Suppose an SAT tutoring company really can improve SAT scores by 10 points, on average. A competing company, however, uses a more intense tutoring approach and really can improve SAT scores by 15 points, on average. Suppose you've been hired by both companies to test their claims that their tutoring improves SAT scores. For both companies, you will collect a random sample of high school students to undergo tutoring. With both resulting samples, you will test the hypothesis that the mean improvement is more than 0. Suppose it is important to keep the power of both studies at 80%. Will you use the same sample size for both studies? If so, explain why you can. If not, which study would require the larger sample size, and why? Assume that both samples of students will be drawn from the same population.
Answer to relevant QuestionsResearchers are interested in testing whether a video game that is designed to increase brain activity actually works. To test this, they plan to randomly assign subjects to either the treatment group (spend 15 minutes per ...A lacunar stroke is a stroke in which one of the arteries supplying blood to the brain is blocked. A randomized, double-blind study was done to see whether recurrence of stroke could be prevented by adding a drug ...Platelets are an important part of the blood because they cause the blood to clot when that is needed to stop bleeding. The drug eltrombopag (which we shall henceforth refer to as EL), was tried on patients with chronic ...The alumni office wishes to determine whether students who attend a reception with alumni just before graduation are more likely to donate money within the next two years. a. Describe a study based on a sample of students ...One treatment for multiple myeloma (cancer of the blood and bones) is a stem cell transplant. However, in some cases the cancer returns. McCarthy and colleagues reported on a study that randomly assigned 460 patients (100 ...
Post your question