Dennis Roberts <[EMAIL PROTECTED]> wrote:
> if we take the infamous #39 item ... where the options were (if i recall)...
> A. mean only
> B. median only
> C. range and mean
> D. range and median
> well, even if we accepted this item as "fair" ...
> a student looks at the graph ... sees that there is a bunch of stuff in the
> boxplot ... and then sees A and B ... without too much thought ... they
> could say, it can't be mean or median ONLY ... there must be more you can
> do with that boxplot than that ... so, without knowing anything of
> consequence about boxplots ... you are down to a two choice item
> thus, for even the uninformed ... we have essentially a T and F item
> but, if you did happen to KNOW that the boxplot uses the median ... then
> the fact that the RANGE is part of the C and D options ... means the term
> RANGE is irrelevant to the item ... given that A and B are just too
> restrictive (because of the use of the term ONLY) and C and D have RANGE as
> a common element ... so, if you did pick D ... then it has to be because
> you knew that isolated "fact" ... which certainly is about as low level as
> you can get
And furthermore, not all the wrong answers are equally "bad." Someone who
would answer A or B must know quite a bit less than someone who would
answer C (in fact, it would tend to indicate that they had no concept at
all of what the boxplot represented).
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