Probability sampling uses random selection as the method of sampling. You must set up random selection that will allow all units of having the same amount of probability of being
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Imagine how difficult and costly it would be for a company to survey everyone in the United States every time it wants to know something about Americans. If a sample is created randomly
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is a branch of mathematics thatb deals with money.
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A probability sample is a sample where every element of the target population has a known, nonzero probability of being selected. That is, it is possible for every element of the
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