Re: [Phys-l] rich context luncheon meat

[John Denker <jsd@av8n.com>]

Simplicio:  You know, last night my daughter was arrested for 
  robbing the liquor store again.  At least this time she was 
  wearing her fishnet stockings.  You know how I hate it when 
  she leaves the house without any stockings.

Sagredo:  I see you are grading on a curve.

Simplico:  Oh, yes.  Who knows, maybe next time she will wear
  even more, maybe pants or a skirt or something.


On 01/28/2011 05:53 AM, Dr. Richard Tarara wrote:

> ... the Heller problems are, IMO, a clear step up from  back 
> of book problems. 

I see you are grading on a curve.

IMHO you have two problems:
 a) The Heller problems are an embarrassment.
 b) If the textbook is worse, that doesn't solve problem (a).

>  Extraneous information, more complex setups, more info 
> that must be inferred are part of this set. 

In the examples I saw, the "extraneous information" was utterly
superficial and transparent ... as transparent as fishnet.
 -- The problem mentioned a "secret mission" but gave no details.
  Any 3rd-grader would know that the "secrecy" of the mission
  did not have any relevance to the required rate/time/distance 
  calculation.
 -- The problem mentioned submarines but gave no details.  This
  is equally superficial and transparent.
 -- The problem mentioned the ocean but gave no details.  Again,
  utterly superficial and transparent.

In contrast, if the exercise had said that the submarines had a
top speed of 20 knots on the surface and 30 knots submerged, then 
I would count that as nontrivial extraneous information.  I'm not
saying that by itself would transform this example into a good 
example, but at least then we would have a common understanding 
of what "extraneous information" means.

>  True 'real world' problems are the ultimate goal,

Agreed.

Yesterday the Heller problems were called real-world problems. Today 
there is some recognition that they are not "true" real-world problems.  
That's a clear step up in the right direction.