Must the variable under consideration be normally distributed for you to use the z-interval procedure or t-interval procedure? Explain your answer.

Short Answer

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No.

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01

Explanation

No,

The z-interval or t-interval approach can be used to find the confidence interval of a population mean even if the variable under investigation is not normally distributed.

Because of the following conditions are met, we can apply the z-interval or t-interval technique for non-normally distributed variables.

  • Large sample i.e, sample size >30
  • The variable in question is near to being normally distributed, and there are no outliers in the sample data.

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