An experiment in teaching research methods in psychology was recently conducted at a large university. One section was taught by the traditional lecture-lab method, a second was taught by an all-lab/demonstration approach with no lectures, and a third was taught entirely by a series of videotaped lectures and demonstrations that the students were free to view at any time and as often as they wished. 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. Test whether teaching method affected student performance on the final exam. Use the .05 significance level. What is the null hypothesis

from the question, we were not given the P-value. If the test result were statistically significant, this means that P < 0.05 , thus we will reject the null hypothesis. if P < 0.05, then we are saying that the probability that the teaching method affected the students in their final exams is less that 5%. hence we reject the null hypothesis.

on the other hand if the test result is not statistically significant, this means that the P-value, P > 0.05, thus we will fail to reject the null hypothesis because the probability that the teaching method affected the students performance in their final exam is greater than 5%.