A study by Lefvre et al. (2010, PLoSONE 5: e9546) investigated whether alcohol consumption affected peoples' attractiveness to the mosquito, Anopheles gambiae, which is the primary vector of malaria in Africa.Data were collected on a total of 43 human participants, and each person was tested twice for attractiveness to mosquitos.In the first round, all participants were alcohol-free.Then, in the second round, participants were randomly assigned to drink either a liter of beer (participants) or a liter of water (), and the test was repeated 15 minutes after they had consumed their drink.

To estimate a person's attractiveness to A. gambiae, a vial of 50 mosquitos was released into the Y-tube apparatus shown in Figure 1.Participants were seated in a small tent, which was connected by an air hose to one of two mosquito traps.This allowed the mosquitos to detect and respond to olfactory cues from the participants, without exposing the participants to the mosquitos.The proportion of mosquitos that had flown toward the participant was recorded as the response variable.

State a research question for these analyses.Be sure to clearly identify (i) the sample unit, (ii) the response variable, and (iii) the explanatory variable (hint: the explanatory variable here is not the type of beverage!).

Sample unit is the change in people's attractiveness before and after drinking. Response variableis mosquitoes' response. Explanatory response could be alcohol content?

I am not sure about my variables and also I feel pretty lost on the format of research question since my prof did not give us an example in class. I don't know if I should include all the elements form i to iii in the question.