<p>I’m saying that saying 90-100% = A, 80-89% = B, etc (or whatever system you use) IS arbitrary. It does not reflect at all how much you learned. </p>
<p>Since you can’t seem to understand my already extreme analogies, let’s make them even more extreme. Suppose you have a college introductory chemistry class of 200 students. You evenly and randomly divide them into two groups. One group takes a middle school science test, while the other group takes an exam for a graduate level course at MIT. The average for the first group is 97%, while the average for the second group is 3%. Would you say that the second group only understands a small fraction of introductory chemistry compared to the first group? Did the second group “clearly demonstrate that they did not understand the material?”</p>
<p>If you manage to find a way to get a 30% (or higher) success rate in cloning animals, you’ll be lauded as a hero by the scientific community and will probably be given a Nobel prize. However, if you have a 95% success rate in manufacturing screws, you have completely failed.</p>
<p>And FYI, I’m a biology major.</p>