Feedback rules are used **to interpret the answer** and **give appropriate feedback**.

To understand the difference between positive and negative feedback, it's important to understand **SOWISO's evaluation flow**, displayed in the figure below.

### 1: Checking the syntax of the user input (general)

When the student’s answer contains a syntax error, this is immediately shown on the screen. Example:

**2a: Checking the syntax of the user input (for solution evaluation type)**

For some solution evaluation types, it is necessary to get the student's answer in a specific form. For example, the ‘eval equation exact’ evaluation type requires an equation from the student. If, for instance, the equality sign is missing, then an error will be shown to the student:

**2b: Evaluating the student’s answer against the solution definition**

The student’s answer is checked against the solution that is defined in the Solutions tab. If the student’s answer is evaluated as ‘true’, then we proceed to step 3. If the student’s answer is evaluated as ‘false’, then we proceed to step 4.

**3: Checking for positive feedback rules**

If a student’s answer is evaluated as ‘true’ against the solution definition, then the system will look for positive feedback rules that are applicable to the student’s answer. These rules check for instance if the student has simplified their answer enough.

The student will see an orange checkmark and the feedback text of the applicable feedback rule. If multiple positive feedback rules are applicable, the system will show the one with the highest priority. If no positive feedback rules are applicable to the student’s answer, the student will see a green checkmark and have successfully completed the exercise.

Note that not all exercise types allow for positive feedback. If an exercise does not allow for positive feedback, the student will always see a green checkmark and have successfully completed the exercise if their answer was evaluated as ‘true’ against the solution definition.

Example: say we have an exercise where the student has to add two numbers together. The solution definition is shown on the right.

The ‘eval normal’ evaluation type checks if the student’s answer is mathematically equivalent to the Definition field. This means that, without positive feedback rules, the following student’s answer will be marked as correct:

However, the student was not finished with the exercise, as they have not simplified their answer. We can write the following positive feedback rule to fix this problem:

**4: Checking for negative feedback rules**

If a student’s answer is evaluated as ‘false’ against the solution definition, then the system will look for negative feedback rules that are applicable to the student’s answer.

The student will see a red cross and the feedback text of the applicable feedback rule. If multiple negative feedback rules are applicable, the system will show the one with the highest priority. If no negative feedback rules are applicable to the student’s answer, the student will simply see a red cross with the text “Wrong”.

Note that not all exercise types allow for negative feedback. If an exercise does not allow for negative feedback, the student will see a red cross with the text “Wrong” if their answer was evaluated as ‘false’ against the solution definition.

Example: We define one negative feedback rule, which is shown below.

We look at two possible student answers. Our negative feedback rule is applicable to the first student answer. There are no negative feedback rules applicable to the second student answer

**Related articles**

This article explains more about how to create and edit positive & negative feedback rules. This article gives an overview of all evaluation types that you can use for the solution or the (positive or negative) feedback evaluation.