D. Sampling Distributions

• Distribution of a sample statistic if all possible samples could be taken

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• Allows conclusion about population parameter to be drawn from sample statistic

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1. Sampling distribution of the sample mean

• Distribution of all possible sample means if all possible samples of a given size are selected

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a. Unbiased property of the sample mean

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b. Standard error of the sample mean

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c. Sampling from normally distributed populations

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Ex. -

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d. Sampling from nonnormally distributed populations

• Central Limit Theorem - if the sample size is large (n>= 30), the sampling distribution of the mean can be approximated by the normal distribution, regardless of the distribution of the population

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Ex. -

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2. Sampling distribution of the sample proportion

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Ex. -

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