Rajasthan Board RBSE Class 11 Economics Notes Chapter 5 Collection of Data
→ Statistical research is a complex process.
→ Collecting data is the fundamental process of the science of statistics.
→ Statistical data is the cornerstone of experimental science.
→ The success of the activities of analysis and interpretation of data is based on the accuracy and techniques of collection of data.
→ Depending on the sources of collecting the data, data can be divided into two parts-
- Primary data
- Secondary data
→ The data which is collected the first time as a fresh data by the investigator himself, is called primary data.
→ Data that has been compiled by another person or organization in the past and those that have
been already published are called secondary data. ‘
→ In primary and secondary data, differences are made on the basis of nature, collector, plan, objective, etc.
→ There are several methods of collecting primary data :
- Direct personal investigation
- Indirect oral investigation method
- Information through correspondence and local residents
- Information through schedules to be filled by the informants
- Information through enumerators
→Direct personal investigation method is suitable for such investigation, where the scope is limited or of local nature.
→ Indirect oral investigation method is the method in which information is not obtained from persons who have direct relationship with the problem, rather data is collected by oral questioning of related third party.
→ Schedules and questionnaires are prepared for collecting data for making the survey.
→ The questionnaires are filled by the person who provides information.
→ Schedules are filled by the enumerators after making enquiries from the informants.
→ The size of questionnaire should be small and the number of questions should be less.
→ Questions should not such that hurt the self-esteem of the person who is providing information; questions which offend the feelings should be avoided.
→ There is considerable difference found between questionnare and a schedule.
→ There are two major sources of secondary data:
- Published Source
- Unpublished Source
→ Under published source various investigation organizations, government departments, etc. collect oral data on various subjects and publish them from time to time.
→ Unpublished source are the data collected by the government or other institutions or individuals (especially investigators), to collect material associated with important subjects but which remain unpublished.
→ There are many shortcomings in secondary data, therefore, it is important to edit it elaborately through critical examination.
→ Every statistical investigation tries to obtain information about the data.
→ There are two methods of statistical investigation. These are:-
- Census Method
- Sample Method
→ When the investigator collects information from all the units and elements, then it is called census method.
→ Population census is an example of census method.
→ The results derived from this method are authentic and reliable.
→ This method is costly, and labour and time involved is also more.
→ Under the sample method, some representative units are selected from the aggregate and . conclusions are derived from the study of those selected units.
→ Time and money are saved through this method.
Three methods for selecting a sample are
- Sampling
- Random sampling
- Stratified sampling.
Collection of Data Class 11 RBSE Notes Important Terms
• Primary data : The data which is collected by an investigator in a new form for the first time by direct interaction with respondents is known as Primary data.
• Secondary Data : Secondary data is that which has been collected earlier by an individual an institution and which has been published.
• Direct Personal Investigation : In this method, the investigator presonally gets in touch with the respondents.
• Indirect Oral Investigation : It is the method in which the information is not obtained from person who have direct relationship with the problem, rather data is collected by orally questioning persons from a third party.
• Questionnaire : Questionnare is the list of questions which is filled by the informants.
• Schedule : A schedule is filled by the interviewer or investigator after asking questions from the informants.
• Census Method : When the investigator collects information from all the units and elements, it is called census method.
• Sample Method : It is the method in which a small part of the population, i.e. some selected representatives units out of all the units are selected.
• Ideal Sampling : When the investigator selects samples on the basis of his intelligence and experience, then it is known as ideal sampling.