Dennis Roberts wrote: A precursor to this is the basic idea that they have to have OF average ... OF center ... w/o that ... they won't have a clue So, where is it in school ... or home ... that this notion of "average" first (approximately) takes place?
Dennis Roberts I was doing an experiment. I had my method of teaching students the concept of standard deviation, and as a control I taught students the concept of standard deviation by teaching them the formula and letting them use the formula. I think with the formula, students (introductory psychology students) would score about 4 of 12 on my test. With my method, they would score 6 or 7. I was using a one-week delay in testing, and I thought to see what would happen if I tested their understanding quickly. Obviously, it would simplify the experiment. And for whatever reason, I threw in a control group that wasn't taught anything. I called it dispersion instead of standard deviation, and I gave a few examples. They scored about 10 out of 12. So I gave up on my research. What I took from this is that students enter college with a concept of dispersion. If you teach standard deviation, it is important not to disconnect it from their concept. Which is a long way of saying that at the college level, I am pretty sure students enter your class with the concept of average. As I wrote in another post, I suspect average (or center) is more primitive than total. But if I try to test/teach third-graders about average and dispersion this year, I will tell you how they do. Bob . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
