A variable of a population has a normal distribution. Suppose that you want to find a confidence interval for the population mean. a. If you know the population standard deviation, which procedure would you use? b. If you do not know the population standard deviation, which procedure would you use?

Lokubovumn

Lokubovumn

Answered question

2022-08-09

A variable of a population has a normal distribution. Suppose that you want to find a confidence interval for the population mean.
a. If you know the population standard deviation, which procedure would you use?
b. If you do not know the population standard deviation, which procedure would you use?

Answer & Explanation

Ayla Coffey

Ayla Coffey

Beginner2022-08-10Added 8 answers

a) Following assumptions are required for the large sample confidence interval about mean to be valid.
Requirements for a large sample confidence interval about mean:
The sample must be drawn using simple random sampling.
The population standard deviation must be known.
Either the population must be approximately normal or the sample size must be greater than 30.
Thus, the requirements must be satisfied for the confidence interval about mean using standard normal distribution to be valid.
Here, the population standard deviation is known.
Thus, the one-mean z-interval procedure can be used to construct confidence interval about mean in case of known population standard deviation.
b. Following assumptions are required for the small sample confidence interval about mean to be valid.
Requirements for a small sample confidence interval about mean:
The sample must be drawn using simple random sampling.
The population standard deviation must be unknown.
Either the population must be approximately normal or the sample size must be greater than 30.
Thus, the requirements must be satisfied for the confidence interval about mean using t-distribution to be valid.
Here, the population standard deviation is unknown.
Thus, the one-mean t-interval procedure can be used to construct confidence interval about mean in case of unknown population standard deviation.

Do you have a similar question?

Recalculate according to your conditions!

New Questions in College Statistics

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?