(a) Give a brief outline describing how confidence intervals for means use the normal distribution or Student's t distribution in their basic construction.

BenoguigoliB 2020-11-17 Answered
(a) Give a brief outline describing how confidence intervals for means use the normal distribution or Student's t distribution in their basic construction.
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wornoutwomanC
Answered 2020-11-18 Author has 81 answers
The normal distribution is used for confidence interval in their basic construction when the population standard deviation (σ) is known.
Let x be a random variable. If it is assumed that x has a normal distribution, then any sample size will work. If it is not assumed that x has normal distribution, then the sample size should be greater 30.
For constructing confidence interval, sample mean (x), population standard deviation (σ), sample size n, and critical z value are used.
The confidence interval for means at a is as follows:
CI={x±za2σn}
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