population and sampling

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POPULATION & SAMPLING BY: DIVINE C BUNGAY

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is the act, process, or technique of selecting a suitable sample, or a representative part of a population for the purpose of determining parameters or characteristics of the whole population. the process of selecting a group of people, events, behaviors, or other elements with which to conduct a study. What is Sampling?

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Sampling frame list of all the elements in the population from which the sample is drawn. Could be extremely large if population is national or international in nature Frame is needed so that everyone in the population is identified so they will have an equal opportunity for selection as a subject (element) Continuation of What is Sampling?

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What is the purpose of sampling ? To draw conclusions about populations from samples, we must use inferential statistics which enables us to determine a population`s characteristics by directly observing only a portion (or sample) of the population. Continuation of What is Sampling?

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SAMPLES & POPULATION What is a sample ? A sample is a finite part of a statistical population whose properties are studied to gain information about the whole(Webster, 1985). When dealing with people, it can be defined as a set of respondents(people) selected from a larger population for the purpose of a survey. What is population ? A complete set of elements (persons or objects) that possess some common characteristic defined by the sampling criteria established by the researcher

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The Relationship Between a Population and a Sample Continuation of Samples & population

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Target vs Accessible Population Target population (universe) The entire group of people or objects to which the researcher wishes to generalize the study findings Meet set of criteria of interest to researcher Accessible population The portion of the population to which the researcher has reasonable access; may be a subset of the target population May be limited to region, state, city, county, or institution

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Continuation of Target vs Accessible Population Target population Examples : All institutionalized elderly with Alzheimer ' s All people with AIDS All low birth weight infants Accessible population Examples : All institutionalized elderly with Alzheimer's in St. Louis county nursing homes All people with AIDS in the metropolitan St. Louis area All low birth weight infants admitted to the neonatal ICUs in St. Louis city & county

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The Relationship Among the Target Population, the Accessible Population, and the Sample

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GOOD DAY!!!!