Sampling Designs Systematic Sampling Cluster Sampling Multistage Sampling

1. Sampling DesignsSystematic SamplingCluster SamplingMultistage Sampling

2. Pg 1.2 Name this sampling method.

3. Page 1.3 Name this sampling method

4. Page 1.4 Name this sampling method

5. Systematic Samplestart with a list of elements Choose a random starting point How do you decide how many to jump? Total  sample size then round off Jumped 3 Jumped 3 Jumped 3 Page 1.5 practice finding jump number - end

6. Systematic Sample Select a random starting place then jump every nth (3 or 4 or 5 etc ) elements to get next selection Systematic can give a representative sample if there is no connection between the order and the Pros Cons 1- Easy, don’t have to number the list 1- Real possibility of Bias if there is a connection that you don’t see. 2- less expensive than other methods. 2- Only good for medium size populations.

7. Cluster Sample

8. Cluster Sample Page 1.6 & 1.7 how many in cluster given a population

9. Cluster Sample When the population is broken up into smaller groups that are representative (mini me) of the population. You usually do a censes on a cluster. A cluster is a small group that has all the properties of the whole. Page 1.6 practice finding jump number - end

10. Multistage Sample Where you use multiple sampling methods; like doing a stratified then breaking each strata into clusters and doing a census on random clusters.

11. End Answer the questions on the back side of your notes, Don’t forget to answer the questions in the calculator also, start on page 2.1 to 2.4

13. Sometimes there are problems with a sample – these are called biases. Some are accidental and some not…

14. Types of Biases: Voluntary response I Will ! I Will ! I Will !

15. Types of Biases: I WONT’T I WONT’T Nonresponse REFUSED REFUSED

16. What is the difference between Voluntary and Nonresponse Biases?

17. Types of Biases: Undercoverage

18. Types of Biases: Response Should wolfs be allowed in Yellowstone park where families vacation? Should vicious, wild wolfs be allowed in Yellowstone park with vacationing families? or

20. Hoping to learn what issues may resonate with voters in the coming election, the campaign director for a mayoral candidate selects one block from each of the city’s election districts. Staff members go there and interview all the residents they can find. Identify the following as a team. Population b) population parameter Sampling frame d) the sample e) Sampling method f) potential biases

21. State police set up a roadblock to estimate the percentage of cars with up-to-date registration, insurance, and safety inspection stickers. They usually find problems with about 10% of the cars they stop. Identify the following as a team. Population b) population parameter Sampling frame d) the sample e) Sampling method f) potential biases

22. Dairy inspectors visit farms unannounced and take samples of the milk to test for contamination. If the milk is found to contain dirt, antibiotics, or other foreign matter, the milk will be destroyed and the farm reinspected until purity is restored. Identify the following. Population b) population parameter Sampling frame d) the sample e) Sampling method f) potential biases