What is Category Impact?
Category Impact tells you how much a specific group of questions influences the overall grade. Categories with more possible points have a greater impact, even if the user scores low in them.
How is Category Impact Calculated?
For each category, its impact is calculated using this formula:
Category Impact = Total Possible Points in Category ÷ Total Possible Points in Grader
This ensures that Category Impact is based on the grader’s structure, not just the user’s performance.
How Do We Determine High, Medium, or Low Impact?
After calculating impact for all categories, they are ranked from highest to lowest and divided into three groups:
- High Impact → Top 33% of categories
- Medium Impact → Middle 33%
- Low Impact → Bottom 33%
If the number of categories is not perfectly divisible by three, extra categories are assigned as follows:
- If 1 extra category, it is added to Low.
- If 2 extra categories, one category moves from Low to Medium and the extra category is added to Low.
- If two or more categories have the same impact at a boundary, all tied categories are placed in the lower group.
Example
Let’s say a grader has six categories with these impact values:
| Category |
Impact Value |
| A |
0.40 |
| B |
0.30 |
| C |
0.20 |
| D |
0.15 |
| E |
0.10 |
| F |
0.5 |
Step 1: Rank from Highest to Lowest
- A (0.40)
- B (0.30)
- C (0.20)
- D (0.15)
- E (0.10)
- F (0.05)
Step 2: Divide into Three Equal Groups
- High Impact (Top 2 categories): A (0.40), B (0.30)
- Medium Impact (Middle 2 categories): C (0.20), D (0.15)
- Low Impact (Bottom 2 categories): E (0.10), F (0.05)
What If the Number of Categories Isn’t Divisible by 3?
If there are extra categories, they are assigned as follows:
- If 1 extra category, it is added to Low.
- If 2 extra categories, one category is moved from Low to Medium and the extra category is added to Low.
- If multiple categories are tied at a boundary, all tied categories go into the lower group.
What If the Grader Only Has One or Two Categories?
If a grader has only two categories, the impact levels are adjusted as follows:
- If the impact values are far apart, they are assigned High & Low.
- If the impact values are close, they are assigned High & Medium or Medium & Low.
- Closeness Threshold → If the difference is small enough, they are assigned Medium instead of forcing High & Low.
If a grader has only one category, the single category is always High.
Why Does Category Impact Matter?
Understanding Category Impact helps you focus on the most influential areas in a grader. High Impact categories contribute the most to the final grade, so they may deserve extra attention.
