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Does the sample size have an effect on the standard deviation of all possible sample means? Explain your answer.

Short Answer

Expert verified

Yes, the sample size has an effect on the standard deviation of all possible sample means.

Step by step solution

01

Step 1. Given Information

We need to identify whether the sample size has an effect on the standard deviation of all possible sample means.

02

Step 2. Explanation

For samples of size n,the standard deviation of the variable x¯equals the standard deviation of the variable under consideration divided by the square root of the sample size. That is, σx¯=σn.

So, it can be seen that the standard deviation of all possible sample means depends on the sample size n.

And it can be seen that as the sample size increase the standard deviation ofx¯decreases.

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Most popular questions from this chapter

According to the central limit theorem, for a relatively large sample size, the variable x~is approximately normally distributed.

a. What rule of thumb is used for deciding whether the sample size is relatively large?

b. Roughly speaking, what property of the distribution of the variable under consideration determines how large the sample size must be for a normal distribution to provide an adequate approximation to the distribution of x~ ?

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7.2 Why should you generally expect some error when estimating a parameter (e.g., a population mean) by a statistic (e.g., a sample mean)? What is this kind of error called?

Why is obtaining the mean and standard deviation of x¯ a first step in approximating the sample distribution of the sample mean by a normal distribution?

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