Bacteria in Hospital Carpeting Researchers wanted to determine if carpeted rooms contained more bacteria than uncarpeted rooms. To determine the amount of bacteria in a room, researchers pumped the air from the room over a Petri dish at the rate of 1 cubic foot per minute for eight carpeted rooms and eight uncarpeted rooms. Colonies of bacteria were allowed to form in the 16 Petri dishes. The results are presented in the table. A normal probability plot and boxplot indicate that the data are approximately normally distributed with no outliers. Do carpeted rooms have more bacteria than uncarpeted rooms at the = 0.05 level of significance?
Step 1 of 5) Bacteria in Hospital Carpeting Researchers wanted to determine if carpeted rooms contained more bacteria than uncarpeted rooms. To determine the amount of bacteria in a room, researchers pumped the air from the room over a Petri dish at the rate of 1 cubic foot per minute for eight carpeted rooms and eight uncarpeted rooms. Colonies of bacteria were allowed to form in the 16 Petri dishes. The results are presented in the table. A normal probability plot and boxplot indicate that the data are approximately normally distributed with no outliers. Do carpeted rooms have more bacteria than uncarpeted rooms at the = 0.05 level of significance Some Cautions Regarding Tukey’s Test Sometimes the results of Tukey’s test are ambiguous. Suppose the null hypothesis H0: m1 = m2 = m3 = m4 is rejected and the results of Tukey’s test indicate the following: m1 m2 m3 m4 It appears that populations 1, 2, and 3 have a population mean that is different from that of populations 3 and 4. Clearly, this is impossible. Do you see why
