SOAN 3120 Chapter Notes - Chapter 8: Simple Random Sample, Response Bias, Call Screening
22 Oct 2016
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Document Summary
The population in a statistical study is the entire group of individuals about which we want information: time, cost, and inconvenience preclude contacting each individual. A sample is part of the population from which we actually collect information: we use a sample to draw conclusions about the entire population. A sampling design describes exactly how to choose a sample from the population. The first step in planning a sample survey is to say exactly what population you want to describe. The second step is to say exactly what you want to measure. A sampling design is a specific method for choosing a sample from the population. Convenience sample: a sampled selected by taking the members of the population that are easiest to reach: not necessarily the best, often produce unrepresentative data, creates a systemic error. The design of a statistical study is biased if it systematically favours certain outcomes.
