Responding driven sampling Principles of Sampling Session 1
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- Slide 2
- Responding driven sampling Principles of Sampling Session
1
- Slide 3
- After this session, you should be able to Outline the purpose
of sampling Understand key theoretical concepts in sampling
Describe the concept of selection bias and random error in sampling
2WWW.HIVHUB.IR
- Slide 4
- Why do we sample? We sample when we desire to measure
characteristics of a specified population (e.g., the proportion of
the general population who have unsafe sex) but lack the time and
resources to obtain information from all members of the population.
Concentrating survey time and resources on a sample may also result
in better quality data than if resources were spread over the whole
population. 3WWW.HIVHUB.IR
- Slide 5
- Key definitions Sampling unit (element): Subject under
observation on which information is collected Example: adults
- Target population-> Study Population-> Sample
7WWW.HIVHUB.IR Target Population: All homeless in country X Study
Population: All homeless in capital shelters in the Sample:
Homeless at particular shelter