The deviation method for evaluating judges
Deviation is the IFBB’s official tool for assessing how closely each judge matches the final result. The smaller the sum of deviations, the better the judge. The IFBB adopted the method starting with the 1997 World Championships.
What is the deviation method and why is it needed?
At bodybuilding competitions, results are decided by a panel of judges, not by a single person. This means that one judge’s subjectivity should carry less weight overall. But how do you know whether a particular judge systematically strays from the rest? That is exactly what judge assessment is for.
The method starts from a simple premise: the ideal judge makes no mistakes at all. The places they award match the panel’s final result exactly. The more an individual judge differs from the final result, the greater their deviation and the lower their accuracy percentage.
The deviation method: how the scoring works
For each judge, the places they awarded are compared with the final result. The difference, whether positive or negative, is counted as one deviation. Then all the deviations are added together.
The accuracy percentage is calculated as follows: the sum of the possible individual places minus the sum of deviations, divided by the sum of the possible places. With six competitors, the sum of the possible individual places is 21 (i.e. 1+2+3+4+5+6=21).
Example for Judge A:
| Final result | Judge A | Deviation |
|---|---|---|
| 1. | 1. | 0 |
| 2. | 3. | 1 |
| 3. | 5. | 2 |
| 4. | 6. | 2 |
| 5. | 2. | 3 |
| 6. | 4. | 2 |
Judge A’s sum of deviations is 10. Accuracy percentage: 21 minus 10 = 11; 11 divided by 21 = 52.4%. The judges’ exam requires an accuracy of at least 70%. Judge A failed this exam.
Judge accuracy at the 2006 Estonian Cup
It is interesting to see how the sum of deviations works in real life. At the 2006 Estonian Cup, three categories were analyzed: women’s bodyfitness (6 competitors), juniors +72.5 kg (7 competitors) and the men’s overall category (5 competitors). There is no point in running the calculation for categories with only two or three competitors, because the statistics become too random.
| Judge | BF | J +72.5 | ABS. | Average |
|---|---|---|---|---|
| Judge 1. Oleg Andla | 72 | 93 | 73 | 79 |
| Judge 2. Fred Antson | 81 | 79 | 100 | 86 |
| Judge 3. Tanel Toomela | 100 | 79 | 100 | 93 |
| Judge 4. Kaja Tuisk | 95 | 64 | 73 | 77 |
| Judge 5. Andres Lepp | 62 | 100 | 87 | 83 |
| Judge 6. Jevgeni Selnihhin | 33 | 93 | 87 | 71 |
| Judge 7. Indrek Otsus | 90 | 93 | 100 | 94 |
All seven judges cleared the required 70% threshold, although their averages varied quite a bit, from 71 to 94. Tanel Toomela and Indrek Otsus showed the highest average accuracy, while Jevgeni Selnihhin received the lowest average, 71, which is the closest to the required threshold.
FAQ: the deviation method
When did the IFBB start using the deviation method?
The IFBB adopted the method starting with the 1997 World Championships. Before that, there was no standardized way to measure judges’ accuracy.
What accuracy percentage is required in the judges’ exam?
The judges’ exam requires an accuracy of at least 70%. Anything below that means the judge has strayed too far from the final result and does not meet the standard.
Why are categories with only two or three competitors not counted?
In categories with few participants, deviations are statistically unreliable, because a single wrong place affects the final result too much. The method gives a reliable picture from four to five competitors in a category.
Author: Indrek Otsus, EKFL Secretary General
Come and train! ArtGym
