In: Statistics and Probability
An MCAT is an exam that university students take if they are interested in applying to med school. A professor at the University of Guelph quotes the following: "Because only a minority of university students actually take the MCAT, the scores overestimate the ability of a typical university student. The mean MCAT score is about 508, but I think that if all students took the test, the mean score would be no more than 450". This professor gave the test to a random sample of 500 students in Ontario, and found that these students had a mean score of x = 461.
a) Is this good evidence against the claim that the mean for all students is no more than 450? For the purpose of this example, let us assume that the population standard deviation σ of MCAT scores in our Ontario population is 100.
b) would this statistically significant result be practically significant?
b) Would this statistically significant result be significant in a practical sense?