Skip Content
You are currently on the new version of our website. Access the old version .

Stats, Volume 8, Issue 3

2025 September - 35 articles

Cover Story: A Markov chain Monte Carlo (MCMC)-based Bayesian methodology is proposed and applied to the phase-type aging model (PTAM), with a view to improving parameter estimability. The proposed method provides two methodological extensions based on an existing MCMC inference method. First, we propose a two-level MCMC sampling scheme that is applicable to scenarios where the posterior distributions do not take simple forms after data augmentation. Secondly, an existing data augmentation technique for Bayesian inference on continuous phase-type distributions is further developed in order to incorporate left-truncated data. The proposed methodology improves parameter estimability via sound prior distributions and may also be utilized as a stand-alone statistical model-fitting technique. View this paper
  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list .
  • You may sign up for email alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.

Articles (35)

  • Article
  • Open Access
735 Views
9 Pages

18 September 2025

The augmented logistic regression proposed by Diaz-Quijano directly provides risk ratios with an augmented dataset with the pseudo-observations. However, the standard errors of regression coefficients cannot be accurately estimated using either the o...

  • Article
  • Open Access
953 Views
15 Pages

A Mixture Model for Survival Data with Both Latent and Non-Latent Cure Fractions

  • Eduardo Yoshio Nakano,
  • Frederico Machado Almeida and
  • Marcílio Ramos Pereira Cardial

13 September 2025

One of the most popular cure rate models in the literature is the Berkson and Gage mixture model. A characteristic of this model is that it considers the cure to be a latent event. However, there are situations in which the cure is well known, and th...

  • Article
  • Open Access
1,162 Views
27 Pages

12 September 2025

This paper introduces the Unit-Modified Weibull (UMW) distribution, a novel probability model defined on the unit interval (0, 1). We derive its key statistical properties and estimate its parameters using the maximum likelihood method. The perf...

  • Review
  • Open Access
1,172 Views
20 Pages

Statistical Tools Application for Literature Review: A Case on Maintenance Management Decision-Making in the Steel Industry

  • Nuno Miguel de Matos Torre,
  • Valerio Antonio Pamplona Salomon and
  • Luis Ernesto Quezada

12 September 2025

Literature review plays a crucial role in research. This paper explores bibliometrics, which utilize statistical tools to evaluate the researcher’s scientific contributions. Its intent is to map frequently cited articles and authors, identify t...

  • Article
  • Open Access
831 Views
23 Pages

Bootstrap Methods for Correcting Bias in WLS Estimators of the First-Order Bifurcating Autoregressive Model

  • Tamer Elbayoumi,
  • Mutiyat Usman,
  • Sayed Mostafa,
  • Mohammad Zayed and
  • Ahmad Aboalkhair

5 September 2025

In this study, we examine the presence of bias in weighted least squares (WLS) estimation within the context of first-order bifurcating autoregressive (BAR(1)) models. These models are widely used in the analysis of binary tree-structured data, parti...

  • Article
  • Open Access
533 Views
18 Pages

27 August 2025

A standard approach for assessing the performance of partition models is to create synthetic datasets with a prespecified clustering structure and assess how well the model reveals this structure. A common format involves subjects being assigned to d...

  • Article
  • Open Access
1,502 Views
22 Pages

27 August 2025

The phase-type aging model (PTAM) belongs to a class of Coxian-type Markovian models that can provide a quantitative description of well-known aging characteristics that are part of a genetically determined, progressive, and irreversible process. Due...

  • Article
  • Open Access
653 Views
16 Pages

25 August 2025

This paper describes a region-oriented method of pattern classification based on the Cartesian system model (CSM), a mathematical model that allows manipulating mixed feature-type symbolic data. We use the supervised hierarchical conceptual clusterin...

  • Communication
  • Open Access
958 Views
20 Pages

24 August 2025

The aim of this research is to provide a 25-year multi-model analysis of gender dynamics in economics articles that include at least one Romanian-affiliated author, published in Web of Science journals between 2000 and 2025 (2025 records current as o...

  • Article
  • Open Access
1 Citations
1,512 Views
16 Pages

18 August 2025

Change-point models are frequently considered when modeling phenomena where a regime shift occurs at an unknown time. In aging research, these models are commonly adopted to estimate of the onset of cognitive decline. Yet these models present several...

  • Article
  • Open Access
895 Views
13 Pages

A Mixture Integer GARCH Model with Application to Modeling and Forecasting COVID-19 Counts

  • Wooi Chen Khoo,
  • Seng Huat Ong,
  • Victor Jian Ming Low and
  • Hari M. Srivastava

13 August 2025

This article introduces a flexible time series regression model known as the Mixture of Integer-Valued Generalized Autoregressive Conditional Heteroscedasticity (MINGARCH). Mixture models provide versatile frameworks for capturing heterogeneity in co...

  • Communication
  • Open Access
3 Citations
1,156 Views
9 Pages

13 August 2025

In repeated-measures meta-analyses, raw data are often unavailable, preventing the calculation of the correlation coefficient r between pre- and post-intervention values. As a workaround, many researchers adopt a heuristic approximation of r = 0.7. H...

  • Article
  • Open Access
716 Views
27 Pages

Individual Homogeneity Learning in Density Data Response Additive Models

  • Zixuan Han,
  • Tao Li,
  • Jinhong You and
  • Narayanaswamy Balakrishnan

9 August 2025

In many complex applications, both data heterogeneity and homogeneity are present simultaneously. Overlooking either aspect can lead to misleading statistical inferences. Moreover, the increasing prevalence of complex, non-Euclidean data calls for mo...

  • Article
  • Open Access
1,180 Views
33 Pages

6 August 2025

Penalized regression methods are widely used for variable selection. Non-negative garrote (NNG) was one of the earliest methods to combine variable selection with shrinkage of regression coefficients, followed by lasso. About a decade after the intro...

  • Review
  • Open Access
1 Citations
1,446 Views
19 Pages

Archimedean Copulas: A Useful Approach in Biomedical Data—A Review with an Application in Pediatrics

  • Giulia Risca,
  • Stefania Galimberti,
  • Paola Rebora,
  • Alessandro Cattoni,
  • Maria Grazia Valsecchi and
  • Giulia Capitoli

1 August 2025

Many applications in health research involve the analysis of multivariate distributions of random variables. In this paper, we review the basic theory of copulas to illustrate their advantages in deriving a joint distribution from given marginal dist...

  • Article
  • Open Access
2,868 Views
22 Pages

Automated Classification of Crime Narratives Using Machine Learning and Language Models in Official Statistics

  • Klaus Lehmann,
  • Elio Villaseñor,
  • Alejandro Pimentel,
  • Javiera Preuss,
  • Nicolás Berhó,
  • Oswaldo Diaz and
  • Ignacio Agloni

30 July 2025

This paper presents the implementation of a language model–based strategy for the automatic codification of crime narratives for the production of official statistics. To address the high workload and inconsistencies associated with manual codi...

  • Article
  • Open Access
2,962 Views
22 Pages

22 July 2025

In observational causal inference studies, unmeasured confounding remains a critical threat to the validity of effect estimates. While proximal causal inference (PCI) has emerged as a powerful framework for mitigating such bias through proxy variable...

  • Article
  • Open Access
1,120 Views
17 Pages

Machine Learning Ensemble Algorithms for Classification of Thyroid Nodules Through Proteomics: Extending the Method of Shapley Values from Binary to Multi-Class Tasks

  • Giulia Capitoli,
  • Simone Magnaghi,
  • Andrea D'Amicis,
  • Camilla Vittoria Di Martino,
  • Isabella Piga,
  • Vincenzo L'Imperio,
  • Marco Salvatore Nobile,
  • Stefania Galimberti and
  • Davide Paolo Bernasconi

16 July 2025

The need to improve medical diagnosis is of utmost importance in medical research, consisting of the optimization of accurate classification models able to assist clinical decisions. To minimize the errors that can be caused by using a single classif...

  • Communication
  • Open Access
1 Citations
3,786 Views
30 Pages

15 July 2025

The increasing complexity of financial reporting has enabled the implementation of innovative accounting practices that often obscure a company’s actual performance. This project seeks to uncover manipulative behaviours by constructing an anoma...

  • Article
  • Open Access
3 Citations
1,020 Views
23 Pages

The Extended Kumaraswamy Model: Properties, Risk Indicators, Risk Analysis, Regression Model, and Applications

  • Morad Alizadeh,
  • Gauss M. Cordeiro,
  • Gabriela M. Rodrigues,
  • Edwin M. M. Ortega and
  • Haitham M. Yousof

14 July 2025

We propose a new unit distribution, study its properties, and provide an important application in the field of geology through a set of risk indicators. We test its practicality through two applications to real data, make comparisons with the well-kn...

  • Article
  • Open Access
777 Views
10 Pages

14 July 2025

Standard asymptotic inference for proportional hazards models is conventionally performed by calculating a standard error for the estimate and comparing the estimate divided by the standard error to a standard normal distribution. In this paper, we c...

  • Article
  • Open Access
1,644 Views
17 Pages

The Detection Method of the Tobit Model in a Dataset

  • El ouali Rahmani and
  • Mohammed Benmoumen

12 July 2025

This article proposes an extension of detection methods for the Tobit model by generalizing existing approaches from cases with known parameters to more realistic scenarios where the parameters are unknown. The main objective is to develop detection...

  • Article
  • Open Access
1,049 Views
16 Pages

Quantile Estimation Based on the Log-Skew-t Linear Regression Model: Statistical Aspects, Simulations, and Applications

  • Raúl Alejandro Morán-Vásquez,
  • Anlly Daniela Giraldo-Melo and
  • Mauricio A. Mazo-Lopera

11 July 2025

We propose a robust linear regression model assuming a log-skew-t distribution for the response variable, with the aim of exploring the association between the covariates and the quantiles of a continuous and positive response variable under skewness...

  • Article
  • Open Access
1 Citations
1,265 Views
14 Pages

Well Begun Is Half Done: The Impact of Pre-Processing in MALDI Mass Spectrometry Imaging Analysis Applied to a Case Study of Thyroid Nodules

  • Giulia Capitoli,
  • Kirsten C. J. van Abeelen,
  • Isabella Piga,
  • Vincenzo L’Imperio,
  • Marco S. Nobile,
  • Daniela Besozzi and
  • Stefania Galimberti

10 July 2025

The discovery of proteomic biomarkers in cancer research can be effectively performed in situ by exploiting Matrix-Assisted Laser Desorption Ionization (MALDI) Mass Spectrometry Imaging (MSI). However, due to experimental limitations, the spectra ext...

  • Article
  • Open Access
684 Views
18 Pages

8 July 2025

Testing interval hypotheses is of huge relevance in the biomedical and cognitive sciences; for example, in clinical trials. Frequentist approaches include the proposal of equivalence tests, which have been used to study if there is a predetermined me...

  • Article
  • Open Access
585 Views
24 Pages

5 July 2025

The problem of estimating the ratio of the means of a two-component Poisson mixture model is considered, when each component is subject to zero-inflation, i.e., excess zero counts. The resulting zero-inflated Poisson mixture (ZIPM) model can be viewe...

  • Article
  • Open Access
2,646 Views
14 Pages

30 June 2025

The diagnosis-related group (DRG) system classifies patients into different groups in order to facilitate decisions regarding medical insurance payments. Currently, more than 600 standard DRGs exist in China. Payment details represented by DRG weight...

  • Article
  • Open Access
1 Citations
1,351 Views
14 Pages

28 June 2025

Imbalanced regression poses a significant challenge in real-world prediction tasks, where rare target values are prone to overfitting during model training. To address this, prior research has employed relevance functions to quantify the rarity of ta...

  • Article
  • Open Access
986 Views
14 Pages

Elicitation of Priors for the Weibull Distribution

  • Purvi Prajapati,
  • James D. Stamey,
  • David Kahle,
  • John W. Seaman,
  • Zachary M. Thomas and
  • Michael Sonksen

23 June 2025

Bayesian methods have attracted increasing interest in the design and analysis of clinical trials. Many of these clinical trials investigate time-to-event endpoints. The Weibull distribution is often used in survival and reliability analysis to model...

  • Article
  • Open Access
836 Views
27 Pages

20 June 2025

Traditional methods for mission reliability assessment under operational testing conditions exhibit some limitations. They include coarse modeling granularity, significant parameter estimation biases, and inadequate adaptability for handling heteroge...

Get Alerted

Add your email address to receive forthcoming issues of this journal.

XFacebookLinkedIn
Stats - ISSN 2571-905X