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Sampling in Statistics I
Sampling
When one by one study of all units of a population is not possible due to some factors like time, cost, manpower, resources and destructive nature of study, we take a small representative part from the population for the study. This small representation part selected for the study from the population is called sample. The process of selecting a sample from a population is called sampling.
For example :- A pathologist takes a syringe of blood as a sample to find out a disease.
Merits of Sample Survey
- It is less expensive.
- It requires less time to get result.
- It need smaller number of resources.
- It is the only method for large population.
Demerits of Sample Survey
- It is not suitable method if information about all units of population is required.
- It is not suitable for rare events.
- It is not suitable for historic data.
Basics Steps in Sampling
- Objective of the survey
- Defining population to be sampled
- Data to be collected
- Degree of precision desired
- Methods of measurement
- Frame
- Selection of proper sampling design
- Organization of field work
- Summary and Analysis of data
