1

The next step in the multiple comparison procedure is to compute a critical value for each pairwise comparison. The critical value for the if pairwise difference for k populations follows where ,'(R2 is the chi-square value with level of significance or and k 1 degrees of freedom for k populations, 5,: and 51. are the sample proportions for populations r' and j, and n}. and n]. are the sample sizes from populations i' and j. _ 32 ,.-'p-(l-p-} CV5}. \\ X\" f I The value for 1N2 will be used for all comparisons. Note that a will represent the upper tail area of the chi-square distribution. The desired level of signicance was given to be 0.05, so a = \\:| . There are three populations being compared, giving k = \\:| . Population 1 had 132 Yes responses and 118 No responses. Therefore, r11 = 132 + 118 = \\:|. Population 2 had 132 Yes responses and 168 No responses. Therefore, n2 = 132 + 168 = \\:|. Population 3 had 7'8 Yes responses and 122 No responses. Therefore, :13 2 T8 + 122 = \\:|. You may need to use the appropriate appendix table or technology to answer this question. Suppose that you are responsible for making arrangements for a business convention and that you have been charged with choosing a city for the convention that has the least expensive hotel rooms. You have narrowed your choices to Atlanta and Houston. The file named Hotel contains samples of prices for rooms in Atlanta and Houston that are consistent with a SmartMoney survey conducted by Smith Travel Research. Because considerable historical data on the prices of rooms in both cities are available, the population standard deviations for the prices can be assumed to be $20 in Atlanta and $25 in Houston. Based on the sample data, can you conclude that the mean price of a hotel room in Atlanta is lower than one in Houston? State the hypotheses. (Let u, = mean hotel price in Atlanta and let #2 = mean hotel price in Houston.) O Ho: H1 - H2 =0 Hi Hi - H2 = 0 H:H - 12 20 Hi Hi - H2