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Estimations, Confidence intervals, Sample Size

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Why are estimations and confidence intervals important?

Do confidence intervals and estimation play a role in the selection of sample size?

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Solution Summary

The expert determines why estimations and confidence intervals are important. Whether confidence intervals and estimation plays a role in the selection of sample size is determined. A complete, neat and step-by-step solution is provided in the attached file.

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Estimations are inferential tools that are used when we know there is an effect (or we found an effect) and we wish to figure out the size of the effect (quantify the effect) in an unknown population.
Since the parameters of a population are generally unknown (unless a census is taken- which is impractical in most situations), or we may not have all the information that we may need, estimating a population parameter using a sample statistic is the only way out.
Confidence intervals are required to qualify our estimation. Confidence intervals are one way to represent how "good" an estimate is; the larger a ...

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