Question

Is the transportation mode used to ship goods independent of type of industry? Suppose the following contingency table represents frequency counts of types of transportation used by the publishing and the computer hardware industries. Analyze the data by using the chi-square test of independence to determine whether type of industry is independent of transportation mode. Let = 0.05. Transportation Mode Industry Air Train Truck Publishing 34 12 38 Computer Hardware 5 6 24 Appendix A Statistical Tables (Round the intermediate values to 2 decimal places. Round your answer to 2 decimal places.) Observed X squared =

Answer 1

Applying chi square test of independence:

Observed		Air	train	Truck	Total
	Publishing	34	12	38	84
	Computer Harfware	5	6	24	35
	total	39	18	62	119
Expected	Ei=row total*column total/grand total	Air	train	Truck	Total
	Publishing	27.53	12.71	43.76	84
	Computer Harfware	11.47	5.29	18.24	35
	total	39	18	62	119
chi square    χ2	=(Oi-Ei)2/Ei	Air	train	Truck	Total
	Publishing	1.52	0.04	0.76	2.3200
	Computer Harfware	3.65	0.10	1.82	5.5700
	total	5.1700	0.1400	2.5800	7.8900
test statistic X2=		7.89