Sean is a transportation engineer and is interested in whether roadways that score high in one traffic engineering aspect also tend to score high in other aspects. To address this question, he completed a survey of 80 roadways that contain five measures of effectiveness with ratings for safety, capacity, speed, alignment and flow.
Conduct a correlational analysis to investigate these relationships. What are your conclusions?
Sean determines that the speed of a facility impacts the other roadway scores. Reevaluate Sean's hypothesis by controlling for speed. What effect does partialling out the effects of speed have on the relationships?