Decision Framing and Measurement · Lesson 2

Data Quality and Measurement Bias

11 min read

Lesson objectives

  • Evaluate measuring decision fitness through completeness, accuracy, timeliness and representation and issue a reviewable conditional decision.

A fictional lender reviews 18,000 records with an eleven-percent default rate; cash-flow data are missing in twenty-three percent of records across four regions.

Decision-grade data must measure the intended construct, arrive at the right time and represent the population in which the action will be used. Complete rows alone do not establish validity because missingness may itself be related to default.

Create a card for each field that records origin, definition, timestamp, missing rate, missingness mechanism and expected regional effect. Compare complete and missing records before deletion or imputation, and distinguish measurement error from population difference.

A missingness indicator does not automatically remove causal bias and can proxy for region or group. Constrain or exclude the field when error cannot be explained or disparity persists.

Create a card for each field that records origin, definition, timestamp, missing rate, missingness mechanism and expected regional effect. Compare complete and missing records before deletion or imputation, and distinguish measurement error from population difference.

Missing records equal 18,000×0.23=4,140, while expected defaults total about 1,980. If default is eighteen percent among missing records and nine percent among complete records, complete-case deletion understates risk and changes who reaches review.

Do not deploy the field unchanged. Compare a model without it with a documented imputation path that includes a missingness indicator, then inspect calibration and harm by region.

A missingness indicator does not automatically remove causal bias and can proxy for region or group. Constrain or exclude the field when error cannot be explained or disparity persists.

Lesson summary

Advanced application of measuring decision fitness through completeness, accuracy, timeliness and representation in a realistically constrained decision.