Descriptive Statistics

NMeanStDevSE Mean95% CI for 25024.0684.6580.295(23.488, 24.648)

: population mean of Age of First Marriage, 2004

1.State the sample size, sample mean, and sample standard deviation.

n =

x

=

s

=

2.State the 95% confidence interval for m in 2004.

3.State the 95% confidence interval for m in 1994.

4.Notice that the confidence interval for 1994 is wider than that for 2004. That is, its

margin of error is greater. Which factor in the confidence interval computation

accounts for this greater margin of error? Indicate the one correct answer.

a.the sample mean

b.the sample standard deviation

c.the sample size

d.the za/2 value

5.Consider the relationship between the two confidence intervals you computed.

Do they suggest that we can be fairly confident that the population mean in 2004

is actually higher than it was in 1994? Or, is it more statistically sound to say that

we can't determine whether the average age at first marriage increased between

1994 and 2004? Explain, using a complete sentence or two.

6.State the P-value for your hypothesis test.