what happens when a test company gets it wrong

[Don Shepherd]

(10-16-2014 05:11 PM)Han Wrote:  If your domain is the set of integers, then a rational median may seem misplaced.

If your domain is the set of integers, then a rational mean may also seem misplaced, but I don't see anyone arguing for an alternate definition of mean, and I think everyone knows that the mean, or average, is a much more common measure of central tendency than median.

Look, I'm not saying that any other definition of the term median is absolutely and positively wrong, but I would argue that if you are going to use any definition other than the standard one that we teach to the kids, you better have a very large footnote explaining that, because it is not what people would expect.

When we teach median to students, we don't say "this is the standard definition, but you should be aware that there may be other possible definitions ...". That would surely open the door for a student to argue a test question marked incorrect because the student has his own definition!

I think HP is aware that this is a goof and they should have caught it during beta testing before it got out into the real world. If one of my students came to me with a Prime calculator that said the median of {2,5,7,9} was 5 instead of 6, I would immediately ban that calculator from being used by my students. I would deem it mathematically untrustworthy.