Journal of the Operational Research Society

, Volume 65, Issue 3, pp 408–415 | Cite as

Selection bias in credit scorecard evaluation

Special Issue Paper

Abstract

Selection bias is a perennial problem when constructing and evaluating scorecards. It is familiar in the context of reject inference, but crops up in many other situations as well. In this paper, we examine the impact of how accepting or rejecting customers using one scorecard leads to biased comparisons of performance between that scorecard and others. This has important implications for organisations seeking to improve or replace scorecards.

Keywords

credit scoring Kolmogorov–Smirnov statistic area under the ROC curve selection bias 

Notes

Acknowledgements

We are grateful to the UK bank that provided the UPL data for the real example, and to the anonymous referees for deep and helpful comments.

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Copyright information

© Operational Research Society Ltd. 2013

Authors and Affiliations

  1. 1.Department of MathematicsImperial College LondonLondonUK
  2. 2.Heilbronn Institute for Mathematical Research, University of BristolBristolUK

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