Effect of sample size on confidence intervals

Reference no: EM1395411

The National Assessment of Educational Progress (NAEP) sample of 1077 young women had mean quantitative score =275. Take it as known that the standard deviation of all individual scores is = 60.

1. Suppose that the same result, the mean quantitative score = 275, had come from a sample of 250 women. Give the 95% confidence interval for the population mean in this case.

2. Then suppose that a sample of 4000 women had produced the sample mean 275, and again give the 95% confidence interval for the population mean.

3. What can you say about the effect of sample size on confidence intervals?

Reference no: EM1395411

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