[LON-CAPA-users] assigned_score and unexpected results

[Raeburn, Stuart]

Doug,

You stated: "... is a one-part problem with 7 customresponses", and "All of the other 6 customresponses are weighted at 0."  Could you clarify how the "weighted at 0" is implemented?

If the award is: "ASSIGNED_SCORE", then during grading LON-CAPA will loop over all the response items in the problem part, accumulate the awarded value for each, and then divide by the number of response items to calculate the value to store for resource.$id.awarded.

The points shown with then be the weight * resource.$id.awarded.  (Weights apply to problem parts).

So, if you have 7 response items, and return (ASSIGNED_SCORE,1) for 6 of those, and return ASSIGNED_SCORE,13/15) for the seventh, then the value of resource.$id.awarded will be:

(13/15 + 1 + 1 + 1 + 1 + 1 + 1 )/7

which evaluates to: 0.9809524

When multiplied by a weight of 5, the result is: 4.904762, which is what you were seeing in course context/

Stuart Raeburn
LON-CAPA Academic Consortium

________________________________________
From: LON-CAPA-users <lon-capa-users-bounces at mail.lon-capa.org> on behalf of Mills, Douglas G <dmills at illinois.edu>
Sent: Wednesday, March 20, 2019 11:22 AM
To: Discussion list for LON-CAPA users
Cc: Mills, Douglas G
Subject: [LON-CAPA-users] assigned_score and unexpected results

Hi All,

I have a word search activity implemented in Lon-Capa worth 5 course points if completed with no hints. There are 12 words to find plus 3 "starter points" that you can spend on 3 different hints for a total of 15 possible points. In the course parameters I've weighted the activity to 5 points. In the activity itself I've used assigned_score as follows:

if($submission eq "12|3"){return (ASSIGNED_SCORE,15/15)}; #12|3 means all words found and no hints used, etc.
if($submission  eq "12|2"){return (ASSIGNED_SCORE,14/15)};
if($submission  eq "12|1"){return (ASSIGNED_SCORE,13/15)};
if($submission  eq "12|0"){return (ASSIGNED_SCORE,12/15)};

My expectation then, for example, is that if I complete the puzzle using two hints, in the course I should see 4.333 points awarded.  However, what I'm seeing in the course for that outcome is a score of 4.90476190476191 out of 5.

The Word Search problem itself is a one-part problem with 7 customresponses; however, the score should be coming from only the customresponse with the assigned_score section shown above. All of the other 6 customresponses are weighted at 0.

So what am I missing?  Thanks!

Doug

Douglas Mills
Director of Instructional Technology
Department of Chemistry
University of Illinois