Hello,
Is it possible to use the Moodle Gradebook formulas to calculate the average of the highest 13 units of a 15 unit course?
I am running a course in which students are required to do 13 of 15 units. Each unit consists of about 10 graded activities. They may do any 13 of the 15 units (i.e. they do not need to do 2 of the 15 units). If they do less than 13 units, their final score will still be the average of 13 units. If they do 14 units their lowest unit will be dropped from the calculation. If they do all 15 units their two lowest units will be dropped from the calculation.
Put simply, the Final TOTAL = Highest 13 units ÷ 13
I have attached an Excel file to illustrate how this calculation is done with Excel.
Can this calculation be done within the Moodle Gradebook (we are using Moodle 1.9.3+)?
Note, it is possible to drop the lowest X number of grades (see Drop the lowest help), but this function is carried out regardless of the number of units completed. For example, even if a student only does 5 units, his lowest X units will be dropped. We only want unit scores dropped IF students have done more than 13 units.
I suspect this is not possible given that we can't use IF functions in the Moodle Gradebook. Still, suggestions will be most welcome.
How to calculate average of highest 13 units out of possible 15 units? It's not that simple, or is it?
Peter Ruthven-Stuart གིས-
Number of replies: 5
In reply to Peter Ruthven-Stuart
Re: How to calculate average of highest 13 units out of possible 15 units? It's not that simple, or is it?
Bob Puffer གིས-
Sorry, 1.95 and beyond is so much more functional I can't recommend other than to upgrade and set the overall course category to "keep highest" 13 grades, which would be among the fifteen categories of graded items.
In reply to Bob Puffer
Re: How to calculate average of highest 13 units out of possible 15 units? It's not that simple, or is it?
Peter Ruthven-Stuart གིས-
Hello Bob,
Thank you very much for your reply. Yes, you're right, there have been some significant improvements in and additions to the Gradebook. I'll have to wait for our system to be upgraded in order to keep the highest 13 grades.
Thank you very much for your reply. Yes, you're right, there have been some significant improvements in and additions to the Gradebook. I'll have to wait for our system to be upgraded in order to keep the highest 13 grades.
In reply to Peter Ruthven-Stuart
Re: How to calculate average of highest 13 units out of possible 15 units? It's not that simple, or is it?
Itamar Tzadok གིས-
Not sure I follow the problem. If a student completes only 5 units, the student has 5 non-zero grades and 10 zero grades, and if the two lowest are dropped then the student remains with 5 non-zero grades and 8 zero grades, which is exactly what you want. 
In reply to Itamar Tzadok
Re: How to calculate average of highest 13 units out of possible 15 units? It's not that simple, or is it?
Peter Ruthven-Stuart གིས-
Hello Itamar,
Thank you for your reply.
What I am after is a formula that will drop the lowest two grades ONLY IF a student has done more than 13 units, and then divide the total by 13 regardless of how many units a student has actually done. So the problem with dropping the lowest two grades regardless of how many units a student has completed is that even if a student does the required 13 units, two of these grades will be dropped thus penalizing them because their total will still be divided by 13.
Thank you for your reply.
What I am after is a formula that will drop the lowest two grades ONLY IF a student has done more than 13 units, and then divide the total by 13 regardless of how many units a student has actually done. So the problem with dropping the lowest two grades regardless of how many units a student has completed is that even if a student does the required 13 units, two of these grades will be dropped thus penalizing them because their total will still be divided by 13.
In reply to Peter Ruthven-Stuart
Re: How to calculate average of highest 13 units out of possible 15 units? It's not that simple, or is it?
Itamar Tzadok གིས-
If I'm not missing anything here I don't think you need any special formula. Let's say each unit is a grade. So you have 15 units and 15 grades. You set the course total to drop the lowest 2. So you remain with the highest 13 and the course total will be divided by 13. That's it. If the student has completed less than 13, the highest 13 will include some 0 and the course total will still be divided by 13. The drop the lowest two grades ONLY IF a student has done more than 13 units clause is irrelevant.