A researcher noticed that, for streams along the East Coast, the amount of money spent on restoration and the number of distinct fish populations present appeared to have a negative correlation.
Which of the following statements is most likely to be the reasoning the researcher used to decide that a lurking variable must be present?

Question

Quizplus · Accepted Answer

The researcher likely used the reasoning that spending more money on restoration often indicates a greater need for restoration, which would suggest a stream of lower quality. If a stream is of lower quality, then there may be fewer fish populations present. This means that the negative correlation between money spent on restoration and fish populations may be due to a lurking variable, such as the overall health of the stream. Choice A is incorrect because correlations can indeed be negative. Choice B is incorrect because the researcher may have had no prior expectation for the direction of the correlation. Choice D is incorrect because there is a correct answer.

A Researcher Noticed That, for Streams Along the East Coast