BEYOND THE NUMBERS 1.5 Research Randomizer Name: To be graded, all assignments must be completed and submitted on the original book page. Background A simple random sample is the easiest kind of statistically viable sample to select and measure. But how do you actually select an SRS? One useful tool is the Research Randomizer, available at: http:// www.randomizer.org/. The following activities are designed to allow you to get familiar with this tool. EXHIBIT 1 No-Stumble Sampling Section Number: Data from the NHTSA's 1998 San Diego field sobriety test validation study is available at www.statconcepts. com/datasets. There are 296 participants in this study, so there are 296 case numbers displayed. Note, though, that these case numbers do not run sequentially from 1 to 296. Your job is to use Research Randomizer to select a sample of 20 cases from this data set. Questions 1. Explain how you plan to identify the cases for Research Randomizer 2. What entries did you use for the following Research Randomizer fields? TABLE 1.2 Research Randomizer Fields How many sets of numbers do you want to generate? How many numbers per set? Number Range (e.g., 1-50) Scanned with CamScanner Theme 1: Sampling 11 3. For the 20 cases selected, fill out the following chart: TABLE 1.3 Results for 20 Cases Case Number Actual BAC Case Number 4. What is the average BAC ("Blood Alcohol Content") of the 20 selected cases? EXHIBIT 2 Social Media Sampling Revisited 5. What proportion of cases in your sample had BACS at or above the legal limit of 0.04? A Actual BAC Suppose you have 113 friends on Facebook and you want to choose a simple random sample of 20 of them to ask a survey question you have constructed. Question 1. Carefully explain how you could use Research Randomizer to select your sample. follow like anddybear The wall friends CS Scanned