Dr Nguyen Is a Psychologist Who Studies Legal Decision Making

Dr. Nguyen is a psychologist who studies legal decision making. Specifically, he is curious about the factors that are irrelevant to the crime committed that influence the sentences juries give to defendants (known as extra-legal factors). To study this further, he samples a group of jury-eligible adults from the Memphis area. He provides them with the fact pattern to a particular case and allows them to watch the closing statements from the trial. He then asks them to provide a sentence (in months) for the defendant. In addition, he measures two legal factors (the number of arguments made by the prosecuting attorney and the length of time the defense attorney speaks during his or her closing argument) and two extra-legal factors (how attractive the participants think the defendant is [higher scores indicate higher ratings of attractiveness] and how many legal televisions shows the participants watch). The data are below.

Explain whether Dr. Nguyen could conduct an experiment instead of a multiple regression design. Regardless, why would an experiment be better than his current study?