are collected, compiled and published by the Population Census Commission.
(b) Secondary Sources: The data published or used by an organisation other than the one which originally collected them are known as ‘secondary data’. For example, the data in Economic Survey of Pakistan.
Methods of Collection of Primary Data:
(a) Direct Personal Observation, i.e., through individual interviews.
(b) Indirect Oral Investigation, i.e., on evidence of persons or parties suppose to know the facts directly or indirectly.
(c) Registration is the most popular method of collecting data.
(d) Estimates Through Local Correspondents is not a formal collection of data. This method is generally used in crop or land estimates.
(e) Investigation Through Enumerators to get the forms of inquiry filled in from the informants.
(f) Mailed Questionnaire Method.
Methods of Collecting Secondary Data:
(a) Official Sources, i.e., publications of Federal Bureau of Statistics; Ministries of Finance, Trade and Industry, Telecommunication, Education, etc.
(b) Semi-Official Sources, i.e., publications of State Bank of Pakistan, SECP, District Councils, Municipal Committees, etc.
(c) Private Sources, i.e., publication of trade associations, Chamber of Commerce and Industry, etc.
(d) Technical and Trade Journals.
(e) Research Organisations, i.e., universities, Institute of Education and Research, Institute of Development Economics, etc.