1. Explain the difference between a completely randomized experimental design and a randomized block design. Give an example of each. Why is a block design a better choice sometimes?

MUST be included:

• Definitions for each type of experimental design.
• An example of each type.
• A rationale for why randomized block design would be chosen over completely randomized.
• Show ALL work!
• Make sure your file/image is clear (not blurry) and easy to read.

2. A study was conducted that showed strong positive correlation between eating strawberries and the number of freckles on a person's face. Can we say that eating strawberries causes freckles? Explain.

Hint: Think about what causes freckles to be more visible.

Name a lurking variable for this situation.

3. A botanist is studying a newly identified mushroom disease. The botanist collected soil samples from randomly selected fields in each state to see if there were significant differences the mineral levels in fields with and without the disease.

1. What is the population? (all US botanists /all US diseases /all US soil/ all US mushroom fields)
2. What is the sample? (selected US botanists/ selected US diseases/ selected US soil/ selected US mushroom fields)
3. What is the variable of interest? (Number of mushroom fields/ number of mushrooms/ Percent of fields with disease/ Number of states affected/ Mineral levels in mushroom fields)
4. How was the sample selected? (Census/ Cluster sampling/ Convenience sampling/ Simple random sampling/ Stratified sampling)
5. What method was used to collect the data? (Experiment/ Observational study/ Simulation/ Survey)
6. Is the variable qualitative or quantitative? (qualitative or quantitative)
7. Is the variable continuous or discrete? (continuous or discrete)

4. A new restaurant has been open for three months and wants feedback from its customers. They plan to give a survey to every 5th customer.

Census or Sampling method: (Census/ Cluster sampling/ Systematic sampling/ Simple random sampling/ Stratified sampling)

Collection method: (Experiment/ Observational study/ Simulation/ Survey)

5. A dog food claims to make dogs coats shiner and healthier looking. A researcher wants to test the claims. They plan to randomly select pet store shoppers to participate and assign them to two groups.

Census or Sampling method: (Census/ Cluster sampling/ Convenience sampling/ Simple random sampling/ Stratified sampling)

Collection method: (Experiment/ Observational study/ Simulation/ Survey)

6. The Department of Homeland Security wants to test a computer virus that it has developed to combat hackers. They plan to test run the virus on randomly selected computers with pre-set "hacker" programs.

Census or Sampling method: (Census/ Cluster sampling/ Convenience sampling/ Simple random sampling/ Stratified sampling)

Collection method: (Experiment/ Observational study/ Simulation/ Survey)

7. The mean, median, and mode can be found for (qualitative or quantitative) data. Only the (mean/ median/ mode) can be found for (qualitative or quantitative) data.

8. A researcher numbers each household in the city and uses a random number generator to select individual households for the sample. By chance, none of the households chosen were households of single millennials. This is an example of (voluntary response bias/ sponsorship bias/ sampling error/ under coverage bias) ?

9. A company's receipts gives a website where customers can fill out a survey to receive a coupon. This is an example of (sampling error/ under coverage bias/ sponsorship bias/ voluntary response bias)?

10. Your friend forgot she was supposed to conduct a poll of your high schools' students. She asks everyone in your homeroom if they think the school should have a new mascot. She presents the results to the student council. This is an example of (sampling error/ sponsorship bias/ under coverage bias/ voluntary response bias)?

11. Use the random number table and the situation given to select a sample.

46795 05947 01934

89640 39437 90044

There are 88 students at the dance studio and 10 of them will be selected at random for cleaning duty every week. Each dance student receives a number from 01 to 88. The studio uses the above random digit table to pick the 10 students. We will have randomly pulled the numbers so we will start with the first number in the list for our first entry. From this random number table we arrive at the following students who will be used for our random sample.

46, Answer, Answer, Answer, Answer, Answer, Answer, Answer, Answer, Answer

12. Use the following data set to find the sample statistics for the following data set. (Round answers to the nearest hundredth, if necessary.

{51, 48, 42, 43, 48, 48 ,46, 15, 29, 45, 47, 55, 46, 35, 47, 48, 54, 26, 53, 42}

1. (N or n) = Answer?
2. (x bar or ) = Answer?
3. Median = Answer?
4. Mode = Answer?