Refer to the American Journal of Infection Control (Aug. 2014) study of the hygiene of hand greetings, Exercise 9.24 (p. 451). The number of bacteria transferred from a gloved hand dipped into a culture of bacteria to a second gloved hand contacted by either a handshake, high five, or fist bump was recorded. Recall that the experiment was replicated five times for each contact method and the data used to compare the mean percentage of bacteria transferred for any two contact methods. The data are repeated in the table.

a. What assumption about the variability of the data is required to make the mean comparisons for this small-sample study?
b. Conduct a test to determine if the assumption, part a, is reasonably satisfied when comparing the handshake to the fist bump. Test using a = .05.
c. How does your answer, part b, affect the validity of the inferences made in Exercise 9.24?

Transcribed Image Text:

Handshake: 131 44 70 92 53 21 129 74 69 96 43 High five: Fist bump: 15 14 21 29