Refer to Example 13.8.1. Another variable of interest to Lacroix et al. (A-7) was the number of alveolar cells in three groups of subjects exposed to air, benzaldehyde, or acetaldehyde. The following table gives the information for six guinea pigs in each of the three treatment groups.

Number of Alveolar Cells ð106

Þ

Air Benzaldehyde Acetaldehyde 0.55 0.81 0.65 0.48 0.56 13.69 7.8 1.11 17.11 8.72 0.74 7.43 0.65 0.77 5.48 1.51 0.83 0.99 0.55 0.81 0.65 Source: Data provided courtesy of G. Lacroix.

May we conclude, on the basis of these data, that the number of alveolar cells in ovalbumin-sensitized guinea pigs differs with type of exposure? Let a ¼ :05.