Hello Dennis and All --
Please pardon the formatting of my response here -- apparently I cannot
choose a different font, so I will bracket my comments by "-->" and "<---."
Dennis writes...
<Snip>
since i was not the person posting the original item on this matter ... i
do know in fact what the real purpose was for this particular item and, i
do not know what the mass. objectives are ... and the material presented in
typical classes ... that then finds its way on to the assessment test
i would say however ... that IF the test included only 6 items related to
statistics ... out of the larger test ... then the issue of whether in a
boxplot ... the vertical bar...
<Snip>
is the mean or median ... is trivial no matter what state the test is for
...
---> I certainly would not argue that the question is anything but
trivial, but that does not necessarily mean it is not legitimate question
for the purposes intended. The "worth" of an individual question should be
judged by its contribution to the overall objectives of the test itself.
One might argue, for instance, that the 6 probability and statistics
questions (if that there be) should span a range of difficulties from
relatively easy to relatively difficult, in order to get a relatively global
picture of what a student knows, in order to inform future instruction.
Suppose (as certainly seems reasonable) that this is a very easy question,
and almost nobody gets it right. One hopes that such a circumstance would
inform future instruction. On the other hand, suppose almost everybody gets
it right. If nothing else, one might redefine the levels of difficulties of
questions for next year's test. Or, one might not, depending on the
politics...
There is another variable in play here, that being the politics involved.
I am not familiar with the MCAS test, nor for that matter, the curriculum in
Massachusetts. However, I can imagine a public uproar if a high stakes test
delivered low percentages of correct scores for a significant part of the
population, unless there was a very low cut score for passing. (I'm
remembering that North Carolina went that route, to the amusement of many.)
The untrained public might be perceived by the testors as having little
truck with an argument that low percentages were OK because the test was
relatively difficult. Thus, it is at least conceivable that trivial
questions would be encouraged in this sort of exam. Do I think this would
be good assessment practice? No. But I don't think good assessment
practice is driving these tests -- politics, in the form of legislatures
are.
<------------
IF indeed there is an item on the test related to a boxplot ... then it
should be about interpreting data using the boxplot ... not about some
ditzy little tidbit that the line in the center part ... or the + sign
above ... is the mean or the median ...
-----> Cannot disagree there, but it would depend on the purpose, use, and
interpretation of the test. If I'm going to deny graduation to some
individual on the basis of this test, I'd sure like a test that clearly
demonstrates the kid is clueless before going into court. A test consisting
of very simple items would accomplish this.
<-------
-- Chris
Chris Olsen
George Washington High School
2205 Forest Drive SE
Cedar Rapids, IA
(319)-398-2161
=================================================================
Instructions for joining and leaving this list and remarks about
the problem of INAPPROPRIATE MESSAGES are available at
http://jse.stat.ncsu.edu/
=================================================================
