A study of 218 students at Ohio State University suggests a link between time spent on the social networking site Facebook and grade point average. Students who rarely or never used Facebook had higher grade point averages than students who use Facebook.
Source: Data extracted from M. B. Marklein, "Facebook Use Linked to Less Textbook Time," www.usatoday.com, April 14, 2009.
a. Does the study suggest that time spent on Facebook and grade point average are positively correlated or negatively correlated?
b. Do you think that there might be a cause-and-effect relationship between time spent on Facebook and grade point average? Explain.