WS: Sampling Distributions Names:
Case Study 1: National Youth Tobacco Study
The National Youth Tobacco Survey (NYTS) is a complex survey carried out by the CDC to better un-
derstand the rate of e-cigarette usage among teens. It is a school-based, pencil-and-paper questionnaire,
self-administered to a nationally representative sample of students in grades 6-12 in the U.S. In 2019, 5,675
students completed the NYTS; the overall survey response rate was 71.6%. Among other questions, stu-
dents were asked if they had used an e-cigarette in the past 30 days.
1. Describe the sample. How large is it (𝑛) and what is the unit of observation?
2. Describe the population. Approximately how large is it (𝑁)?
3. Select a population parameter that researchers would be interested in estimating and the correspond-
ing statistic that will serve as the estimate.
4. Identify possible sources of statistical bias and whether they are selection, measurement, and non-
response bias. How do you expect this will effect the estimate of the parameter?
5. Identify possible sources of variation and whether they are sampling or measurement variability. How
do you expect this will effect the estimate of the parameter?
Stat 20 Summer 2025
