Sampling distribution 6 for n 25 38 x 3 x find z

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Unformatted text preview: ample means would be between 362.12 and 373.88 grams. σ Known Example Find an interval symmetrically distributed around the population mean that includes 95% of the sample means. Sampling distribution: µ= 6; σ = for n = 25 38 x 3 x find z-scores for 2.5% and 97.5%: z = ±1.96 2.5% find corresponding sample means: − z = xσ µ x x lower tail : upper tail : Interval Estimation −1.96 = x −µ 3 −5.88 = x − µ 1.96 = x −µ 3 5.88 = x − µ sampling error—difference between sample mean and population mean xL 95% xU -1.96 μ 1.96 2.5% σ Known Example Find an interval symmetrically distributed around the population mean that includes 95% of the sample means. Sampling distribution: µ= 6; σ = for n = 25 38 x 3 x find z-scores for 2.5% and 97.5%: z = ±1.96 2.5% find corresponding sample means: x ± 5.88 − z = xσ µ x x lower tail : upper tail : Interval Estimation −1.96 = x −µ 3 −5.88 = x − µ If sample mean is known, use to find a range for the population mean: x ± 5.88 1.96 = x −µ 3 5.88 = x − µ sampling error—difference between sample mean and population mean xL 95% xU -1.96 μ 1.96 2.5% σ Known Example Find an interval symmetrically distributed around the population mean that includes 95% of the sample means. Sampling distribution: µ= 6; σ = for n = 25 38 x 3 x find z-scores for 2.5% and 97.5%: z = ±1.96 2.5% find corresponding sample means: − z = xσ µ x x lower tail : upper tail : Interval Estimation −1.96 = x −µ 3 −5.88 = x − µ If sample mean is known, use to find a range for the population mean: x ± 5.88 xL 95% xU 2.5% -1.96 μ 1.96 1.96 = x −µ 3 5.88 = x − µ sampling error—difference between sample mean and population mean 5.88 is the margin of error σ Known Example Find an interval symmetrically distributed around the population mean that includes 95% of the sample means. Sampling distribution: µ= 6; σ = for n = 25 38 x 3 x find z-scores for 2.5% and 97.5%: z = ±1.96 find corresponding sample means: − z = xσ µ x x lower tail : upper tail : Interval Estimation −1.96 = x −µ 3 −5.88 = x...
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This document was uploaded on 03/05/2014.

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