Question

A Bloomberg BusinessWeek subscriber study asked, "In the past 12 months, when traveling for business, what type of airline ticket did you purchase most often?" A second question asked if the type of airline ticket purchased most often was for domestic or international travel. Sample data obtained are shown in the following table. Type of Flight Type of Ticket Domestic International First Class 26 23 Business Class 96 129 Economy Class 513 134 a. Using a .05 level of significance, is the type of ticket purchased independent of the type of flight? Use Table 12.4. H 0: H a: Compute the value of the 2 test statistic (to 2 decimals). 1.84 The p-value is . What is your conclusion? b. Discuss any dependence that exists between the type of ticket and type of flight.

Answer 1

Ans:

	Observed freq(fo)
	Domestic	international	Total
First class	26	23	49
Business class	96	129	225
Economy class	513	134	647
Total=	635	286	921
	Expected freq.(fe)
	Domestic	international	Total
First class	33.78	15.22	49
Business class	155.13	69.87	225
Economy class	446.09	200.91	647
Total=	635	286	921
	Chi square=(fo-fe)^2/fe
	Domestic	international	Total
First class	1.79	3.98	5.78
Business class	22.54	50.04	72.58
Economy class	10.04	22.29	32.32
Total=	34.37	76.31	110.68

Test statistic:

Chi square score=110.68

df=(3-1)*(2-1)=2

p-value=CHIDIST(110.68,2)=0.0000

As,p-value<0.001,we reject the null hypothesis and we can conclude that there is significant dependence that exists between the type of ticket and type of flight.