Go up to the CS 2150 page (md)
There were 11 full-length labs, and lab 12 which had two parts. Thus, there were 35 lab parts (11 labs of 3 parts each, plus one lab of 2 parts). Lab 5 had the AVL tree worksheet, which counted as 4 more points. So the total number of points for the labs was 35*10+4 = 354. Labs counted for 45% of the final course grade.
Each midterm counted for 15% of the final course grade, even though the total number of points on each midterm was different. The final counted for 25% of the final course grade.
The grade breakdown (how much each part counts for the final grade) is as listed on the course syllabus (md).
For both of hte midterms, we gave a 10 percentage point curve; each midterm was worth 15% of the course grade. Thus, 10% of 15% is 1.5%. For two midterms, that means 3.0 points added to everybody's score.
For the final, we gave a 5 percentage point curve; the final was worth 25% of the course grade. Thus, 5% of 25% is 1.25%.
From the exams, we have 3.0+1.25 = 4.25 added to everybody's course grade.
Yes, we round grades. Note that round(x) == floor(x+0.5). So we added 0.5 points to everybody's curve to take into account rounding. Note that this means rounding is already taken care of, so if you get an 89.9999999999999999999, it's still a B+, no matter how many times you ask - you don't get to round a second time (in reality, it was an 89.49).
The curve so far is 4.25 (from the exams) plus 0.5 (from rouding), for a total of 4.75. We raised that up to 5.0 for the final course curve. Thus, everybody got 5 points added to their average (your average being what the gradebook reports). Note that this already includes rounding, so you don't get to round a second time!
As stated at the beginning of the semester, each 10-point "decade" is a separate letter grade range (60-70 is a D, 70-80 is a C, etc.). The exact ranges, taking into account the course curve mentioned above, are below. Note: the following table ALREADY includes the course curve! So you take your exact average from the gradebook and see where it lies on this table. And rounding has already been taken into account (see above), so you don't get to round a second time.
| Minimum course average | Letter grade |
|---|---|
| 50.0 | D- |
| 58.0 | D |
| 62.0 | D+ |
| 65.0 | C- |
| 68.0 | C |
| 72.0 | C+ |
| 75.0 | B- |
| 78.0 | B |
| 82.0 | B+ |
| 85.0 | A- |
| 88.0 | A |
| 93.9 | A+ |
Note that the A+ range and the D- range follow a slightly different pattern. The A+ range is a percentage of the class (in this case, the top 7 course averages), and thus ended up being 93.9 (no rounding, since it's a fixed number of students). Also, the D- range extends down a bit more.
We've enabled the (terrible) Collab gradebook tool, and imported all the grades into there where they will live for all eternity. Or at least until UVa doesn't feel like keeping them around any more...
For the fall 2016 semester, there were 9,800 lab grades assigned throughout the semester: 275 students times 35 lab parts is 9,625; the difference was from students who dropped or withdrew from the course. There were 284 regrades that were submitted (2.9% of the graded assignments). Of those, 20 were due to extensions, and 87 more did not have any grade change. Thus, there were only 275-20-87 = 168 regrades where a grade was changed. That is only a 1.71% error rate.