1. Sampling Methods Determine what type of sampling method is being used for each of the following

2. #1 A company breaks its workers into 6 divisions, then chooses one of the divisions and surveys every person in that division

3. #1 ANSWER Cluster Sample We divided the population into groups, chose ONLY ONE of the groups and surveyed EVERY person in that group

4. #2 The airport security randomly checks every seventh bag that comes through the conveyor belt

5. #2 ANSWER Systematic Sample Choosing every nth bag makes this a systematic sample

6. #3 Mr. Puccio and Ms. Squiccimarri take a random survey of 15 boys and 15 girls from each of the four grades in our school

7. #3 ANSWER Stratified Sample The population was divided into four groups, ALL of the groups were selected and ONLY 15 people were chosen from each group

8. #4 Mr. Lynch wants to choose 6 students to make class presentations in class tomorrow. He writes each person’s name on a slip of paper and has Mr. Demaio pull 6 names from the pile

9. #4 ANSWER SRS (Simple Random Sample) Each member of the population has an equally likely chance of being selected

10. #5 To gather a quick sample, Mr. Lynch asks each student in his 1 st period class how many text messages they send on a daily basis

11. #5 ANSWER Convenience Sample Lynch asks the first group of students he sees Cluster Sample The population of students Lynch teaches is divided into 5 groups (He teaches 5 classes). He then picked one class and surveyed everybody in that class

12. #6 Because of the recent issues with their brakes, Toyota decides to check the breaks of every eighth vehicle that comes off of the assembly line

13. #6 ANSWER Systematic Sample Sampling every 8 th car makes this a systematic sample

14. #7 Instead of checking the breaks for every eighth vehicle like Toyota does, Chevrolet decides to check the breaks in every Chevy Traverse that comes off the assembly line

15. #7 ANSWER Cluster Sample The population is divided into groups (each model vehicle). One group was selected (Traverse) and all vehicles in this group were selected

16. #8 To find out what students think of the college cafeteria, workers go to each dorm building, pick two random dorm rooms, and survey every student in those rooms

17. #8 ANSWER This is a stratified sample followed by a cluster sample This starts as stratified because the worker is going to every building and surveying some of the rooms. It becomes a cluster sample because the worker picked some of the rooms in the dorm and surveyed every person in those rooms

18. #9 To see how the general public is responding to Healthcare reform, a computer produces 10,000 phone numbers from throughout the country and telemarketers call to ask the head of the household for an opinion

19. #9 ANSWER SRS (Simple Random Sample) Each member of the population has an equally likely chance of being selected and in this case a random number generator was used to choose the sample