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Topic:
Acorn FreeResponse #3
Replies:
2
Last Post:
May 4, 1997 1:52 AM




Acorn FreeResponse #3
Posted:
May 2, 1997 7:34 PM


Yesterday I gave a full 3hour practice AP to my 21 students taking the exam and used the Acorn FreeResponse #3 on it. It asks for a 99% confidence interval for the difference of two means (small sample) to check whether there is a significant difference. Most of my students had forgotten that CI and instead used a hypothesis test of two means, correctly leading them to the same conclusion they would have gotten from the confidence interval. Most then gave an eloquent conclusion that adequately answered the problem. From this list I realize that the problems will be graded between 1 and 4 with half for work and half for explanation. My question is this, if they have adequately answered the question how much will they be penalized for using a hypothesis test instead of the asked for confidence interval? In practice there is no difference in the two methods, so I am not sure how to grade it. It seems awfully harsh to give an excellent response to the question a 3 because they didn't follow the directions and used a hypothesis test, but I feel something must be taken off for it. What do you all think? Kevin Rees The Hill School Pottstown, PA



