Re: [Phys-l] Paul Z's Physics book

["clement" <clement@hal-pc.org>]

One of the problems with reviews of texbooks is that the reviewer usually
understands the material, and also can read the text and understand what it
is saying.  As a result, anything that seems to do a thorough job will pass
muster.  One must have experience and knowledge of the research to begin to
see why specific things are useless, counterproductive, inaccurate ...  But
in addition one should be able to zero in on little things that are
obviously wrong.  A typical professional can not really spot things that
will cause students difficulties.

Most readers would simply not notice things like graphs that are inaccurate
or have defects like lines of best fit that are not.  Students actually do
not notice most of these things either, but they still do randomly pick up
on mistakes and incorporate them into thinking, especially when the mistakes
confirm their misconceptions.  So, one should be very careful when looking
at reviews.  Reviews of novels are much easier because you can sometimes
find a reviewer who can tell you about the things that you would find
enjoyable.  But reviews of texts should be done by professionals who have
been trained to spot the problems.  It is now well known that graduate
students often hold many misconceptions as shown by the FCI, so their
opinions are not necessarily valuable.

An example of how Paul Z's text shows the usual deficiencies is in the
section on significant digits.  Nowhere does he show why the rules he gives
are valid.  Worse yet, he states the addition rule in an abstract way, when
a simple demonstration of addition in columns would illustrate how it works.
He has tried to incorporate research into the book, but only at the edges.
Most chapters need to be rewritten into a learning cycle format if the book
is to be really research based.  This means that first concrete evidence
must be presented, and then a general rule is extracted.  Anton Lawson very
conclusively showed that by simply changing the order of text to conform to
a learning cycle, the comprehension and understanding increased
dramatically.  The example of significant digits is typical that the general
rule is stated with no justification.

PER is not just about making changes in classes that seem to work.  It is
actually about the teachers learning how students are actually thinking, and
what strategies do or do not work well with particular students who have
specific disabilities.  Once one has a new paradigm for learning, the
problems in texts become very obvious.  So what seemed to be student
friendly can be revealed as completely the opposite.

Incidentally my comment about the heating curves being inaccurate seems to
be true in many texts.  It looks suspiciously like the artists have all
copied the same inaccurate drawing, and nobody has looked at the result
critically.  As a matter of fact many texts have the same stock drawings.
One of my favorite goofs in a well known text is where they show a cooler
with drinks, ice, and water.  Then the text proceeds to talk about how the
temperature of the water rises starting at 5 degrees in the "ice water".

Students often suffer from the several cognitive deficits that are
reinforced by the numerous problems with texts.  Most students seem to have
blurred and sweeping perception, episodic perception of reality, excessive
impulsiveness, and a lack of appreciation for the need for precision and
accuracy.  These are not helped by the texts which fire concepts at the
students like buckshot, and that have inaccurate drawings.

John M. Clement
Houston, TX

> It's also possible to check a reviewers other reviews.  The first person's
> review seemed to be reasonably well written.  I check their other reviews.
> They reviewed a variety of statistics books and gave them all relatively
> high marks.  They stated they were a graduate student in something (I don't
> recall the field).  
>
> I didn't check the other reviewers history.