AUC Statistic
Definition
Area under the receiver operating characteristic curve; the standard criterion-validity metric for forensic risk and malingering instruments, with 0.70 considered a minimum adequate level.
- Full name
- Area under the receiver operating characteristic curve
- Use
- Criterion-validity metric for risk and malingering instruments
- Minimum adequate level
- Around 0.70
- Chance baseline
- 0.50
Common questions
How is the AUC statistic used to evaluate a malingering test rather than a violence risk tool?+
The same logic applies: the AUC reflects how well the instrument's scores separate confirmed malingerers from genuine responders in a validation sample, regardless of whether the outcome being predicted is future violence or feigned symptoms.
Why is a threshold like 0.70 treated as a minimum rather than a target?+
An AUC near 0.70 shows the instrument performs meaningfully better than chance but still misclassifies a substantial share of cases, so evaluators use it as a floor for acceptable evidentiary use, not as evidence the tool is highly accurate.
Related terms
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- Criterion Validity
- The degree to which test scores predict or correlate with an external criterion; predictive criterion validity is most relevant to forensic instruments.
- Daubert Standard
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- Ecological Validity
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- Reliability
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- Validity
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