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Explain why the margin of error determines the accuracy with which a sample mean estimates a population mean.

Short Answer

Expert verified

If the margin of error is small, population mean is estimated using x¯and precision of estimate is high.

Step by step solution

01

Given Information

Confidence level is 100(1-α)%

Sample mean is x—

Population mean is μ

Margin of error isE

02

Explanation

As margin of error is equal to the half of the length of the confidence interval. x-is the midpoint of the confidence interval.

With particular level of confidence 100(1-α)%, x-is deviated from μby Eunits.

The maximum possible error is E(margin of error).

Hence, if the margin of error is small, population mean is estimated using x-results in high precision.

This is how the margin of error determines the precision with which sample mean estimates a population mean.

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Most popular questions from this chapter

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