THE GRADING PROCESS (
Course letter grades will be determined from the top down by the overall Course Score (CS), calculated from the Normalized Test Score (NTS), the Normalized Lab Score (NLS), and the Normalized Homework Score (NHS), as follows:
(CS) = 0.60 (NTS) + 0.30 (NLS) + 0.10 (NHS)
Here the normalized test score, NTS, is the normalized value (See Normalization below) of the adjusted test score, ATS, which in turn is equal to the sum of the following scores for best four of the following five test hours: the (normalized) final exam score, weighted double, and the (normalized) scores of the three hourly tests, as described under EXAM POLICY. In other words, the lowest (normalized) scored test-hour is dropped for every student, and the resulting sum, (labeled here ATS) is renormalized into NTS before being included into the Course Score, CS, with the weight, 0.60, specified above.
The Laboratory Score, NLS, is computed from the adjusted raw lab score, ALS, obtained from the raw sum of the semester’s lab report grades, RLS, on the basis of “80% of the Maximum” process described below.
Homework Score, NHS, is similarly obtained from the adjusted HW score,
AHW, obtained from the raw sum, RHS, of the semester’s HW scores by “80%
of the Maximum” process described in below. Occasional in-class quizzes
related to the homework material may also be given from time to time.
Their grades will be added into the raw HW score, RHS, and treated in
the same way as the HW grades.
Students whose Course Scores lie in the top 25% will receive an A. Students whose Course Scores lie in the top 50% will receive at least a B. The A/B break-point will be set where a gap occurs in the course scores which is large enough to distinguish the performance of the lowest-scoring A student from that of the highest-scoring B student. Therefore, in practice, more than 25% of the students will likely get A’s. Likewise the precise B/C break-point will be set by such a gap, so that in practice more than 50% of the students will receive A's and B'
estimate letter grade equivalents from normalized scores, note that
about 50% of the population falls below the average normalized score
of 70. That average is therefore near the B/C letter grade breakpoint.
normalized score equal to 90=(Avg + S.D)=(70 +20) will typically place
a student in the top 1/6= 16.7% of the group, quite comfortably within
the top 25% who are promised A grades. In practise, no letter grades
are computed (apart from the Early Warning
To estimate letter grade equivalents from normalized scores, note that about 50% of the population falls below the average normalized score of 70. That average is therefore near the B/C letter grade breakpoint. Furthermore,
a normalized score equal to 90=(Avg + S.D)=(70 +20) will typically place a student in the top 1/6= 16.7% of the group, quite comfortably within the top 25% who are promised A grades. In practise, no letter grades are computed (apart from the Early Warning
after the first exam) until the end of the course, and then they are
defined by the corse score defined above. (This paragraph was added
Fri 4/8/05 for clarification.)
grades after the first exam) until the end of the course, and then they are defined by the corse score defined above. (This paragraph was added Fri 4/8/05 for clarification.)
who do not complete the course requirements will receive an F. Failure
to complete all of the Labs and submit all the lab reports, missing the
Final Exam, and/or missing two or more hourly exams each constitutes a
failure to complete the course requirements. Generally students who do
complete the course requirements earn a course score sufficient for a
D. Regarding the C-D breakpoint, we shall apply
a prejudice in favor of C by giving D's only to students whose course
scores are separated by a gap from the smooth distribution of the rest
of the class. Thus despite our
prejudice for C over D, a substantial gap between your score and the low
side of the continuous part of the class distribution may be dangerous
to your C.
“80% of the Maximum” is Enough
“80% of the Maximum” process for determining Lab and HW components of
the Total Course Score is based on the proposition that Lab and Homework
are learning experiences, and not exams, and that if they meet a certain
pre-set standard, they should carry no grade penalty. We consider the
achievement of “80% of the Maximum” possible total score to be “good enough”. In addition,
we believe that “80% of the Maximum” is within the reach of every student
who is willing to do the required work.
every student who achieves 80% of the Maximum possible Homework (or Lab)
score will receive the same highest (=100) Adjusted Raw HW, AHW, or Adjusted
Raw Lab,AL, score. Students who achieve
less than “80%of the Maximum” will receive a raw score equal to the percentage
of 80% which they achieve. These raw scores will then be normalized into
NHS and NLS distributions with an Average of 70 and a standard Deviation
of ±20 (just as the adjusted test scores, ATS, are normalized), to yield
the Normalized Lab and Normalized HW scores, NLS and NHS, used to compute
the Course Score, CS, with the above 60-30-10 weighting given in the above
Be Sure to Achieve the “80% of Maximum” Level
We advise everyone to make sure that he/she achieves the highest possible
Adjusted HW and Adjusted Lab score, not just because it guarantees them
the highest normalized HW and Lab scores, but because the failure to do
so may seriously damage their NHS and NLS component scores. The reason
is that the normalization of a distribution in which most of the grades
lie at some maximum value can carry the few lower-than-maximum scores
to quite low values, as discussed further below. The effect is drastic,
but it can be avoided with due care, and it is the flip side of the decision
to treat everyone equally who meets a certain specified threshold.
any two grade components are added, they shall always be Normalized
so that their distribution has an average of 70 and a standard deviation
of 20. Thus if a certain (e.g. your own Exam I, or your adjusted lab
score, ALS, in the formula above) grade has a raw
(i.e., unnormalized) value, R, and comes from
a class-wide distribution which has an average, A, and a Standard Deviation,
D, the corresponding normalized grade is:
This normalization process provides a fair mechanism for dropping the "lowest" of several exam scores, even when one exam may have been much more difficult (i.e., had a lower class average) than the other exams: the normalized scores' distributions for all tests have, by construction, the same average (70) and the same standard deviation (20). Note that the normalization formula can never alter the relative ranking of any student with respect the others in the class: a higher value of R always yields a higher value of N.
|We repeat the warning issued already above: if in the original distribution, nearly everyone has the highest possible score, as we expect to be the case for the raw HW and raw Lab scores because of the "80% is good enough" rule, then the few people who fail to meet that threshold my see their normalized score diminished significantly by the normalization calculation. Indeed, the normalized score can even become negative, although when it does so, we shall intervene and replace the negative score by a zero. This is the flip side of the promise that if you meet the minimal 80% standard, you will earn the maximum credit for HW and Lab: if you do not satisfy this easily achievable threshold, you may wipe out much or all of your credit for the HW and/or Lab segments of the course.|