Reference no: EM132286227

1. A medical researcher wants to investigate the effect of different pain medications on people suffering from migraine headaches. Twenty-one people who had recently seen a doctor for migraine headaches were randomly assigned to receive one of three pills: drug A, drug B, or  a placebo (drug C). Each participant recorded their pain level three times a day at regular intervals for one week (pain was recorded on a 1 to 10 scale, with higher scores indicating greater pain). The average pain level over the one-week period was calculated for each participant and is reported below. Use the five-step model to test the hypothesis of no difference in the reported pain levels between the groups. Test at α=.05.

2. An experiment in teaching introductory biology was conducted at a large university. One section was taught by the traditional lecture-lab method, a second was taught by an alllab/demonstration approach with no lectures, a third was taught entirely by a series of videotaped lectures and demonstrations that students were free to view at any time and as often as they wanted. Students were randomly assigned to each of the three sections and, at the end of the semester, random samples of final exam scores were collected from each section. Use the five-step model to determine if there is a significant difference in student performance by teaching method. Test at α=.05. How much of the variation in student performance can be explained by teaching method?