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Re: [Phys-L] rounding

Several people have commented on whether a 3.0 GPA cutoff is reasonable
for teachers. It was not my intention to raise that issue. Yes, it may
be misguided. I think we all recognize that politicians are under
pressure to improve schools and teacher preparation is the easiest thing
to blame. To "fix" it, they feel they need to "increase standards" and
the simplest way to do that is to institute a GPA cutoff. [Pennsylvania
does allow a lower GPA if test scores are higher; and, visa versa,
allows a lower test score if GPA is higher]

My purpose was not to question the choice of a 3.0 cutoff or a cutoff at
all, but rather to ask whether they understand rounding or not.

Christopher M. Gould wrote:
You're confusing the exact value of a number with its representation,
and confusing a physics issue (an experimental value) with a policy
issue (setting a threshold).

When the Pennsylvania Department of Education says "3.0" it does not
mean "something within experimental error of 3.0." They mean the exact
number 3. They themselves recognize that setting their threshold is
arbitrary, but not to set a threshold is a prescription for inaction.

I recognize that an exact 3 cutoff is just as arbitrary as an exact 2.95
cutoff. My point is that stating 3.0, with the GPA rounded to tenth
place is the same as setting the cutoff at exactly 2.95.

Recall that the department of education stated the following:
> The cutoff has to be applied at some point. If the cutoff is
> not 3.0 then it becomes impossible to draw the rounding up
> line.
Seems to me that it is NOT impossible to draw the "rounding up line"...
unless one doesn't understand rounding.

It is also interesting that they say:
> Program providers may not round up the final GPA to a 3.0 for
> the purpose of recommending a candidate for certification.
When, in practice, all institutions round, depending on the software
used to display the GPA. And, institutions do not round the same

For example, let's say a student has a GPA of 2.9971 (possible with plus
and minus grading). The department of education can "say" this is not
sufficient (because it is less than an "exact" 3) but, in practice, it
depends on what institution the student is at (or what registration
system the institution is using). Last year, our registration system
would have reported this as a 3.00 and this student would have been
approved, despite what the department of education says. This year, our
registration system reports it as a 2.997 and the student is not
approved. Same university. Same courses. Different result.

Yes, yes...I know -- what's the big deal? It just seems to me that they
don't really understand rounding (or they don't think institutions
understand rounding). No biggie.

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