It was discovered that a larger proportion of children who slept with nightlights later developed nearsightedness, compared to children who did not sleep with nightlights.The headlines read, "Leaving a light on for you children causes nearsightedness!" Later it was pointed out that nearsighted people have more trouble seeing in the dark and are more likely to leave lights on at night for their kids.And those same nearsighted parents are likely to have nearsighted kids.This is an example of
A)a randomized block design.
B)a control group.
C)bias.
D)a placebo.
E)a lurking variable.

Question

Quizplus · Accepted Answer

This scenario illustrates a lurking variable, which is an unobserved variable that influences the association between the variables of interest (in this case, the use of nightlights and the development of nearsightedness). The genetic predisposition for nearsightedness, passed from parents to children, is the lurking variable that explains the observed association.

It Was Discovered That a Larger Proportion of Children Who