A local college requires an English composition course for all freshman. This year they are evaluating a new online version of the course. A random sample of n=16 freshman is selected and the students are placed in the online course. At the end of the semester, all freshman take the same English composition exam. The average score for the same is M=76. For the general population of freshman who took the traditional lecture class, the exam scores form a normal distribution with a mean of µ=80.
a-if the final exam scores for the population have a standard deviation of 12, does the sample provide enough evidence to conclude that the new online course is significantly different from the traditional class? Assume a two-tailed test with and alpha =.05.
b-if the population standard deviation is 6, is the sample sufficient to demonstrate a significant difference? Again, assume a two-tailed test with and alpha =.05.
c-comparing your answers for parts a and b, explain how the magnitude of the standard deviation influences the outcome of a hypothesis test.