Strayer and colleagues wanted to establish if there was a causal relationship between cell phone use while driving, traffic density, and increased risk of vehicular collision. They found evidence of an interaction because
A)cell phone use led to an increase in braking reaction time in both the low and high traffic conditions
B)cell phone use led to an increase in braking reaction time in the low traffic density condition
C)cell phone use led to an increase in braking reaction time only in the high traffic density condition
D)cell phone use did not affect reaction time in regardless of traffic density

Question

Quizplus · Accepted Answer

An interaction implies that the effect of one variable (cell phone use) on another variable (braking reaction time) changes depending on a third variable (traffic density). Choice A indicates that cell phone use increased braking reaction time in both low and high traffic conditions, suggesting an interaction between cell phone use and traffic density on braking reaction time.

Strayer and Colleagues Wanted to Establish If There Was a Causal