Question

Max wants to start a farm to grow mussels. He needs to determine the best environment for growing them. He is going to try two different amounts of salt in the water (salinity) and three different water temperatures. For his experiment he has 18 aquariums, each with 20 mussels. He wants to see which environment produces the largest mussels.
1. Identify the subjects.
2. Identify the factors and levels.
3. Identify the treatments.
4. Identify the response variable.
5. Describe an advantage to random assignment of treatment.
6. Explain how replication would be used in this study.
7. Someone suggested that Max arrange the tanks so that six with the lowest temperature are on one end of the room, and the six with the highest temperature are at the other end of the room. Explain how this could introduce confounding into the experiment.
8. Would it make sense to have a control group that did not get any of the treatments described above?

Answer 1

Answer:

1.) Subject = 18  Aquariums each with mussel

2.) Factors(levels) = temperature(3 levels) and salinity (2 levels)

3.) Treatment = High salinity high temperature ; High salinity low temperature ; High Salinity medium temperature ; Low salinity Low temperature ; Low salinity, High temperature ; Low salinity Medium temperature.

4.) Response variable = size of mussel produced

5.) Random assignment will help prevent the introduction of bias and confounding variable.

6.) For replication purpose, Each of the six treatment could be assigned to 3 tanks, so 3 aquarium for one treatment.

7.) By doing such we might be a possible location based effect which might might creep into our research. Hence, causing a spurious relationship.

8.) A control experiment whereby no salt is added will cause the mussel to die as they require salt to survive.

Step-by-step explanation:

Answers are Explanatory.