Option	Concept Task
1.	Researchers found that people who used candy cigarettes as children were more likely to become smokers as adults, compared to people who did not use candy cigarettes as children. a) Identify the explanatory variable and identify the response variable. b) Based on the short description above, do you think the findings were a result of an Observational Study or a Designed Experiment? Explain your thinking. c) When explaining this study to one of my classes,, a student of mine said: "But isn't the smoking status of the person's parents a confounding variable here?" Describe what it means for smoking status to be a confounding variable that provides an alternative to drawing a cause-and-effect explanation in this context.
2.	a) The county supervisor of Orange County with over 3 million adults wants to know what percentage of adults in the county currently have Covid-19 antibodies in their systems (blood). Of the following methods, and considering each participant will receive a $100 Amazon gift card for participating, which is the most appropriate way to collect samples? (i) Conduct a census by testing the blood of every adult in the county. (ii) Place a notice on social media platforms asking adults to volunteer to have their blood tested. (iii) Select a random sample of adults with KAISER health insurance and ask each if they would have their blood tested. (iv) Select a random sample of adults using cell phone and home phone records and ask each if they would have their blood tested. b) With the context from above in mind, explain which sampling method would be best, a Stratified Method using cities as the strata, or a Cluster Method using age groups (18-24, 25-29, ...) as the clusters?
3.	Consider full-time community college students as an observational unit. a) Come up with one categorical and one quantitative variable related to a full-time community college student. [You CANNOT use AGE, HEIGHT, GENDER, MAJOR]. b) Considering your categorical variable from part a), name three types of graphical displays you can use to represent that variable. c) Come up with one quantitative variable for a community college student that would have a distribution that is SKEWED RIGHT or SKEWED LEFT.