Question

A group of scientists are researching a possible relationship between dust mite infestations and seasonal allergies. What type of variable is a dust mite infestation? A. Qualitative B. Independent C. Dependent D. Nominal

Answer 1

Here dust mite infestation causes allergy. Hence we will collect data on both and try to understand what amount of dust mite will create what level of allergy.

So , here we want to predict at a given dust mite concentration what level of allergy will happen. That means dust mite infestation is the independent variable.

Also , dust mites are collected as numeric data with per mg or oer gram unit..hence not qualitative data. So , it can't be ordinal or nominal.