Question

your job is to identify the variables and change the experiment so it does not have any other explanations. audience the target audience is other psychologists. situation the challenge involves dealing with a flawed experimental design. product, performance, and purpose you will create a paper in order to demonstrate your knowledge of experimental design. standards and criteria for success your performance needs to include: identify the independent and dependent variables in this experiment. in a paragraph, describe why the investigators “randomly assigned” the participants to the three conditions. do you agree with the conclusion of the researchers? write a paragraph describing an alternative explanation for the result. also, write a paragraph describing how the experiment might have been designed so as to rule out the alternative explanation that you provided. scenario: researchers posted ads in the newspaper to recruit participants for their study of a new treatment for agoraphobia (the fear of open places). 87 people responded to the ad, but only 60 of those actually reported being agoraphobic. of the sixty, 20 were randomly placed in a condition (new) in which they received the new treatment. it was explained to the new participants that the treatment they would be receiving was promising but new, so they would be monitored carefully to watch for any undesirable side - effects. twenty other participants were assigned to a condition (old) in which they received an older, more traditional form of treatment. these participants were told that they were not receiving the new treatment but an older treatment that had been around for a while, so the chances of side effects were minimal. finally, 20 other participants were randomly assigned to a group (no) that received no therapy. after six months of treatment, researchers found that the participants in the new condition were exhibiting 64% fewer symptoms of agoraphobia than before they started the treatment. participants in the old condition were exhibiting 42% fewer symptoms, and participants who did not receive therapy exhibited 22% fewer symptoms than six months ago. researchers were pleased with the results, concluding in an article they were writing that a new treatment had been found that will be more successful with agoraphobics than previous treatments.

Explanation:

1. Independent and Dependent Variables: The independent variable is the type of treatment (NEW, OLD, NO). The dependent variable is the reduction in symptoms of agoraphobia. This is because the type of treatment is being manipulated by the researchers, and the change in symptoms is what is being measured.
2. Random Assignment: Randomly assigning participants to conditions helps to ensure that any differences between groups at the start of the experiment are due to chance rather than pre - existing differences. This increases the internal validity of the experiment, making it more likely that any differences in outcomes are due to the treatment and not other factors.
3. Agree with Conclusion and Alternative Explanation: It's not certain if the new treatment is truly more effective. An alternative explanation could be the placebo effect. Participants in the NEW group knew they were getting a new, promising treatment, which might have influenced them to report fewer symptoms regardless of the actual treatment's efficacy.
4. Improving the Experiment: To rule out the placebo effect, a double - blind design could be used. Neither the participants nor the researchers interacting with the participants would know which treatment (if any) the participants are receiving. This would reduce the influence of expectations on the results.

Answer:

1. Independent variable: Type of treatment (NEW, OLD, NO). Dependent variable: Reduction in symptoms of agoraphobia.
2. Random assignment helps ensure groups are comparable at the start, increasing internal validity.
3. May not agree due to possible placebo effect. Participants in NEW group's expectations could have influenced results.
4. Use a double - blind design to reduce the impact of expectations on the results.