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Comai BIS2A. Spring Quarter 2013

Class grade

The class grade is assigned based on your total score out of 500. Table 1 illustrates the score components.

Table 1. Score breakdown

Item Points Percent
Midterm 1 75 15
Midterm 2 75 15
Midterm 3 75 15
Final 125 25
Clicker participation and answers 50 10
Discussion 100 20
Total 500 100


There will be about 4 graded clicker questions per lecture. In general, these will be quite easy. You get 2 pt if you answer right, 0.5 pt if you answer wrong. You can get a maximum of 8pts per lecture and 50pts over the whole course. If you do the math, you will see that you can you miss several lectures and still make 50 pts. Resist the temptation of having somebody else click for you. Cheating will be dealt with severely BIS2A_General_Info.

Final grade

What grade will each score get? The maximum grade cut-off points are shown in table 2.

Table 2. Guaranteed maximum cut-off points

Points Percent Grade guaranteed if you are above cutoff point
450 90 A
400 80 B
350 70 C
300 60 D

For example, if you score higher than 450 you are guaranteed an A. These are maximum cutoffs and the final cutoffs may be lower depending on the class distribution. For an example, see the 2009 Spring Quarter Comai-BIS2A distribution and grade cutoffs below. You will notice that in 2009 ~26% of the class got A- or higher, and ~15% got D+ or less.

Grade and attendance policy


Your presence at lecture is rewarded through "clicker points", 2 for each right answer, 0.5 for each wrong answer. Once you have reached 50 points, you cannot get any additional points.


There is no waiting list to get into this course. You must attend the first discussion session. Grading criteria for the discussion will be explained by your TA.

Missed Exams

If you miss a midterm exam without a proper excuse you will get a score for that exam equal to 60% the average of the two remaining exams. For example, if you miss midterm 2 and your scores for midterm 1 and 3 are 50 and 70 points, you will be given 36 points for midterm 2. If you miss two midterm exams, you will get 60% the score of the graded midterm exam for one midterm and 0 for the other.

Valid excuses

You have the right to a make-up oral exam for any exam you will miss because of severe illness, death or life-threatening illness in the immediate family, and university-sanctioned activity. All these instances will have to be documented.

Frequently Asked Questions

  • 1. Is the class graded on a curve?

Yes, but keep in mind the cut off points. If all students in this BIS2A class get above 476 points and are distributed in a curve between 476 and 500, they will all get A. In practice, the scores of any set students (>100) are typically found distributed in a near-normal fashion between 40 and 95%. I apply curving in adjusting the exact cutoffs by taking into account the average performance of the class. For example, I will decrease the cutoffs to ensure that a sufficient number of students score A, etc. See the meaning of "curve grading" in this web definition. Also, please realize that there are many ways of calculating a curve.

  • 2. According to your table, do I get B if I score 440/500?

Not necessarily, the A cut off may be lower than the one shown (and the other cut offs as well) and will depend on the distribution of the scores. The table only gives the "guaranteed" maximum cut offs.

  • 3. My grade is lower than I want, is there anything I can do to raise it? Such as special assignments, research papers, tune your bicycle, mop the floors in your department, reroof your house, dispatch your enemies...


  • 4. I have been studying your class grade distribution. I believe that you calculated the curve in the wrong way. The formula "curved score = 100*score*RTexp-2/se+Pi" should instead be used. Beside being a better and more elegant equation this would push my grade from C+ to B- which would allow me to fulfill my family's mandate to become an orthopedic surgeon and build myself an eight story mansion before age 40. I intend to argue this with you until you cry "Uncle" and give me what is mine!

I am sorry. I do not engage in discussion over the boundaries or curving the grade. I will not answer any further email on this topic. Feel free however to ask me any scientific question that may be important to your learning.

  • 5. As the scores in the different items (midterm exams, etc) accumulate, can I get a better idea of what my final grade might be?

The best that you can do is to work out your final percent score and match it to the above table or to the 2009 distribution. We do not know the exact score ranges until the very end, when all points have been collected and the score distribution can be computed. By BIS program mandate, the C/B divide is mean-centered on the distribution.

  • 6. My family is engaged in a very special celebration this Spring that happens to take place during Midterm 2. This is in the occasion of my great granpa's 120th birthday. Since he is the oldest man on Earth, a war hero, and my best role model I need to travel to Kathmandu for the festivity. Is this a valid excuse?


  • 7. I have memorized every single word you said during lectures, and each line in the assigned text book pages. So, I know ALL class material and expect to get A. Yet, many of your midterm questions concern matter that was not covered and I could not answer them. This is very unfair!

I understand the problem. See "Preparation for Exams" in the General info page (side bar) of the smartsite. In a kernel, this course requires that you use your acquired knowledge to elaborate answers. Some questions test your ability to "think" rather then merely "remember".

A real grading example: Spring 2009, 2012, 2013-Comai

Table of cutoffs for three years of Comai BIS2A

Grade 2009 2012 2013
A+ 95 94 94
A 87.2 89.8 89
A- 82.3 86.5 83
B+ 78.8 82.5 83
B 75.9 78.5 79
B- 72.4 75 75
C+ 68.9 72.4 70
C 63.6 67 65
C- 59.5 65 60
D+ 56 63 57
D 52.8 55 53
D- 50.2 50 50
F 0 0 0

Figure 1. Distribution of % score and grade cutoffs for Spring 2009 BIS2A

2009 grade.png


Back to BIS2A pages: BIS2A_General_Info - BIS2A_Staff

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