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Sampling Bias

Bias Types

Classification

Data Governance and Ethics

Overview

Sampling bias occurs when the data collected for training, testing, or validating an AI system is not representative of the intended population or use context. This bias can arise from over-representing certain groups, under-representing others, or systematically excluding subsets of data. For example, if a facial recognition system is trained primarily on Western-centric datasets, it may perform poorly on individuals from other regions or ethnicities. Sampling bias can lead to inaccurate, unfair, or unsafe AI outcomes, undermining system reliability and trustworthiness. While techniques such as stratified sampling and data augmentation can mitigate bias, complete elimination is challenging due to practical constraints like data availability, privacy, and cost. Moreover, subtle or intersectional biases may persist undetected, making ongoing monitoring essential.

Governance Context

AI governance frameworks such as the EU AI Act and NIST AI Risk Management Framework require organizations to identify, assess, and mitigate data bias risks, including sampling bias. Specific obligations include conducting bias impact assessments, documenting dataset composition, and implementing controls for diverse data sourcing. The EU AI Act mandates high-risk AI systems to ensure training, validation, and testing datasets are relevant, representative, free of errors, and as complete as possible. Similarly, ISO/IEC 24028:2020 recommends regular audits of dataset representativeness and the implementation of corrective measures where bias is detected. Concrete obligations include (1) performing documented bias impact assessments before deployment and (2) maintaining transparent records of dataset sourcing and composition. Controls may also include ongoing dataset audits and corrective action protocols. Failure to address sampling bias can result in regulatory penalties, reputational harm, and legal liability.

Ethical & Societal Implications

Sampling bias can exacerbate existing inequalities, leading to unfair treatment, exclusion, and harm to under-represented groups. Ethically, it raises questions of justice, accountability, and transparency in AI deployment. Societal trust in AI systems may erode if outcomes are perceived as biased or discriminatory. Addressing sampling bias is crucial not only for legal compliance but also for upholding human rights and fostering social cohesion. Furthermore, the persistence of sampling bias can undermine the legitimacy of automated decision-making and perpetuate systemic injustices.

Key Takeaways

Sampling bias undermines the fairness and reliability of AI systems.; Governance frameworks mandate proactive identification and mitigation of sampling bias.; Ongoing dataset audits and impact assessments are essential for compliance.; Failure to address sampling bias can result in legal, ethical, and reputational risks.; Mitigation strategies include diverse data sourcing, transparent documentation, and continuous monitoring.; Concrete obligations include bias impact assessments and maintaining records of dataset composition.

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