Question

ap stats lessons 4.5 to 4.9
name
quiz

1. a study in malindi, kenya, was undertaken to determine if a relationship existed between the

water drainage and mosquito population in different areas of the city. using gps, the city was
overlaid with a map containing 50 grid cells. ten of the cells that contained standing water,
and ten of the cells with good water drainage were randomly selected and the mosquito
population was estimated for each cell. what type of study was conducted, and what is the
response variable?
a) an experiment was conducted, and the response variable is the drainage potential.
b) an experiment was conducted, and the response variable is the mosquito population.
c) a census was conducted, and the response variable is the association between drainage
potential and mosquito population.
d) an observational study was conducted, and the response variable is the drainage potential.
e) an observational study was conducted, and the response variable is the mosquito
population.

Explanation:

• Type of study: In an observational study, researchers observe and measure characteristics without manipulating variables. Here, the study just selected existing cells (with standing water or good drainage) and measured mosquito population. There was no manipulation of drainage (like changing it artificially), so it's an observational study. In an experiment, there would be some treatment (manipulation) applied. A census involves studying the entire population (all 50 grid - cells here, but only 20 were selected).
• Response variable: The response variable is what is being measured or observed as a result. The goal is to see how it relates to another variable. Here, the mosquito population is being measured to see its relationship with water drainage. So the mosquito population is the response variable.

Answer:

E. An observational study was conducted, and the response variable is the mosquito population.