Aggregation: Natural weighting of Grades

Natural aggregation replaces the Sum of Grades aggregation method. By default, Natural uses the Max Grade value for each activity to determine its weight in a grading category. For example, consider the following syllabus:

Activity	Max Grade	Weight
Forum 1	25 points	12.5%
Forum 2	25 points	12.5%
Quiz	50 points	25%
Assignment	100 points	50%
Course Total	200 points	100%

The above syllabus would appear like this in the Gradebook Setup page of the gradebook:

To determine weight percentages, Natural aggregation divides each activity’s Max Grade by the total available points in the grading category. Forum 1 and Forum 2 are each worth 12.5% of a student’s course grade because 25 / 200 = 0.125. The quiz is worth 25% because 50 / 200 = 0.25. The assignment is worth 50% because 100 / 200 = 0.50.

However, consider an instructor who wants the quiz to have a Max Grade of 50 points, but also wants the quiz weight percentage to be 30%, which is greater than the automatically calculated 25%. Natural aggregation makes it possible to directly input a weight percentage. This override is established by clicking the Weights checkbox, defining the value of 30%, and clicking the Save Changes button as shown below.

Note how the weight override for the quiz forced the system to automatically recalculate the weights of the other activities. When using weight overrides, it is important to verify that all weights reflect the intended percentages. Additional weight overrides for the other activities can be established if necessary. In fact, this optional weight override feature makes it possible to create a gradebook in which the Max Grade values of activities are completely disconnected from their weight percentages if desired.

Furthermore, Natural aggregation supports gradebook features that were previously specific to other aggregation methods:

• Exclude Empty Grades: This feature allows empty grades for activities in a grading category to be excluded from the calculation of a student’s course grade.
• Extra Credit: This feature allows activities to be designated as extra credit. An extra credit activity does not negatively impact the course grades of students who do not attempt it.

In short, Natural aggregation integrates all of the features of Sum of Grades, Weighted Mean of Grades, and Simple Weighted Mean of Grades into a single aggregation method.

Selecting Natural Aggregation

This section outlines how to configure a gradebook to use Natural aggregation.

1. From the course page, click the Gradebook setup link found in the Course Administration block.
   
2. Aggregation is a setting that applies to grading categories, which are indicated by folder icons in the Gradebook Setup page. Click the Edit link for one of the grading categories.
   
3. A small popup menu appears. Click Edit Settings.
   
4. In the Grade Category section, click the Aggregation drop down and select Natural.
   
5. When all desired changes have been made to the Edit Category page, click the Save Changes button. If no changes have been made, click the Cancel button.
   
6. Return to the Gradebook Setup page. For each grading category, repeat the steps of this procedure. Ensure that the Aggregation drop down in all grading categories is set to Natural.
   

Setting a Weight Override for an Activity

This section outlines how to use the optional Weight Override feature, which allows Max Grade point values to be disconnected from weight percentages. More specifically, the following steps show how to enable a weight override for an activity in a grading category.

1. Navigate to the Gradebook Setup page. Note how activities are organized into grading categories, which are indicated by folder icons. In this example, weight percentages have been automatically calculated based on Max Grade point values. Because Assignment 3 is worth 150 out of a possible 250 points in the Assignments grading category, it is worth 60.0% of the student’s Assignments Total.
   
2. Assume that an instructor wants Assignment 3 to be worth 80% of Assignments Total rather than 60%. However, the instructor does not wish to change the Max Grade value of Assignment 3. To accomplish this, a weight override must be used. Click the checkbox next to the Weight field for Assignment 3. This turns the Weight box into a white text entry field that can be modified.
   
3. Change the weight value to the desired percentage.
   
4. Click the Save Changes button located near the bottom of the Gradebook Setup page.
   
5. The Gradebook Setup page reloads. The 80% weight override for Assignment 3 is now saved. Additionally, the system automatically adjusts the weights of Assignment 1 and Assignment 2 from 20% to 10% because no grading category can have a total weight exceeding 100%. Note that the Assignments grading category is still worth 50% of the course grade. Only the weighting of the activities in the Assignments category has changed.
   
6. If additional weight overrides need to be set, repeat the steps of this procedure for the desired activities.

Setting a Weight Override for a Grading Category

This section outlines how to use the optional Weight Override feature, which allows Max Grade point values to be disconnected from the determination of weight percentages. More specifically, the following steps show how to enable a weight override for a grading category in the course.

1. Navigate to the Gradebook Setup page. Note how activities are organized into grading categories, which are indicated by folder icons. In this example, weight percentages have been automatically calculated based on Max Grade point values. Because the Assignments grading category is worth 250 points out of the 500 possible points in the course, it is worth 50.0% of the student’s Course Total.
   
2. Assume that an instructor wants the Assignments grading category to be worth 60% of the course grade rather than 50%. However, the instructor does not want the Assignments Total value of 250 points to change. To accomplish this, a weight override must be used. Click the checkbox next to the Weight field for the Assignments grading category. This turns the Weight box into a white text entry field that can be modified.
   
3. Change the weight value to the desired percentage.
   
4. Click the Save Changes button located near the bottom of the Gradebook Setup page.
   
5. The Gradebook Setup page reloads. The 60% weight override for the Assignments grading category is now saved. Additionally, the system automatically adjusts the weights of the other grading categories because the course cannot have a total weight exceeding 100%.
   
6. If additional weight overrides need to be set, repeat the steps of this procedure for the desired grading categories.

Clearing a Weight Override

Clearing a weight override restores the system to the default behavior of using Max Grade point values to determine weight percentages. The steps involved in clearing a weight override are identical for activities and grading categories.

1. Navigate to the Gradebook Setup page. Identify the desired weight override to clear. Weight overrides are designated by checkboxes in the Weights column. Note: if only one activity exists in a grading category, then that activity will automatically have the weight override checkbox enabled. This is normal system behavior.In this example, assume the instructor wants to clear the weight override defined for the Assignments grading category.
   
2. Click the weight override checkbox to disable it.
   
3. Click the Save Changes button located near the bottom of the Gradebook Setup page.
   
4. The Gradebook Setup page reloads. The weight override is disabled, and the weight percentage is recalculated according to the point value. In this example, because the Assignments Total is 250 points out of a possible 500 points, the weight of the Assignments grading category is 50%.