# I don't understand grade curving.

1. Oct 15, 2009

### General_Sax

So far in my university career, I've managed to score near bang on to the class average on every test I've taken.

If I continue preforming at this level, will my GPA be ~ 2.0?

2. Oct 15, 2009

### Staff: Mentor

As for me, if everybody in one of my classes does well, I have no problem with giving them all A's.

3. Oct 15, 2009

### lisab

Staff Emeritus
Most of my physics classes were graded on the curve, and the average was set in the neighborhood of 2.6 to 2.8.

4. Oct 15, 2009

### sportsstar469

that's how it should be in my opinion. set standards that need to be achieved in order to recieve an A, and those who meet those standards recieve A's/ i think its retarded, to curve students grades. Tha's basically saying, that even if a student has shown mastery in a subject, yet did not score as high as some others in class, the requirements were now raised to receive an A, and he gets a b. its bs.

5. Oct 15, 2009

### nicksauce

6. Oct 15, 2009

### Pengwuino

Curves are usually put in place when this is not even close to the case. I've never heard of someone actually getting a B because too many people got A's. Curved classes are usually because most people do poorly in the class and not enough get A's and the instructor deems it necessary that a certain # of people do get those A's.

7. Oct 15, 2009

### symbolipoint

Attempt to explain what Pengwuino is trying to say:

Grading on a curve is a way to assign grades based on central tendency. Too far below central value could be D. Far enough above central value could be A, or B. If a class has an average test score of 50% and some student received score of 75%, he might have A or B, depending on how the data of the class groups are spread. The average class score of 50% would have resulted from the test being hard, or very hard.

8. Oct 15, 2009

### General_Sax

Where my understanding falls apart is here:

The system doesn't seem to be linear, from what I've heard. Some people have told me that if you recieve the exact average grade on every assignment/test/lab/etc, your GPA will be higher than 2.0

In my mind exact average equates to a 2.0, the exact middle of the 4.0 scale.

Am I missing something here? Am I confusing mean with median? I was never very good with statistics.

9. Oct 15, 2009

### nicksauce

That's like saying that if the maximum height of someone is 7 feet, then the average person will be 3 and a half feet tall.

10. Oct 16, 2009

### whs

I'd like to add that going to professor's office hours might help boost grades too, thus further confusing the curve/grading system.

I had a class where I should have made a B (around 82%) after the grade curve, yet I talked to the professor so much that I ended up getting an A. (It was political science - blah)

11. Oct 16, 2009

### Klockan3

Getting 2.0 basically means that you failed, you can't really have that the average person in every class would be failing.

12. Oct 16, 2009

### symbolipoint

General_Sax refers to the grading scale of 4.0=A, 3.0=B, 2.0=C, 1.0=D. According to this scale, a "2.0" would be AVERAGE, a grade of C; certainly NOT failing.

13. Oct 16, 2009

### jambaugh

The grading policy for a class should be outlined on the course syllabus made available the first day of class or before the initial period of dropping and adding classes ends. That way if you don't like the policy you can bail. Now if the instructor or professor deviates from the syllabus to your harm you should be able to appeal. Speak first with the professor, then the chairman of the department, then the dean of the school, then the appropriate vise president and finally president of the university. If you feel you still have grievance you can even go to the state board of regents (assuming it is a state university system institution). If you still feel you have a case you may then hire a lawyer and try the court system.

I outline this as the general course of appeal whether it is over a grade, harassment, or whatever.

With respect to curving grades. I feel that a subject involving mastery such as physics or mathematics should be graded objectively (not on a curve).

If that is the case then cases where all students receive A's or all receive F's should be allowed (but in the latter case they should sue for tuition since their uniform failure indicates the course though possibly evaluating correctly did not provide the instruction and resources to make mastery of the subject possible.)

I (in my mathematics courses) however have used a curve on single exams when due to length vs time available or other reasons that a given test was overly difficult and the percentage correct grade didn't reflect students proper level in the class. However this I explain on my syllabus and assure the students will never be used to lower their grade, only improve it.

As to how I curve it may appear non-linear. A "proper" curve is actually an affine linear transformation. The grades are translated and scaled. When no other criterion need to be met I generally shift the class average to 75 (middle C on a 90,80,70,60 cutoff scheme) and scale so that 90=A/B and 60=D/F cutoffs lie one standard deviation from the mean. That establishes about 15% A's and 15% F's. But that is a rule of thumb. I'll up the average if I feel the class has been above average compared to other classes or as when I usually am curving a single test I will up the average to the class average prior to the test if it was higher than 75%.

I use a curve rather than simply shifting grades because typically an overly difficult test will yield a much higher spread of grades than will an overly easy one. Poorer students though having mastered some of the skills will have a disproportionately harder time getting fully correct answers in a fixed time interval.

Ultimately one must ask in the assessment process what that grade represents. It may be appropriate that students compete for grades and their value represent their relative merit. I don't agree but I allow that I may be mistaken.

I'm of the opinion that the grade assigned needs to be an objective evaluation of the degree of mastery of a subject, especially as that is used to decide on level of preparation for further advanced topics or entry into a program of study.

A student's grade should be independent of how well or how poorly other students in the class have done and only reflect his performance. I use curves as little as possible and were I have goofed in the level of difficulty of a test I will try other means first such as allowing the students a follow-up assignment, before I simply curve a test grade. But sometimes this is not practical as for example on a final exam.

14. Oct 16, 2009

### Klockan3

Ah sorry, I remembered the US grading system wrong. C is the passing grade, but it is also the lowest passing grade possible since you are not allowed to count courses you get D on for your graduation.

So the average student should not have 2.0, the worst student who still graduates shall have that.

15. Oct 17, 2009

### Bourbaki1123

Actually, the worst student could have a GPA below 2.0, because a D is still passing. If you don't get a C in a course that is a prerequisite for another course, you can't take the next course until you retake the other one, but you could conceivably have some F's and D's on your transcript and get a degree. I wouldn't be surprised if there were a few people with a 1.5 average.

16. Oct 17, 2009

### symbolipoint

Whether grade of D is understood as passing or not, it is a grade indicating BELOW AVERAGE, and is obviously not a desired nor useful result. Actually, because of grading by a curve, students can sometimes receive grades which are higher than what they should be, therefore such students can reach the next course and not be able to succeed.

Earning a D (or an F) in a course is something which needs to be repaired or prevented. The course needs to be repeated; some academic counseling, maybe tutoring, and careful self-reflection may be needed.

Which is better? Grading by class curve, or grading by strict scale like 90,80,70,60? Difficult to say. This depends on the teacher, the department. My guess is if the teacher believes the course is difficult, he might choose curve-grading. If he focuses on competence as the result of learning, he might choose a strict pre-determined scale

17. Oct 17, 2009

### lisab

Staff Emeritus
It really depends on the institution. Some schools require a C in the core classes of the major. This is where the old expression comes from, for a grade earned by a student who is passed despite being not quite up to par: the "Gentleman's C".

18. Oct 17, 2009

### Gear300

We don't understand everything. That is why we have a grade curve.

Last edited: Oct 17, 2009
19. Oct 17, 2009

### General_Sax

I actually did some research on prior grades (years) of my course, and found that the average grade was in the range of 2.6-2.8. This allowed for entrance into most second year programs of my interest, barring entry to only the more ... involved courses.

Thanks to everyone who took time out of their days to reply to my post.

20. Oct 18, 2009

### Klockan3

You do not get a degree if you have less than 2.0 at most colleges. You can graduate high school with 1.0, college with 2.0 and grad school with 3.0. Less than that and you wont graduate.