Hello,
I am using the tracking module markbook grading graph, and I wanted to know how can I assign a grade such as “Not Applicable” to the value of 0. Currently, all the grades in the grade scale are assigned a value greater than 0 and that affects the graph and the mean in the tracking data graph. Is it possible to assign the value of 0 to multiple grades in the grade scale?
Hi vishalr, this is a really interesting question. The issue stems from the fact that the creation of the graph requires data on multiple scales to be compared, meaning that they are all converted to a 0 to 1 scale. This conversion takes the following form:
gradeWeighted = round(gradePosition / totalGrades, 2);
gradePosition is the number of other values below a grade within a scale, plus one, and totalGrades is the total number of entries in the scale.
So, in a scale that runs A, B, C, D, E , a grade B would produce a gradeWeighted or 4/5 or 0.8. An A would produce a 1.0 and an E would produce a 0.2.
As such, you are right that no grade will produce a zero. I guess that when we designed this, we had in mind scales like 7-1 and A-E, where there is no zero value.
Your workaround of having two 0s at the end of a scale is not allowed in Gibbon, as grade scale entries need to be unique.
We could adjust the formula, but this might produce adverse effects for others.
Cheers,
Ross