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1.
Heliyon ; 10(9): e29861, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38707268

RESUMO

Probability distributions play a pivotal and significant role in modeling real-life data in every field. For this activity, a series of probability distributions have been introduced and exercised in applied sectors. This paper also contributes a new method for modeling continuous data sets. The proposed family is called the exponent power sine-G family of distributions. Based on the exponent power sine-G method, a new model, namely, the exponent power sine-Weibull model is studied. Several mathematical properties such as quantile function, identifiability property, and rth moment are derived. For the exponent power sine-G method, the maximum likelihood estimators are obtained. Simulation studies are also presented. Finally, the optimality of the exponent power sine-Weibull model is shown by taking two applications from the healthcare sector. Based on seven evaluating criteria, it is demonstrated that the proposed model is the best competing distribution for analyzing healthcare phenomena.

2.
Environ Sci Pollut Res Int ; 31(23): 33495-33514, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38684613

RESUMO

The research aims to propose a feature selection model for hydraulic analysis as such a model has not been proposed previously. For this purpose, hybrids of three metaheuristic algorithms, particle swarm optimization (PSO), ant colony optimization (ACO), and genetic algorithm (GA) with two machine learning models which are support vector machine (SVM) and K-nearest neighbor (KNN) are employed. The dataset considered was hydraulic having an association with flood and possessed topographic, geo-environmental, and human-induced variables. The dataset considered had multicollinearity heteroscedasticity and autocorrelation problems. The metaheuristic algorithms were evaluated by varying the number of population size. Among them, PSO performed better by providing an appropriate number of features with a lower number of iterations. We have analyzed the performance of SVM with different kernels; linear, radial basis function (RBF), sigmoid, and polynomial, as the original SVM is designed only for linear datasets but the hydraulic dataset possesses non-linear characteristics as well. The performance of different kernels in terms of their accuracies is evaluated and recorded. This study showed that RBF performed the best and sigmoid showed the least accuracy for GA, PSO, and ACO algorithms. The performance of KNN is evaluated in terms of accuracies by varying the K-values. It was found that KNN shows low accuracy with a small K-value which then attained a maximum level by increasing K-values, and it finally started decreasing, explicitly, by further enhancing K-values. While comparing the performance of hybrids of GA, PSO, and ACO with SVM and KNN, it was analyzed that KNN performed better with these meta-heuristics with PSO-KNN which performed the best among the baseline models. Thus, the study proposes that PSO-KNN can be utilized as a feature selection technique to obtain optimal data subsets for hydraulic modeling and analysis.


Assuntos
Algoritmos , Inundações , Aprendizado de Máquina , Máquina de Vetores de Suporte , Análise Espacial , Modelos Teóricos
3.
PLoS One ; 18(11): e0285992, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37963157

RESUMO

Gul and Mohsin 2021 developed a new modified form of renowned "Half logistic" distribution introduced by Balakrishnan (1991) and named it half logistic-truncated exponential distribution (HL-TEXPD). Some mathematical characteristics are studied, including hazard function, Pth percentile, moment generating function and Shannon entropy. Simulation study is performed to examine the behaviour of parameter estimates. The proposed model is fitted on three real data sets to check its efficacy. Additionally, TTT (total time on test) plot is drawn to study the failure rate of the three data sets. The results verdict that HL-TEXPD can be efficiently utilized in the field of engineering and medical sciences based on the data sets under study contrary to the classical and baseline models.


Assuntos
Simulação por Computador , Distribuições Estatísticas , Entropia
4.
Heliyon ; 9(6): e17238, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37426796

RESUMO

Statistical modeling is a crucial phase for decision-making and predicting future events. Data arising from engineering-related fields have most often complex structures whose failure rate possesses mixed state behaviors (i.e., non-monotonic shapes). For the data sets whose failure rates are in the mixed state, the utilization of the traditional probability models is not a suitable choice. Therefore, searching for more flexible probability models that are capable of adequately describing the mixed state failure data sets is an interesting research topic for researchers. In this paper, we propose and study a new statistical model to achieve the above goal. The proposed model is called a new beta power very flexible Weibull distribution and is capable of capturing five different patterns of the failure rate such as uni-modal, decreasing-increasing-decreasing, bathtub, decreasing, increasing-decreasing-increasing shapes. The estimators of the new beta power very flexible Weibull distribution are obtained using the maximum likelihood method. The evaluation of the estimators is assessed by conducting a simulation study. Finally, the usefulness and applicability of the new beta power very flexible Weibull distribution are shown by analyzing two engineering data sets. Using four information criteria, it is observed that the new beta power very flexible Weibull distribution is the best-suited model for dealing with failure times data sets.

5.
Diagnostics (Basel) ; 13(7)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37046528

RESUMO

The rising number of confirmed cases and deaths in Pakistan caused by the coronavirus have caused problems in all areas of the country, not just healthcare. For accurate policy making, it is very important to have accurate and efficient predictions of confirmed cases and death counts. In this article, we use a coronavirus dataset that includes the number of deaths, confirmed cases, and recovered cases to test an artificial neural network model and compare it to different univariate time series models. In contrast to the artificial neural network model, we consider five univariate time series models to predict confirmed cases, deaths count, and recovered cases. The considered models are applied to Pakistan's daily records of confirmed cases, deaths, and recovered cases from 10 March 2020 to 3 July 2020. Two statistical measures are considered to assess the performances of the models. In addition, a statistical test, namely, the Diebold and Mariano test, is implemented to check the accuracy of the mean errors. The results (mean error and statistical test) show that the artificial neural network model is better suited to predict death and recovered coronavirus cases. In addition, the moving average model outperforms all other confirmed case models, while the autoregressive moving average is the second-best model.

6.
Math Biosci Eng ; 20(2): 2847-2873, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36899561

RESUMO

Statistical modeling and forecasting of time-to-events data are crucial in every applied sector. For the modeling and forecasting of such data sets, several statistical methods have been introduced and implemented. This paper has two aims, i.e., (i) statistical modeling and (ii) forecasting. For modeling time-to-events data, we introduce a new statistical model by combining the flexible Weibull model with the Z-family approach. The new model is called the Z flexible Weibull extension (Z-FWE) model, where the characterizations of the Z-FWE model are obtained. The maximum likelihood estimators of the Z-FWE distribution are obtained. The evaluation of the estimators of the Z-FWE model is assessed in a simulation study. The Z-FWE distribution is applied to analyze the mortality rate of COVID-19 patients. Finally, for forecasting the COVID-19 data set, we use machine learning (ML) techniques i.e., artificial neural network (ANN) and group method of data handling (GMDH) with the autoregressive integrated moving average model (ARIMA). Based on our findings, it is observed that ML techniques are more robust in terms of forecasting than the ARIMA model.


Assuntos
COVID-19 , Humanos , Modelos Estatísticos , Simulação por Computador , Redes Neurais de Computação , Previsões
7.
Math Biosci Eng ; 20(1): 337-364, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36650769

RESUMO

Statistical methodologies have broader applications in almost every sector of life including education, hydrology, reliability, management, and healthcare sciences. Among these sectors, statistical modeling and predicting data in the healthcare sector is very crucial. In this paper, we introduce a new method, namely, a new extended exponential family to update the distributional flexibility of the existing models. Based on this approach, a new version of the Weibull model, namely, a new extended exponential Weibull model is introduced. The applicability of the new extended exponential Weibull model is shown by considering two data sets taken from the health sciences. The first data set represents the mortality rate of the patients infected by the coronavirus disease 2019 (COVID-19) in Mexico. Whereas, the second set represents the mortality rate of COVID-19 patients in Holland. Utilizing the same data sets, we carry out forecasting using three machine learning (ML) methods including support vector regression (SVR), random forest (RF), and neural network autoregression (NNAR). To assess their forecasting performances, two statistical accuracy measures, namely, root mean square error (RMSE) and mean absolute error (MAE) are considered. Based on our findings, it is observed that the RF algorithm is very effective in predicting the death rate of the COVID-19 data in Mexico. Whereas, for the second data, the SVR performs better as compared to the other methods.


Assuntos
COVID-19 , Humanos , Reprodutibilidade dos Testes , COVID-19/epidemiologia , Modelos Estatísticos , Redes Neurais de Computação , Aprendizado de Máquina
8.
Environ Sci Pollut Res Int ; 29(47): 71190-71207, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35595905

RESUMO

The current study looks at the causes of carbon dioxide (CO2) emissions by considering the implications of remittances in the presence of economic growth, financial development, and energy consumption in the case of selected four G-20 economies over the period 1990-2019. This study first uses the dynamic simulated ARDL model to stimulate, estimate, and plot to predict graphs of negative and positive changes occurring in the variables along with their short-run and long-run relationships. Results of the ARDL bounds test confirm a long-term relationship among remittances, financial development, economic growth energy consumption, and CO2 emissions. Furthermore, the error correction model (ECM) also confirms the long-run relationship among CO2 emissions, remittances, financial development, economic growth, and energy use. The results of a novel dynamic simulated ARDL disclosed that financial development is completely connected to CO2 emissions in Mexico and India in the long run. On the other hand, results confirm that there is a positive relationship between remittances and CO2 emissions in the case of Australia, Germany, and India, but this relationship is insignificant with CO2 emissions in the case of Mexico. The result further disclosed that renewable energy exerts a significant impact on CO2 in Australia, Mexico, India, and Germany in the long run while remittances wield a significant impact on CO2 emissions in Australia, Mexico, and India. Moreover, the findings concluded that GDP has significant nexus with CO2 in the long run in the case of Australia, Mexico, and Germany. This study uses up new visions for the economies of G-20 countries to sustain financial and economic growth by protecting the environment from pollution through its efficient national environmental policy, fiscal policy, and monetary policy.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Dióxido de Carbono/análise , Política Ambiental , Poluição Ambiental , Energia Renovável
9.
Int J Health Plann Manage ; 35(4): 818-831, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31846140

RESUMO

As a result of the recent energy crisis and rapid industrialization in Pakistan, significant attention has turned toward alternative energy resources, CO2 emissions, and health-related issues. The adoption of renewable energies will not only accomplish the energy demand in the economy but will also provide a healthy environment. Therefore, it is essential to understand the linkages between trade, renewable energy, CO2 emissions, and health expenditures with a special focus on an emerging economy like Pakistan. This study used time series data from the 1998-2017 period and adopted the simultaneous equation approach for empirical analysis. The results show that an increase in trade volume positively contributes to the amount of CO2 emissions and, as a result, CO2 increases health expenditures. Conversely, renewable energy has a negative association with health expenditures and CO2 emission, signifying the importance of renewable energy in enhancing environmental quality and reducing health expenditures, which are adversely affected due to CO2 emissions. The empirical findings suggest that the government of Pakistan needs proper policy guidelines for renewable energy adoption in the industrial sector and that such guidelines can be further accommodated and adjusted in other determinants of the economy.


Assuntos
Dióxido de Carbono/efeitos adversos , Dióxido de Carbono/análise , Comércio , Gastos em Saúde/tendências , Energia Renovável , Pesquisa Empírica , Humanos , Cooperação Internacional , Paquistão , Formulação de Políticas
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