Asian Journal of Probability and Statistics
https://www.journalajpas.com/index.php/AJPAS
<p style="text-align: justify;"><strong>Asian Journal of Probability and Statistics</strong> <strong>(ISSN: <a href="https://nsl.niscpr.res.in/ISSNPROCESS/issnassignedinfo.jsp">2582-0230</a>) </strong>aims to publish high-quality papers (<a href="https://journalajpas.com/index.php/AJPAS/general-guideline-for-authors">Click here for Types of paper</a>) in all areas of ‘Probability and Statistics’. By not excluding papers based on novelty, this journal facilitates the research and wishes to publish papers as long as they are technically correct and scientifically motivated. The journal also encourages the submission of useful reports of negative results. This is a quality controlled, OPEN peer-reviewed, open-access INTERNATIONAL journal.</p>en-US[email protected] (Asian Journal of Probability and Statistics)[email protected] (Asian Journal of Probability and Statistics)Wed, 09 Sep 2026 07:29:22 +0000OJS 3.3.0.21http://blogs.law.harvard.edu/tech/rss60Comparative Machine Learning Modeling of Self-help Groups’ Impact on Livelihoods in Murang’a East Sub-county
https://www.journalajpas.com/index.php/AJPAS/article/view/951
<p>Self-help groups are widely used within communities to mobilise savings, access credit and support income-generating activities. This study compared three machine learning techniques: Logistic Regression, Naïve Bayes and Support Vector Machine, to model wealth status among self-help group members in Murang’a East Sub-County, Kenya. Primary data were collected through structured questionnaires from 969 self-help group members included in the final analysis, drawn from a target population of 2,250 members. Principal Component Analysis identified the factors most strongly associated with self-help groups’ performance. The PCA results ranked frequency of meetings and quality of discussions as the most important factors, followed by access to financial resources and credit facilities, collaboration with other organisations and stakeholders, member participation and engagement, community support, supportive policies, training and capacity building, and leadership and management. Logistic Regression, Naïve Bayes and Support Vector Machine were then fitted to classify members according to whether their wealth status had improved since joining a self-help group. Logistic Regression achieved an accuracy of 88.04%, Naïve Bayes 92.34% and Support Vector Machine 84.62%. Naïve Bayes also recorded the highest precision (94.92%), recall (96.89%) and F1-score (95.89%). The results indicated that the choice of classification method affected predictive performance, with Naïve Bayes providing the strongest overall performance. The study contributes to knowledge of self-help groups’ role in improving rural livelihoods and reducing poverty in Kenya and makes a methodological contribution by comparing classification models for predicting members’ wealth status and demonstrating the applicability of Naïve Bayes for analysing self-help group livelihood outcomes.</p>Jane Wangui Runo, Loise Muthoni Wahome
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
https://www.journalajpas.com/index.php/AJPAS/article/view/951Wed, 09 Sep 2026 00:00:00 +0000Comparing Mathematics Students' Interest in Learning Algebra Using the Friedman Test: A Nonparametric Approach
https://www.journalajpas.com/index.php/AJPAS/article/view/952
<p><strong>Purpose:</strong> This study explored how students’ interest in learning algebra changes over time and whether teaching methods influence that interest.</p> <p><strong>Design/Methodology/Approach:</strong> The research involved ten first-year Mathematics Education students, whose interest in algebra was measured at three stages: before instruction, midway through the semester, and at the end of the course. A Likert-scale questionnaire was used to capture students’ interest, and because the same students were measured repeatedly using ordinal data, the Friedman test was applied for analysis.</p> <p><strong>Findings:</strong> The results showed a clear and significant change in interest levels, with students becoming more interested after the initial lessons and maintaining a relatively high level of interest by the end of the semester. These findings suggest that effective and engaging instruction can positively shape students’ attitudes toward algebra. The study also demonstrates that the Friedman test is a suitable and reliable method for analysing repeated interest data in mathematics education research. Finally, the result implies that students' interest in mathematics is not significantly different between the two linked groups.</p> <p><strong>Originality/Novelty:</strong> Despite its suitability, the Friedman test remains underutilized in mathematics education research, with many studies continuing to rely on parametric techniques even when data characteristics suggest otherwise.</p>Bright Asare, Yarhands Dissou Arthur, Benjamin Adu Obeng, Sadri Alija, Shadrach Mensah
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
https://www.journalajpas.com/index.php/AJPAS/article/view/952Thu, 10 Sep 2026 00:00:00 +0000Maximum Likelihood Estimation and Forecasting Performance of the GARCH Model Based on the Geometric Measure of Variation
https://www.journalajpas.com/index.php/AJPAS/article/view/953
<p>Volatility models in the GARCH family typically build the conditional scale from an arithmetic average of squared or absolute deviations, an averaging rule that is disproportionately sensitive to large shocks and, through the triangular inequality, tends to systematically overstate the true average displacement of returns. This paper studies G-GARCH(1,1), a GARCH-type model in which the conditional scale Gt is instead driven by the geometric measure of variation through the log-linear recursion ln Gt = \(\omega\) + a ln |\(\varepsilon\)t-1 | + b ln Gt-1, so that the model’s response to a shock is logarithmic rather than quadratic in its magnitude. Building on established theoretical properties of this specification, namely its stationarity, ergodicity, positivity, long-run behaviour, identifiability, and a formal bound showing that the geometric scale can never exceed the classical conditional mean absolute deviation, this paper derives the model’s maximum likelihood estimator under both Gaussian and Student’s t innovations, obtaining the score function analytically through a recursive sensitivity argument, proving that no closed-form estimator exists, establishing consistency and asymptotic normality under regularity conditions analogous to those used for the classical GARCH estimator, and supplying a constrained-to-unconstrained reparameterisation together with a Broyden–Fletcher–Goldfarb–Shanno (BFGS) estimation algorithm that enforces the stationarity restrictions automatically. We then evaluate the model empirically against four competing specifications, standard GARCH(1,1) and exponential GARCH(1,1), each under Gaussian and Student’s t innovations, across three daily return series chosen to span a range of market conditions: Safaricom PLC on the Nairobi Securities Exchange, a frontier-market single stock; Google (Alphabet Inc.) on the Nasdaq, a developed-market single stock; and the S&P 500 index, a developed-market diversified benchmark. Applied to more than four thousand daily observations per series (January 2010 to June 2026) with a held-out test window drawn from the first half of 2026, every G-GARCH parameter is estimated with high precision (p < 0.001) in every market. The standard GARCH(1,1) model with Student’s t innovations attains the best in-sample fit by both the Akaike and Bayesian information criteria in all three markets, yet ranks last or second-to-last on every out-of-sample accuracy metric examined, a pattern traced to its squared-residual score letting a handful of extreme training returns pull its estimated tail thickness toward the boundary of finite kurtosis ( \(\hat{v}\) between 3.09 and 5.32 across the three series). The G-GARCH(1,1) model with Student’s t innovations is, by contrast, the best or joint-best out-of-sample forecaster of the five specifications compared for the two single-stock series, while the exponential GARCH(1,1) model forecasts more accurately for the S&P 500, whose crash-dominated, high-kurtosis return profile differs markedly from the two individual equities. Taken together, these results show that the theoretical conservatism established for the geometric conditional scale translates into a genuine, if market-dependent, forecasting advantage in practice.</p>Nkatet Siololo, Cornelious Nyakundi, Troon Benedict John
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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https://www.journalajpas.com/index.php/AJPAS/article/view/953Sat, 12 Sep 2026 00:00:00 +0000Mathematical and Statistical Determination of Seismicity Index, Recurrence Interval and Seismic Risk of Shallow Earthquake Occurrence in Anatolian Fault in Turkey
https://www.journalajpas.com/index.php/AJPAS/article/view/954
<p>This study investigates the seismicity index, recurrence interval, and seismic risk of shallow earthquakes along the Anatolian Fault in Turkey using the least squares regression technique. Earthquake data were obtained from the International Seismological Centre (ISC) catalogue, considering events with Mb ≥ 4.0 and focal depths of 0–40 km. A total of 1,008 earthquake events were analysed. The least squares method produced seismicity parameters of a = 6.787 and b = 0.98666, representing the level of seismic activity and the relative occurrence of small versus large earthquakes. These parameters were used to estimate annual occurrence rates, recurrence intervals, and occurrence probabilities for different earthquake magnitudes. Results indicate that seismicity along the Anatolian Fault is dominated by low- to moderate-magnitude earthquakes, while larger events occur less frequently. The seismicity index decreases with increasing magnitude, whereas recurrence intervals become longer, demonstrating an inverse relationship between earthquake size and frequency. Seismic risk increases with longer exposure periods but decreases for higher-magnitude events because of their lower recurrence rates. These findings enhance understanding of the seismic behaviour of the Anatolian Fault and provide valuable information for seismic hazard assessment, earthquake preparedness, resilient infrastructure design, and strategies to reduce the impacts of future earthquakes.</p>J. U. Atsu, A. A. Abong
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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https://www.journalajpas.com/index.php/AJPAS/article/view/954Sat, 12 Sep 2026 00:00:00 +0000Gerber–Shiu Penalty Function for a Dependent Risk Model with Stochastic Premium Income
https://www.journalajpas.com/index.php/AJPAS/article/view/955
<p>This study considers a dependent insurance risk model in which premium income is represented by a stochastic compound Poisson process and the claim mechanism incorporates dependence between claim amounts and subsequent inter-claim times through a stochastic threshold structure. The Gerber–Shiu expected discounted penalty function is investigated for two states determined by the relationship between the original loss amount and the corresponding stochastic threshold. Under the assumption that individual premium amounts follow an exponential distribution, integral equations for the state-dependent Gerber–Shiu functions are established and transformed using Laplace-transform techniques. The resulting expressions are analysed through a characteristic equation, from which the required transform quantities are determined. A defective renewal-equation representation of the Gerber–Shiu functions is subsequently derived using the transformed expressions and appropriate operator identities. Two numerical examples are considered to illustrate the analytical results. In the first example, both the premium and original loss amounts follow exponential distributions. In the second example, a mixture of exponential distributions is introduced for one component of the loss-threshold structure while the premium amount remains exponentially distributed. The resulting ruin probabilities decrease as the initial surplus increases, while differences between the two dependence states are also observed. The analysis provides a mathematical framework for examining ruin-related quantities in a dependent risk model where premium income is stochastic rather than deterministic.</p>Chunyu Xue
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
https://www.journalajpas.com/index.php/AJPAS/article/view/955Mon, 14 Sep 2026 00:00:00 +0000Feature Selection-Assisted Support Vector Machine Classification of Breast Cancer Mammographic Outcomes
https://www.journalajpas.com/index.php/AJPAS/article/view/956
<p><strong>Aims:</strong> This study assessed the effect of feature selection on Support Vector Machine classification of breast cancer mammographic outcomes using image-derived mammographic predictors.</p> <p><strong>Study Design:</strong> The study adopted a secondary-data comparative statistical learning design.</p> <p><strong>Place and Duration of Study:</strong> The study used the publicly available Curated Breast Imaging Subset of the Digital Database for Screening Mammography. The analysis was conducted at the Department of Mathematics, Multimedia University of Kenya.</p> <p><strong>Methodology:</strong> After image matching and preprocessing, 2,863 training observations and 704 testing observations were retained. Thirty-four image-derived predictors were extracted from cropped mammogram images and region of interest masks. The predictors comprised texture, shape and intensity features. Correlation-Based Feature Selection and Elastic Net-regularised multinomial logistic regression were applied before radial basis function Support Vector Machine classification. Model performance was assessed using accuracy, precision, recall, macro F1-score, weighted F1-score and McNemar’s test.</p> <p><strong>Results:</strong> Correlation-Based Feature Selection retained five predictors, reducing the feature space by 85.3%. Elastic Net retained sixteen predictors after coefficient ranking and cross-validated subset selection, reducing the feature space by 52.9%. Elastic Net-SVM achieved the highest accuracy of 0.5369, while the baseline SVM trained on all extracted predictors achieved the highest macro F1-score of 0.5200. McNemar’s tests showed no statistically significant differences in paired classification error rates among the three SVM models at the 5% level.</p> <p><strong>Conclusion:</strong> Feature selection reduced the input feature space and improved model interpretability but did not produce a statistically significant improvement in overall SVM classification performance. The findings highlight the need to report class-level performance, particularly malignant recall, when evaluating feature selection-assisted mammographic classification models.</p>Beryl Kanali, Pius Kihara, Anthony Karanjah
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
https://www.journalajpas.com/index.php/AJPAS/article/view/956Mon, 14 Sep 2026 00:00:00 +0000Integrating Factor Analysis with the Cox Proportional Hazards Model for Neonatal Mortality Analysis Using KDHS 2022 Data
https://www.journalajpas.com/index.php/AJPAS/article/view/957
<p><strong>Aims/Objectives:</strong> To integrate Exploratory Factor Analysis (EFA) with Cox proportional hazards regression to reduce multicollinearity among correlated covariates and identify neonatal mortality risk factors in Kenya.</p> <p><strong>Study Design:</strong> Secondary analysis of a nationally representative cross-sectional demographic health survey, using a retrospective cohort (survival analysis) design.</p> <p><strong>Place and Duration of Study:</strong> The Catholic University of Eastern Africa, using data from the 2022 Kenya Demographic and Health Survey (KDHS); analysis conducted between April 2026 and August 2026.</p> <p><strong>Methodology:</strong> Data from 77,089 live births recorded in the 2022 KDHS were analyzed. Latent dimensions from correlated variables relating to socioeconomic status and fertility history were extracted. Resulting factor scores, together with selected observed covariates, were incorporated into a stratified Cox proportional hazards model. Five alternative model specifications were compared using Akaike and Bayesian Information Criteria, pseudo-<em>R</em>2, concordance index (C- index), events per variable, and generalized variance inflation factors.</p> <p><strong>Results:</strong> Child sex, birth order, preceding birth interval, maternal age at childbirth, pregnancy losses, multiple births, socioeconomic status, and fertility context were significant predictors of neonatal mortality. Female neonates had 30.5% lower hazard of death than males (HR = 0.695; 95% CI: 0.610–0.793), while multiple births had nearly six times the hazard of singletons (HR = 5.795; 95% CI: 4.849–6.925). The EFA-Cox framework required only 13 parameters versus 48 in the conventional model, while improving explained variation (28.7% vs. 14.3%) and discrimination (C-index: 0.787 vs. 0.712) and reducing multicollinearity. Embedding prior child mortality within a latent fertility-context factor, rather than including it directly, retained prognostic value while reducing predictive bias.</p> <p><strong>Conclusion:</strong> The EFA-Cox framework offers a concise, stable, and interpretable approach for modeling neonatal mortality and identifying its determinants in complex demographic survey data.</p>Berit Heddy Atieno, Hellen Waititu, Leah Chege
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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https://www.journalajpas.com/index.php/AJPAS/article/view/957Thu, 24 Sep 2026 00:00:00 +0000Probabilistic Forecasting of Mortality in Kenya Using a Zero-truncated Conway-Maxwell-Poisson Bayesian Generalized Additive Model
https://www.journalajpas.com/index.php/AJPAS/article/view/958
<p><strong>Aims:</strong> To develop the Zero-Truncated Conway-Maxwell-Poisson Bayesian Generalized Additive Model (ZTCMP-BGAM) for probabilistic mortality forecasting in Kenya, estimate its parameters, evaluate its performance against three models, and generate probabilistic forecasts of mortality and life expectancy for 2024 to 2053.</p> <p><strong>Study Design:</strong> Quantitative secondary data analysis and mathematical modeling.</p> <p><strong>Place and Duration of Study:</strong> Kenya, 1950 to 2023 (observation); 2024 to 2053 (forecast horizon).</p> <p><strong>Methodology:</strong> UN WPP 2024 graduated death counts and population exposures for Kenya across 101 ages (1950-2023) were used. The ZTCMP-BGAM embeds a zero-truncated Conway-Maxwell-Poisson distribution with an age-specific dispersion parameter within a Bayesian generalized additive model. Parameters were estimated via penalized log-likelihood with a Laplace approximation, implemented in Template Model Builder. The ZTCMP-BGAM was compared against three models in a two-by-two factorial design crossing zero-truncation and flexible dispersion. Performance was evaluated using BIC, in-sample accuracy, an independent dispersion diagnostic, and backtesting over two holdout periods. Forecasts were generated by extrapolating the additive predictor.</p> <p><strong>Results:</strong> The ZTCMP-BGAM achieved the lowest BIC (66,003.42). Flexible dispersion accounted for 99,290 log-likelihood units of improvement; zero-truncation contributed 1.5 and 0.36 units within the equidispersion and flexible-dispersion classes, respectively. Departures from equidispersion were confirmed at 96 of 101 ages. Primary backtesting (2014-2023) yielded errors of 19.5% and 29.2% for equidispersion and flexible-dispersion models, respectively; sensitivity backtesting (1994-2023) reversed the ranking (31.8% vs. 24.5%). Life expectancy was projected to rise from 65.94 (95% CI: 65.75-66.15) to 81.23 years (95% CI: 78.87-83.59) by 2053.</p> <p><strong>Conclusion:</strong> Flexible age-specific dispersion improves distributional fit; equidispersion is inappropriate across most ages. Out-of-sample forecast performance depends on the mortality dynamics in the holdout period. The framework is transferable to any country relying on UN WPP estimates.</p>Grace Mukami Mwangi, Anthony N. Karanjah, Pius Nderitu Kihara
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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https://www.journalajpas.com/index.php/AJPAS/article/view/958Wed, 30 Sep 2026 00:00:00 +0000Modelling Volatility Dynamics of Monthly Changes in Nigeria’s Savings Deposit Rate: A GARCH Approach
https://www.journalajpas.com/index.php/AJPAS/article/view/959
<p>This study modelled the volatility dynamics of monthly changes in Nigeria's Savings Deposit Rate using the Generalized Autoregressive Conditional Heteroskedasticity (GARCH) framework. Monthly Savings Deposit Rate data covering January 2013 to April 2026 were obtained from the Central Bank of Nigeria Statistical Bulletin and analysed using EViews 10. Descriptive statistics, the Augmented Dickey-Fuller (ADF) test and the ARCH-LM test were employed as preliminary procedures, while ARCH and GARCH models were estimated using Maximum Likelihood. The ADF test showed that the Savings Deposit Rate was non-stationary at level but became stationary after first differencing. The ARCH-LM test provided significant evidence of conditional heteroskedasticity, with an F-statistic of 21.47946 and a probability value of 0.0000, thereby justifying the use of conditional volatility models. The estimated model produced a positive and statistically significant ARCH coefficient of 0.241450 (p = 0.0210), indicating that recent shocks significantly affect current volatility. The GARCH coefficient was positive at 0.284001 but was statistically insignificant at the 5% level (p = 0.0943). The estimated volatility persistence measure, α+β=0.525451, was below unity, indicating a stationary conditional variance process. The estimated half-life of a volatility shock was approximately 1.08 months, suggesting relatively rapid dissipation of volatility shocks. Post-estimation diagnostics showed no significant remaining ARCH effects or residual serial correlation, while the standardised residuals did not significantly depart from normality. The study concludes that monthly changes in Nigeria's Savings Deposit Rate exhibit time-varying conditional volatility and that the model provides an adequate and parsimonious representation of its conditional variance dynamics.</p>Ogike Theresa U., Mbachu Hope I., Anusionwu Collins O., Oguzie Akudo O.
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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https://www.journalajpas.com/index.php/AJPAS/article/view/959Wed, 30 Sep 2026 00:00:00 +0000Comparative Performance of Expectation-Maximization (EM) Algorithm Variants for Finite Mixtures of Linear Regression Models
https://www.journalajpas.com/index.php/AJPAS/article/view/960
<p><strong>Aims/ Objectives:</strong> Finite mixture models, particularly mixtures of linear regressions, are widely used for modeling heterogeneous data. Although the Expectation-Maximization (EM) algorithm is the standard estimation method, variants such as Classification EM (CEM) and Stochastic EM (SEM) offer distinct advantages. However, choosing the optimal algorithm under varying data conditions remains a practical challenge. This research addresses this gap through a systematic empirical comparison of EM, CEM, and SEM using controlled simulations that vary sample size, model complexity, mixing proportions, regression configuration, and cross-validation folds. Prediction accuracy was evaluated using the Mean Root Squared Error of Prediction (MRSEP). Our results demonstrate that sample size, model complexity, mixing proportion, and algorithm choice all significantly influence model performance, and that no single algorithm dominates across all settings. For two-component models, EM and CEM perform similarly and clearly outperform SEM, while the concurrent configuration yields substantially lower prediction errors than the parallel configuration. For three-component models, SEM is best at balanced proportions, whereas at extreme proportions EM is best at upper extremes and SEM at lower extremes for small samples. For four-component models, EM is generally most accurate at lower proportions, with CEM matching at higher proportions and SEM showing slightly higher error. Larger sample sizes generally improve accuracy, though gains vary by algorithm and model complexity. Model estimation is substantially easier at extreme mixing proportions compared to balanced proportions. The choice of cross-validation fold number has no significant impact on accuracy, confirming robustness to the evaluation procedure. Practically, these findings recommend tailoring algorithm selection to the number of components, the mixing proportion, and the sample size, rather than relying on a single universally superior method, thereby offering the scientific community an evidence-based foundation for more reliable and reproducible mixture regression modeling.</p>Hafsa Mohammed, Abdelbaset Abdalla, Omar A. El-Sharif, Abir Hassan Elgihawi, Ahmed Mami
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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https://www.journalajpas.com/index.php/AJPAS/article/view/960Mon, 05 Oct 2026 00:00:00 +0000Application of Logistic Regression in Modelling Depression among Students at Murang’a University of Technology
https://www.journalajpas.com/index.php/AJPAS/article/view/961
<p>Depression is a common mental health disorder worldwide that can adversely affect an individual's thoughts, emotions, communication, and ability to perform everyday activities. Despite its significant impact, stigma surrounding mental illness may discourage early recognition and treatment, resulting in some cases remaining undiagnosed during the mild or moderate stages. When left unaddressed, severe depression may result in substantial functional impairment, disability or suicidal behaviour. Previous studies have examined the prevalence of depression across different populations, with findings varying considerably depending on the characteristics of the study population and the factors considered. This study applied the logistic regression to model the prevalence of depression among students at Murang'a University of Technology (MUT). The specific objectives were to determine the prevalence of depression among MUT students; Identify the factors associated with depression among MUT students and evaluate the predictive performance of logistic regression in modelling depression among MUT students. A sample of 1448 students drawn from the different schools within the university participated in the study. Data were collected using questionnaires that captured respondents' sociodemographic characteristics and other factors associated with depression. The questionnaires were distributed to participants through social media platforms. Proportionate stratified random sampling was first used to ensure representation of students from all schools in accordance with their population sizes, after which simple random sampling was applied to select individual respondents within each stratum. The collected data was analysed using both descriptive and inferential statistical techniques. Depressive symptoms were assessed using the Patient Health Questionnaire-9 (PHQ-9), with a score of 10 or above used as the threshold for identifying depression. The findings indicated that 25.97% of the students exhibited depressive symptoms, comprising 19.61% with moderate symptoms and 6.35% with severe symptoms. Depressive symptoms were significantly more common among male students , students in their third and fourth years of study. The variables that were significantly related to depression were, gender , social support network , financial situation and past abuse, trauma and neglect . The predictive performance of the logistic regression model was evaluated using confusion matrix-based measures. The model demonstrated strong performance, achieving an accuracy of 0.7624, sensitivity of 0.5625, specificity of 0.8341, positive predictive value of 0.5488 and negative predictive value of 0.8416. The findings highlight the importance of developing interventions that address the specific risk and protective factors associated with depression among university students. Further research should also examine the long-term effectiveness and outcomes of such interventions, thereby contributing to the growing body of knowledge on mental health within higher education settings.</p>Loise Muthoni Wahome, Jane Wangui Runo
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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https://www.journalajpas.com/index.php/AJPAS/article/view/961Tue, 06 Oct 2026 00:00:00 +0000The Gerber-Shiu Function for a Class of Dependent Risk Models Perturbed by Brownian Motion
https://www.journalajpas.com/index.php/AJPAS/article/view/962
<p>This study investigates a class of dependent insurance risk models perturbed by Brownian motion and incorporating a random claim-payment threshold. The insurer’s actual indemnity is defined as the minimum of the claim size and the threshold, allowing the model to represent partial claim compensation. The dependence structure is determined by two claim classes according to whether the claim amount exceeds the threshold, with the corresponding inter-claim times following exponential distributions with class-specific parameters. The analysis focuses on the generalised Gerber–Shiu function and distinguishes ruin caused by a claim from ruin caused by oscillation of the diffusion-perturbed surplus process. For both ruin mechanisms, systems of integro-differential equations are derived and their Laplace-transform representations are obtained. A generalised Lundberg equation is then used to characterise the relevant non-negative roots required for the subsequent analysis. On this basis, defective renewal equations are established for the Gerber–Shiu functions associated with the two initial classes. The resulting formulation extends a Brownian-perturbed dependent risk framework by incorporating a claim-payment threshold and provides a unified analytical representation of ruin-related quantities under partial indemnity. The study therefore develops a theoretical basis for examining the effects of threshold-based claim compensation within a dependent risk model subject to diffusion perturbation.</p>Bohui Wang
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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https://www.journalajpas.com/index.php/AJPAS/article/view/962Wed, 07 Oct 2026 00:00:00 +0000Probabilistic Inventory Model for Deteriorating Items with Variable Production Rate under Trade Credit
https://www.journalajpas.com/index.php/AJPAS/article/view/963
<p>Managing deteriorating items requires a strategic inventory model to minimize stocking duration and associated costs. This study develops a probabilistic economic production quantity (EPQ) model for a deteriorating item inventory system with a variable production rate. The model accounts for production rate variations during uptime and incorporates a trade credit policy extended by manufacturers to retailers, as well as partially backlogged shortages. The deterioration rate is assumed to be constant, while the demand rate follows a uniform distribution. Based on these conditions, the study’s cost functions were formulated for two scenarios: when the customer cannot pay the manufacturer before the expiration of the trade credit period, M (i.e., <strong>Scenario 1: </strong>t<sub>4 </sub>≤ M ≤ T), and when the customer can pay before the expiration (i.e., <strong>Scenario 2: </strong>M ≥ T). It was observed from the result of the numerical example that the cost function for Scenario 2 is equivalent to a model without a trade credit policy. Sensitivity analysis showed that offering a moderately extended trade credit period in a production inventory system with partially backlogged shortages is more cost-effective for optimization.</p>Charles Chibuike Christopher, Abimibola Victoria Oladugba
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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https://www.journalajpas.com/index.php/AJPAS/article/view/963Thu, 08 Oct 2026 00:00:00 +0000Area Biased Exp-Gamma Distribution and Its Application
https://www.journalajpas.com/index.php/AJPAS/article/view/964
<p>This study introduces an Area Biased Exp-Gamma (ABEXPG) distribution obtained by applying area-biased weighting to the Exp-Gamma distribution. The proposed model is developed for non-negative continuous data, and its principal statistical and reliability characteristics are investigated. Closed-form expressions are presented for the probability density and cumulative distribution functions, survival and hazard-related functions, moments, harmonic mean, moment-generating and characteristic functions, entropy measures, order statistics, and Bonferroni and Lorenz curves. The unknown model parameter is estimated using the maximum likelihood method, with numerical computation employed because the resulting likelihood equation does not provide a simple explicit solution. The empirical applicability of the ABEXPG distribution is examined using three datasets representing population growth, analgesic relief times, and rainfall. Its goodness of fit is compared with the Area Biased X-Gamma, Area Biased Kpenadidum, and Area Biased one-parameter Linear Exponential distributions using the Akaike information criterion, Bayesian information criterion, Kolmogorov–Smirnov statistic, and associated p-values. For the three datasets reported, the ABEXPG distribution produced smaller reported Akaike information criterion and Kolmogorov–Smirnov statistic values than the comparison models. These empirical results indicate that the proposed distribution may provide a useful alternative for modelling suitable non-negative continuous datasets.</p>N. R. Bhandale, N. W. Andure (Yawale), R. B. Ade
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
https://creativecommons.org/licenses/by/4.0
https://www.journalajpas.com/index.php/AJPAS/article/view/964Tue, 13 Oct 2026 00:00:00 +0000A Flexible Continuous AP Distribution: Theory, Estimation and Applications
https://www.journalajpas.com/index.php/AJPAS/article/view/965
<p>This study introduces a continuous probability distribution, designated the AP distribution, and examines its theoretical properties and application to observed data. The proposed density is constructed from a positive, integrable kernel and a corresponding normalising constant. Its probability density function and cumulative distribution function are presented, together with the hazard rate function. The model is symmetric about zero, and its density changes with the shape parameter. Analytical derivations address the raw moments, mean, variance, skewness, kurtosis, moment-generating function and characteristic function. In particular, symmetry implies that the odd-order moments vanish. The shape parameter is estimated using maximum likelihood estimation, with numerical optimisation implemented in R because the likelihood equation does not admit an explicit analytical solution. A numerical illustration is provided, followed by an application to 10 observations of glass fibre strength. The proposed model is compared with normal and logistic distributions using log-likelihood, Akaike information criterion, Bayesian information criterion and the one-sample Kolmogorov–Smirnov test. For the reported dataset, the normal distribution has the lowest Akaike and Bayesian information criterion values, whereas the AP distribution has the smallest Kolmogorov–Smirnov statistic. These findings demonstrate the implementation of the proposed framework and show that its comparative performance depends on the goodness-of-fit measure considered. Further applications are required to assess performance across other datasets.</p>Ashutosh Pandey
Copyright (c) 2026 Author(s). The licensee is the journal publisher. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
https://creativecommons.org/licenses/by/4.0
https://www.journalajpas.com/index.php/AJPAS/article/view/965Sat, 17 Oct 2026 00:00:00 +0000