Question

An experiment was done to test the effectiveness of a drug that is being considered for possible use in the treatment of people who experience chronic anxiety. Fifty people who are chronically anxious are identified through a local health clinic. Twenty-five people are randomly assigned to the experimental group, and they receive the new drug for six weeks. The other 25 people are randomly assigned to the control group, and they receive the commonly used drug for six weeks. After the treatment period, the participants provide a self-rating on a 20-point scale indicating the level of anxiety they are experiencing (higher scores indicate greater anxiety). The mean self-rated anxiety in the experimental group was 10.2 (SD = 1.5), and the mean rating in the control group was 13.5 (SD = 2.0). The .95 confidence interval for the mean self-rating in the experimental group was 9.6 to 10.8. The .95 confidence interval for the control group was 12.7 to 14.3

Question 1

What is the independent variable in this experiment?

Question 2

What are the levels of the independent variable?

Question 3

What is the dependent variable in the experiment?

Question 4

How would you describe the effect of the drug variable on anxiety ratings using the means for each condition?

Question 5

What claim would you make based on the estimates of the population means for the two groups in this experiment based on a comparison of the confidence intervals?

Question 6

The probability associated with the null hypothesis test for the difference between the two groups was p = .01. What claim would you make about the effect of the treatment based on this probability?

Question 7

The effect size for this experiment is d = .37. What information does this effect size tell you about the effectiveness of the drug?

Answer 1

• ANSWER 1 and 3-The independent variable is the drug being tested to study its effect on chronic anxiety of participants which is the dependent variable.(effect)
• Since,the drug is being controlled and given by the experimenter it is an independent variable.
• ANSWER 2 -There are two levels of the independent variable since,the  experiment is comparing an experimental treatment with a control treatment, then the independent variable (type of treatment) has two levels: experimental and control.
• Due to time limit,remaining questions can be asked as another question,they will be answered,thankyou for your cooperation