A unified exponential-H family for modeling real-life data: Properties and inference

Heliyon. 2024 Mar 12;10(6):e27661. doi: 10.1016/j.heliyon.2024.e27661. eCollection 2024 Mar 30.

Abstract

The exponential distribution is one of the most widely used statistical distribution for reliability issues. In this paper, we introduce a novel family based on the exponential model, called the new exponential-H (NEx-H) family. The sub-models of the NEx-H family are capable of accommodating variable failure rates, as well as unimodal, bimodal, left-skewed, symmetric, right-skewed, and J-shape densities. The mathematical features of the NEx-H family are derived. The parameters of the NEx-Weibull distribution are estimated by using seven estimation methods. Detailed numerical simulations are presented. Based on our study, the maximum likelihood is the best estimation method for estimating the NEx-Weibull parameters. Three real-life data sets are fitted using the NEx-Weibull distribution. The NEx-Weibull model provides better fit as compared to some competing Weibull models.

Keywords: Bathtub hazard rate; Bimodal data; Entropy; Estimation methods; Order statistics; Weibull distribution.