Comparative Evaluation of Residual Diagnostic Measures for Outlier Detection in Linear Regression: An Empirical Study Using Heart Rate Data
Reg No: 410
DOI:
https://doi.org/10.56450/JEFI.2025.v3i2Suppl.084Keywords:
Outlier detection linear regression residual diagnosticsAbstract
Outliers in medical datasets can substantially distort regression models, leading to biased estimates and unreliable clinical inferences. This study evaluated residual-based diagnostic methods-including standardized residuals, Cook's Distance, DFFITS, DFBETAS, Covariance Ratio, and standardized scores-for detecting influential observations in a simple linear regression model. Using age as the predictor and heart rate as the outcome, data from 30 individuals were analyzed. The initial model (R² = 0.22) revealed one highly influential outlier (heart rate = 290 at age 42), consistently identified across multiple diagnostics. Removal of this case improved model adequacy, yielding a more stable regression (R² = 0.10) with no further significant outliers detected. Findings highlight that even a single outlier can markedly distort regression-based conclusions, underscoring the importance of employing complementary diagnostic tools to ensure valid statistical inference in medical research.
Downloads
References
Aggarwal, C. C., & Yu, P. S. (2001). Outlier detection for high dimensional data.Proceedings of the 2001 ACM SIGMOD International Conference on
Management of Data, 37-46. DOI: 10.1145/375663.375668
Barnett, V., & Lewis, T. (1994). Outliers in clinical data: Detection and treatment. Journal of Clinical Epidemiology, 47(8), 947-959.
C. C. Aggarwal, "Outlier detection in graphs and networks" in Outlier analysis, Springer, pp. 369-397, 2017.
David L. Donoho. Miriam Gasko. "Breakdown Properties of Location Estimates Based on Halfspace Depth and Projected Outlyingness." Ann.
Statist. 20 (4) 1803 - 1827, December, 1992. https://doi.org/10.1214/aos/1176348890
Downloads
Published
Issue
Section
License
Copyright (c) 2025 Dr Shashank Kirti (Author)

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
You are free to:
- Share — copy and redistribute the material in any medium or format
- The licensor cannot revoke these freedoms as long as you follow the license terms.
Under the following terms:
- Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
- NonCommercial — You may not use the material for commercial purposes.
- NoDerivatives — If you remix, transform, or build upon the material, you may not distribute the modified material.
- No additional restrictions — You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits.
Notices:
You do not have to comply with the license for elements of the material in the public domain or where your use is permitted by an applicable exception or limitation.
No warranties are given. The license may not give you all of the permissions necessary for your intended use. For example, other rights such as publicity, privacy, or moral rights may limit how you use the material.