Question

2. Turnover rates in the US and Japan. High job turnover rates are often associated with high product defect rates. In a recent study 5 Japanese and 5 US plants that manufacture air conditioners were randomly sampled; their turnover rates are listed in the table (10 pts)

US Plants (%)	Japanese Plants (%)		t-Test: Two-Sample Assuming Equal Variances	US Plants	Japanese Plants
7.11	3.52
6.06	2.02		Mean	6.562	3.118
8	4.91		Variance	1.482	1.506
6.87	3.22		Observations	5	5
4.77	1.92		Pooled Variance(sp2)	1.494	?
			Hypothesized Mean Difference	0
			Df	?	?
			t Stat	?	?
			P(T<=t) one-tail	0.001	?
			t Critical one-tail	?	?
			P(T<=t) two-tail	0.002	?
			t Critical two-tail	?	?

A.  Use the Excel output above to describe the two samples involved in the comparison:

Mean turnover rate in the US = ₁ =                               

                                         

                                        Japan  = ₂=

Pooled Variance (s_p²)=

Combined degrees of freedom (df): (show calculation)

B. Set up the null and alternate hypothesis in terms of the Mean difference (m₁-m₂)to test the hypothesis that turnover rates in the US plants exceedsthe turnover rates in Japanese plants.

C. Refer to the Excel output and calculate the test-statistic value (using the pooled variance provided)

D. The correct criticalt-valueata= 0.05 based on your hypothesis above is: (show the critical value(s) on a graph)

5. From the information provided above should you reject or accept the H₀?

6. What is the p-value? Using the p-value show whether we should accept or reject H­₀at a= 0.05.

7. Does the data provide sufficient evidence at the 5% level to suggest that the average turnover rates in US plants exceed that of Japanese plants? Explain.

Answer 1