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Condition Index/Evidence
Method evidence record

Condition Index

The Condition Index, introduced by Belsley, Kuh, and Welsch (1980), is a scalar measure derived from singular value decomposition of the scaled regressor matrix. It quantifies the degree of near-linear dependence among predictors in ordinary least squares regression, enabling analysts to detect collinearity that inflates coefficient variance and destabilises parameter estimates. Widely used in economics, social sciences, and biomedical research wherever OLS regression is applied.

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Condition Index (Belsley Collinearity Diagnostics)
Taxonomic method record · regression-model / econometrics
  • Belsley, D. A., Kuh, E., & Welsch, R. E. (1980). Regression Diagnostics: Identifying Influential Data and Sources of Collinearity. John Wiley & Sons. · ISBN 978-0-471-05856-4
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Related methods

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Same method familyOLS Regressionmachine-suggested · Relational suggestion, not evidence.Taxonomic bucketVariance Inflation Factormachine-suggested · Relational suggestion, not evidence.

Evidence status

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Sources

1 recorded citation, copied from the method source record.

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