Official NHA Assessment
Race 2: 4RACING.TV DERBY PLATE (3 year olds)
Line Horse
Zatara Magic
Reference for assessment
Exact Matches
0 / 6
Calculated = Official
Close Matches
0 / 6
Within 2 points
Significant Diffs
5 / 6
More than 5 points
Detailed Assessment
------------------------------------------------------------------------------------------------------------------------ Pos Horse Age Weight Fin Lengths WFA Pre Race Rating New Adj ------------------------------------------------------------------------------------------------------------------------ 1 Heathcliff 2 56.0 1 0.00 0.0 86 90 90 +4 2 Zatara Magic 5 54.0 2 1.50 0.0 91 91 91 +0 3 Perfection 3 60.0 3 2.50 3.5 103 95 95 -8 4 Quasimodo 2 56.0 4 2.75 0.0 80 93 93 +13 5 Matsuyamo 2 56.0 5 3.00 0.0 75 93 93 +18 6 Indy View 2 54.0 6 13.25 0.0 79 86 86 +7 ------------------------------------------------------------------------------------------------------------------------
Horse-by-Horse Comparison
| Pos | Horse | Pre-Rating | Official New | Calculated | Discrepancy | WFA (kg) | Line Horse | Calculation |
|---|---|---|---|---|---|---|---|---|
| 1 | Heathcliff | 86 | 100 | 90 | +10 | 0.0 | - | |
| 2 | Zatara Magic Line | 91 | 114 | 91 | +23 | 0.0 | ||
| 3 | Perfection | 103 | 103 | 95 | +8 | 3.5 | - | |
| 4 | Quasimodo | 80 | 89 | 93 | -4 | 0.0 | - | |
| 5 | Matsuyamo | 75 | 78 | 93 | -15 | 0.0 | - | |
| 6 | Indy View | 79 | 76 | 86 | -10 | 0.0 | - |
Assessment Methodology
Calculation Steps:
- Identify Line Horse - consistent performer used as reference
- Calculate WFA Allowance based on age, distance, and month
- Apply Drag Adjustment for beaten margin
- Calculate Actual Weight Performance:
Weight - Drag - WFA - Compare to Line Horse to determine race rating
- Apply special rules (maiden caps, layoff allowance)
Key Formulas:
- Drag Effect: Varies by distance (see Benchmarks page)
- 1 length ≈ 1kg at 1 mile (1600m)
- WFA Scale: Based on Admiral Rous's 1855 table
- Rating Points: 1kg = 2 rating points