Well, if there were one thing to be agreed over by all COEPians,
it will be : The GPA system is both interesting and intriguing, leaving everyone sans any clues even after they finish off the 8 sems.
To understand the system and strategise in accordance with the GPA system is something everyone wants to do but miserably fails at.
This is an account from a US insti educationist, analysing how effective the GPA system is?
Distorting the Record
Consider students X, Y, and Z. Suppose X gets an “A-” in
course #1 with 91.0% and 3 x 4 = 12 grade points. Student Y, taking
the same course, scores 89.0% for a B+, with grade points 3 x 3 = 9,
and Z scores 81.0% for a B, also 9 grade points. Comparing X and Y, a
2% difference in original course performance has produced a 25%
difference in grade points! In other words, the difference between
students has been grossly magnified, with a difference magnification
factor greater than 10X! Yet, comparing students Y and Z, an 8%
difference in score has produced absolutely no difference in grade
points. Is this logical or fair? Absolutely not, because the ability
demonstrated by student Y is much closer to X than to Z.
Given the fact that my college grading system includes one decimal
place in the percentage scores (table, above), how close could
students X and Y be, and still receive different letter grades? My
biology course has 1000 total possible points, 600 from lecture
exams, and 400 from laboratory quizzes and reports. Suppose X gets
900 points out of 1000, and Y gets 899. According to my current
college grading system, student X receives A-, and student Y a B+.
The difference in their performances, 1 point out of 1000 or 0.1%, is
utterly trivial, the equivalent of one incorrect guess on a single
true-or-false question. Yet, a grading system using quality points
records the difference as 25%, with a difference magnification factor
of 250X. How absurd!
What effect does such a system have on people? First, students worry
excessively about every point lost for fear of a borderline near-miss
at semester end. Second, professors are disturbed by excessive
student worry, challenged by complaints about points lost, and nagged
by conscience when assigning borderline final letter grades. The
syndrome can affect final letter grade distribution in a very
negative way, because many professors plot final numerical
percentages of all students graphically, then look for natural
“breaks” in the curve so that borderline grades are minimized. Since
a natural break might occur at 86% rather than 90%, the result is
grade inflation. Third, recognizing that the system leaves something
to be desired, institutions periodically spend inordinate amounts of
time attempting to modify the system to make it more fair. Hence, the
most recent vote at my college is to count the + and – in the GPA
numerical calculation in the future. What is the significance of
adding + and – to letter grades and counting them numerically? This
is akin to improving N, S, E, and W compass points: NE is more
accurate than just E, and NNE more accurate than NE. So B+ is more
accurate than B, and, presumably, B++ even more accurate. By doing
this, what we really hope to achieve is letter grades that reflect
the original numerical percentage evaluations more accurately.
Likewise, NNE really represents only a 1/16th wedge in a 360 degree
directional circle, whereas N represents a far less precise 1/4 wedge.
Is There a Better Way?
Given students X, Y, and Z with 91%, 89%, and 81% respectively, in
the same course, what letter grades are really appropriate? None. No
letter grade will be as fair and accurate as the original percentage
grade. By definition, the percentage grade has at least 100 units of
assessment, and it typically has 1000 units by including one decimal
place, as in my current system. Thus, the ultimate absurdity: the
deserved performance assessments are, of course, simply the original
91%, 89%, and 81% scores.
What happens, then, if the professor never uses numerical
percentages, but rather uses letter grades directly on exams and
papers? These letter grades should be converted into percentages,
using current percentage-letter grade conversions (table, above) in
reverse. Should students receive QPs for these percentages, and
would a GPA be calculated? Absolutely not! Fairness demands that
there be no QPs and no GPA to magnify student differences. Since we
must still take into account the number of credits per course and all
courses taken, performance overview should be determined as
percentage per credit, or PPC. For example, suppose students X and Y
take the same five courses: three 3 credits, one 2 credits, and one 4
credits. Suppose also that student X gets 91% in every course for a
91 PPC, and Y gets 91% in the three 3 credit courses and 89% in the
other two for a 90.2 PPC ((9 x 91%) + (6 x 89%)) ÷ 15 = 90.2%. Both
students would thus be in the “A” category using a 90 PPC standard,
whereas the traditional GPAs of 4.0 for X and 3.6 for Y are
misleading. The situation can be even more ridiculous: if Y received
98% in each 3 credit course, and 89% in the other two, Y’s PPC would
be 94.4, clearly showing superiority to X. Yet the GPAs remain as
before: 4.0 for X and 3.6 for Y.
Now, let’s reconsider the F grade, with zero QPs for anything below
60%. Suppose student X takes five 3 credit courses, and gets 79%,
79%, 69%, 69%, and 59%. The PPC will be 71 (classical C category),
but the GPA is 1.2 (much closer to D). If Y gets the same grades in
the first four, but 30% in the last, the GPA remains 1.2 but the PPC
is 65.2, correctly reflecting the difference in level of F
performance. One more extreme example to make the point: suppose
student Z takes five 3 credit courses, receives 99% in four, but has
one very bad day and gets 59% in the fifth. Clearly, this is a
superior student (PPC = 91), but the GPA is a so-so 3.2.
Some may argue that the GPA is nevertheless acceptable because
borderline grades may not make much difference in the long run. But
why not just get it right? Why begin the grading process with an
accurate numerical evaluation, convert it to a less accurate letter
grade, and back again to a still less accurate number? With its
potential for producing distortion and unnecessary agonizing, the GPA
should be discarded and the PPC, or something better, should take its
Professor William D. Cohen
Department of Biological Sciences