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Properties of Model Errors in Logistic Regression and Their Application to Detect Outliers in Child Mortality Study


Author(s) : Tsirizani Mwalimu Kaombe
Emerging Topics in Statistics and Biostatistics

Abstract


The logistic regression model is commonly used in biomedical research to analyze binary outcome data. However, its assumptions have not been widely studied, which limits the post-estimation analysis of the model. This chapter explores the properties of the error term in logistic regression using mathematical and numerical techniques. The results from a simulation study showed that the error term of the model has a trimodal standard logistic probability distribution with a mean of zero and a variance between 0 and 1. The distribution is continuous and bounded below at \(-1\) and above at \(+1\). By utilizing these properties in the analysis of child mortality data in Malawi, seven outlier children were identified in the model. These children experienced death despite being in low-risk groups, such as having well-educated mothers, and a birth interval of over 36 months. The observed model properties provide a clear basis for conducting post-estimation analyses, such as detecting outlier observations in the model.


Original language en
Pages (from-to) 247-281
Publication status Published - 2025