Question

A city in California has asked Professor Rodriguez to conduct an experiment on earthquake preparedness. Professor Rodriguez will assess the preparedness of a random sample of residents in the city and the city will mail out their annual brochure on earthquake safety. Then, two weeks later, he will again assess the preparedness of those residents. Right after the brochures are mailed, a large earthquake is reported in Japan. What threat to internal validity does this pose?

Answer 1

Answer:

history

Explanation:

In this context, history refers to some sort of change in the research environment that can influence the conclusion of the study.

Japan is a country that is known to have frequent amount of earthquake (to the point where almost all buildings in japan were made to be 'earthquake proof'. Due to this historical characteristics, almost all individuals in japan are prepared for earthquake, so the brochures would not really mean anything.