Enter any three values (Average Grade, Standard Deviation, Class Average, or R Score) into the calculator to determine the missing one. This calculator uses a simplified “R Score” defined as a shifted Z-score (Z + 5) based on a single class’s statistics.
Simplified R Score Formula (Shifted Z-Score)
The following formula is used in this calculator to compute a simplified “R Score” from a Z-score:
R = Z + 5
Where:
- R is the R Score
- Z is the Z-Score, calculated as (Average Grade − Class Average) / Standard Deviation
To calculate this R Score, first determine the Z-Score using the student's average grade, the class average, and the standard deviation. Then add 5 to the Z-Score to shift the scale so that a Z-score of 0 corresponds to an R Score of 5.
Important: This simplified R Score is not the official Quebec/CEGEP cote R, which uses additional factors (such as group strength and other adjustments) and therefore cannot be computed from only these three class statistics.
What is an R Score?
On this page, “R Score” refers to a simple standardized score based on a Z-score, shifted by 5 points (R = Z + 5). It indicates how far a student’s grade is above or below the class average in units of the class standard deviation. This can help compare performance within the same class or between classes only when grading scales and distributions are meaningfully comparable.
How to Calculate an R Score?
The following steps outline how to calculate the simplified R Score shown in this calculator:
- First, determine the student's average grade.
- Next, determine the class average grade.
- Then, determine the standard deviation of the class grades.
- Calculate the Z-Score using the formula: Z = (Average Grade − Class Average) / Standard Deviation.
- Add 5 to the Z-Score to get the R Score: R = Z + 5.
- Use the calculator above to verify your calculations.
Example Problem:
Use the following variables as an example problem to test your knowledge:
Average Grade = 85%
Class Average = 75%
Standard Deviation = 10 (percentage points)
Z = (85 − 75) / 10 = 1
R = Z + 5 = 1 + 5 = 6
