Warm Up A 2017 report from the National Student Clearinghouse Research Center measured the percentage of students who had graduated, were still enrolled or had dropped out of college 6 years after their initial enrollment. Graduated Still Enrolled Dropped Out Asian 63% 17% 20% Black 38% 17% 45% Hispanic 46% 19% 35% White 62% 11% 27% Use this information to make a segmented bar graph.

Two-Way Tables – Marginal Distribution A 2002 study by the Gallup poll examined the perceived risk of smoking among smokers and non-smokers. The study included 241 smokers and 502 non-smokers. Risk: Smokers Non-Smokers Very harmful 145 432 Somewhat harmful 72 50 Not too harmful 17 15 Not at all harmful 7 5 What percentage of the individuals in the study believe that smoking is very harmful? 2) What percentage of the individuals in the study believe that smoking is not at all harmful?

Two-Way Tables – Conditional Distribution A 2002 study by the Gallup poll examined the perceived risk of smoking among smokers and non-smokers. The study included 241 smokers and 502 non-smokers. Risk: Smokers Non-Smokers Very harmful 145 432 Somewhat harmful 72 50 Not too harmful 17 15 Not at all harmful 7 5 Is the perceived risk of smoking different for smokers vs. non-smokers? Describe any significant differences and similarities between the 2 groups.

Practice The Princeton Review in 2009 published survey results of 12,715 high school students and 3007 parents of high school students. One question that was asked: “How far from home would you like the college your child attends to be?” Students Parents < 250 miles 4450 1594 250 – 500 miles 3942 902 500 – 1000 miles 2416 331 > 1000 miles 1907 180 Describe any significant differences or similarities between the distance from home students and parents would like their college to be.

Simpson’s Paradox In 1973 UC – Berkeley was sued for sex discrimination. The data on admission rates to graduate school (in percent) looked pretty convincing. Men Women Accepted 44 35 Denied 56 65 Ultimately UC – Berkeley won the case. Any thoughts on why?

Simpson’s Paradox – Effect of a Third Variable When we consider a third variable, which programs students applied to, the results change. Men applied more often to science and engineering programs, which have a relatively high acceptance rate. Women applied more to humanities and liberal arts, which have fewer openings. Men Women Science and Engineering Accepted 377 (49%) 85 (80%) Denied 399 (51%) 21 (20%) Humanities Accepted 51 (26%) 92 (23%) Denied 145 (74%) 308 (77%)