Moodle contains a number of aggregations that are used to calculate the totals for categories and for the course total in the Gradebook. The three aggregation methods are documented below:
These are the three most common methods. However the other aggregations can be accomplished using these three methods. Each aggregation method is very different from the others, and can result in different grade totals.
This aggregation method will sum up all of the points the student could receive. This is the total number of points for the category.
The Gradebook has 4 grade items, a 20 point quiz, a 10 point assignment, a 100 point mid-term exam, and a 200 point final exam. The total possible points would be 330 points.
If the student receives 15 points on the quiz, 10 points on the assignment, 100 points on the mid-term, and 100 points on the final. Their total points would be 225 points.
This aggregation method weights the grades based on the possible points for each grade item. These grades are based on the value of the category total (default value is 100). It is strongly recommended to leave the category total at 100 for this aggregation. As an example a 20 point quiz would have a weight of 20, while a 200 point final would have a weight of 200.
The Gradebook has 4 items, a 20 point quiz, a 10 point assignment, a 100 point mid-term exam, and a 200 point final exam. The total possible points would be 330 points.
A student scores 15 on the quiz, 10 on the assignment, 100 on the mid-term, and 100 on the final. Their score using Simple Weighted Mean of Grades is 68.18%.
Weighted mean of grades permits the instructor to adjust the relative worth of a grade by applying weight factors. These factors are multiplied with the score to increase or decrease the final total for that grade item. Grades are placed on a 100-point scale (normalized). For example if a student scores 9 out of 10 on a 10-point quiz, the score becomes a 90 after the normalization process. Moodle multiplies the normalized score by the weight factor. The weighted scores are then added together. The weights are also added together. Then Moodle takes the weighted scores and divides by the sum of weights to get the category total.
The Gradebook has 4 items, a 20 point quiz weighed at 20%, a 10 point assignment weighed at 10%, a 100 point mid-term exam weighted at 35%, and a 200 point final exam weighted at 35%. The total possible points would be 330 points.
A student scores 15 on the quiz, 10 on the assignment, 100 on the mid-term, and 100 on the final exam. Their score using Weighted Mean of Grades is 77.50%.
The name for the Moodle Gradebook (e.g. Gradebook Workshop) by default is the main category. Aggregation methods can be used in the Gradebook as a whole or on individual categories. You can apply different aggregations to different categories within the same Gradebook.
Settings for the aggregation methods are controlled in that categories configuration area. These settings effect the calculations of the items in that category. If a category has sub-categories then the aggregation method applies to the sub-categories total. Grade items in a sub-category are calculated based on the aggregation method for that sub-category. The sub-category can use a different aggregation than the parent category.