1. A researcher wants to see the effects of mood and amount of sleep on concentration. Two groups of participants are allowed to sleep either 8 or 5 hours in a sleep lab. Within those groups, half are induced with a happy mood, and half are induced with a sad mood. Then they are asked to perform a demanding cognitive task and how well they are able to concentrate is recorded.

1. What type of research design is being used?

1. What is (are) the independent variable(s)? What are the levels?

1. What is the dependent variable?

2. A researcher wants to examine the differences between attachment in dogs and cats. A group of dogs and cats are used for the study. Each pet interacts with their owner for an hour while being videotaped. The number of times they seek attention from their owner is recorded.

1. What type of research design is being used?

1. What is (are) the independent variable(s)? What are the levels?

1. What is the dependent variable?

3. A researcher wants to measure the measure the urge to smoke. A group of participants watches a 30-minute intervention video. Another group watches a 30-minute video about nature. Both groups are given a survey, which measures their urge to smoke, before and after watching the video.

1. What type of research design is being used?

1. What is (are) the independent variable(s)? What are the levels?

1. What is the dependent variable?

4. A researcher wants to see the effects of a fatty diet on rat mobility. The researcher has 3 groups of rats. One group is fed standard rat chow; the second group is fed a high fast diet, and the third group is fed a medium fat diet. The weight gain of the rats is recorded.

1. What type of research design is being used?

1. What is (are) the independent variable(s)? What are the levels?

1. What is the dependent variable?

5. A researcher wants to study depression. He wants to measure the efficacy of 2 drugs in combination with the efficacy of 2 types of therapy.

1. What type of research design is being used?

1. What is (are) the independent variable(s)? What are the levels?

1. What is the dependent variable?

6. A researcher wants to study the effects of caffeine on attention. Design an experiment to test this. Include discussion of relevant variables including how they will be involved in the study and what data is being collected