Topic 11 of 20 · Part III : Personalisation and Responsible AI

Bias and fairness

Bias in a financial AI system often begins with uneven data representation : abundance mistaken for quality.

The control pattern

Data asset

Representation in training, retrieval and evaluation data

Knobs

Group balance, Market coverage, Labels, Peer definitions, Counterfactual examples, Weighting

Outcome

More equitable and less systematically distorted behaviour

Measurement

See how to measure this below

What it is

Bias in a financial AI system often begins with uneven data representation. Large, heavily covered companies produce more news, analyst research, transcripts and clean structured data than small or international firms. If that abundance is mistaken for quality, the assistant may consistently favour popular securities or sectors.

Representation is therefore the data asset to change. The knobs include company size, sector, geography, reporting style, language, exchange, analyst coverage, and whether failed or delisted companies remain in historical data.

Fairness does not require identical scores across unlike companies. It requires comparable evidence, defensible peer definitions and consistent rules.

The knobs in detail

Each row is one adjustable property of the data asset, and what moving it tends to do.

KnobWhat you adjustLikely effect
Group balanceRepresentation across segmentsStops abundance masquerading as quality
Market coverageSize, geography, exchange, languageControls where the system is reliable
LabelsHow ground truth is definedEncodes assumptions into every score
Peer definitionsWho a company is compared againstA misdefined peer group is a fairness failure
Counterfactual examplesSame fundamentals, different name or sectorReveals unwanted preference
WeightingEmphasis across segments in trainingCorrects systematic under-representation

Applied: Stocks Assistant

Stocks Assistant should evaluate extraction and scoring across market-cap bands, industries, business models and reporting conventions. Peer groups are themselves a fairness knob: comparing a bank's leverage with a software company's leverage produces a misleading score, as does applying one profitability threshold across capital-intensive and asset-light industries. Counterfactual tests can hold fundamentals constant while changing names, sector labels or popularity indicators. Historical backtests must control survivorship bias by including firms that merged, failed or left an index.

How to measure it

Evidence that the knob produced the intended behaviour, rather than shifting the problem elsewhere.

  • Data coverage and missingness by segment
  • Error rates and calibration by segment
  • Ranking exposure across market-cap bands and sectors
  • Counterfactual sensitivity to name and sector labels

Common mistakes

Turning data scarcity into a negative investment judgment. Show lower confidence instead.

Backtests that quietly exclude companies that failed or were delisted.