Disparate Impact
Calculate selection-rate disparity against a caller-supplied ratio threshold.
Description
Selection-rate disparity compares group shares under a supplied ratio criterion.
Selection-rate disparity compares group shares under a supplied ratio criterion. Context and statistical evidence govern interpretation.1
Calculate selection-rate disparity against a caller-supplied ratio threshold.
When to use Disparate Impact
Use this tool to calculate selection-rate disparity against a caller-supplied ratio threshold.
Prepare the documented facts, aligned totals or expected/observed evidence labels requested. Choose applicable requirements and thresholds separately before interpreting a planning screen.
How to use Disparate Impact and understand its results
- Prepare the documented facts, aligned totals or expected/observed evidence labels requested. Choose applicable requirements and thresholds separately before interpreting a planning screen.
- Enter protectedGroupSelected, protectedGroupTotal, referenceGroupSelected, referenceGroupTotal, minimumRateRatio using the field table and calculation rules, then run the tool.
- Read protectedSelectionRate, referenceSelectionRate, rateRatio, belowThreshold. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| protectedGroupSelected | Protected-group selections | integer; minimum: 0 | Required |
| protectedGroupTotal | Protected-group population | integer; minimum: 0 | Required |
| referenceGroupSelected | Reference-group selections | integer; minimum: 0 | Required |
| referenceGroupTotal | Reference-group population | integer; minimum: 0 | Required |
| minimumRateRatio | Minimum acceptable rate ratio | number; minimum: 0 | Required |
Enter positive integer totals, selected counts within totals, positive reference selection and nonnegative minimum. Return fractions/ratio/strict below flag.
ratio=(protectedSelected/total)/(referenceSelected/total) Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| protectedSelectionRate | Protected-group selection rate | number; minimum: 0; maximum: 1 |
| referenceSelectionRate | Reference-group selection rate | number; minimum: 0; maximum: 1 |
| rateRatio | Selection-rate ratio | number; minimum: 0 |
| belowThreshold | Below supplied ratio threshold | boolean |
{
"input": {
"protectedGroupSelected": 40,
"protectedGroupTotal": 100,
"referenceGroupSelected": 50,
"referenceGroupTotal": 100,
"minimumRateRatio": 0.8
},
"output": {
"protectedSelectionRate": 0.4,
"referenceSelectionRate": 0.5,
"rateRatio": 0.8,
"belowThreshold": false
}
}Limitations and assumptions
No discrimination, causality, significance or legal adverse-impact conclusion is established.
Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.
Alternative or Complementary methods
Use Alert-Threshold Tuning: Measure continuous-audit alert precision, recall, and false positives. For a complementary task, use Committee Self-Evaluation: Score an audit-committee self-evaluation against a supplied minimum.
References
-
Disparate Impact — tool.io
Similar or alternative tools
- Alert-Threshold Tuning
Measure continuous-audit alert precision, recall, and false positives.
- Committee Self-Evaluation
Score an audit-committee self-evaluation against a supplied minimum.