In this study, a variant of the generalized Chen (GC) distribution with parameters α, β, γ, δ, and λ, termed the Modified Generalized Chen (MGC) distribution, was introduced. The study evaluated several Chen distribution variants theoretically, focusing on the MGC distribution. Variants considered include the Generalized Chen (GC), Half-Cauchy Chen (HCC), New Extended Chen (NEC), and Exponentially Generalized Modified Chen (EGMC) distributions. The objectives of the study was to derive the probability density function (PDF) and cumulative density function (CDF) of the MGC distribution, determine its statistical properties and reliability characteristics, compare these properties and characteristics to existing distributions, and empirically evaluate its performance. The study developed unique expressions for the PDF, CDF, survival function, and hazard function of the MGC distribution. By evaluating PDFs and performance measures such as the Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC), and mean square error (MSE) across various datasets, the MGC distribution consistently demonstrated superiority over other variants. The MGC distribution offers improved model fit, predictive accuracy, and interpretability without sacrificing simplicity. The dataset employed in this study was the secondary data, encompassing economic indicators from 1981 to 2021 and public health expenditure data for Nigeria and Ghana from 1995 to 2014. Statistical analyses revealed that on the average, the MGC distribution outperforms others, with superior average AIC (-509.95), BIC (-510.49), and MSE (499.89) measures across the datasets considered in the study. This superior performance indicates better fit and accuracy in predicting economic and public health outcomes, offering valuable insights for policymakers and researchers. The study underscores the importance of adopting flexible and interpretable distribution models like the MGC distribution to enhance empirical analyses, inform policy decisions, and advance knowledge in econometrics and related disciplines.
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