Samples of size 16 and 14 were taken from the population of

Samples of size 16 and 14 were taken from the population of ETSU men and women respectively. The mean ages of the men and the women were 23.4 and 21.8 respectively, and the sample SDs were 2 years for men and 3 years for women. Find a 90% confidence interval for mu_1 - mu_2, CAREFULLY stating your assumptions. Test the null hypothesis that mu_1 - mu_2 equals zero against the alternative that it is not zero. Use alpha =0.05.

Solution

11) Since sample size is samll, we use t distirbution. Excel is used for calculating Ci

(0.0348,3.1652)

12) excel is used for the analysis

p >0.05, hence H0 is accepted.

Hypothesis Test: Independent Groups (t-test, pooled variance)
	labe 1	label 2
	23.4	21.8	mean
	2	3	std. dev.
	16	14	n
		28	df
		1.6000	difference (labe 1 - label 2)
		6.3214	pooled variance
		2.5142	pooled std. dev.
		0.9201	standard error of difference
		0	hypothesized difference
		1.74	t
		.0930	p-value (two-tailed)