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1.
Axioms ; 12(4):327, 2023.
Artículo en Inglés | ProQuest Central | ID: covidwho-2304627

RESUMEN

Modeling real-life pandemics is very important;this study focuses on introducing a new superior flexible extension of the asymmetric Haq distribution known as the power Haq distribution (PHD). The most fundamental mathematical properties are derived. We determine its parameters using ten estimation methods. The asymptotic behavior of its estimators is investigated through simulation, and a comparison is done to find out the most efficient method for estimating the parameters of the distribution under consideration. We use a sample for the COVID-19 data set to evaluate the proposed model's performance and usefulness in fitting the data set in comparison to other well-known models.

2.
PLoS One ; 18(2): e0281474, 2023.
Artículo en Inglés | MEDLINE | ID: covidwho-2230287

RESUMEN

In this paper, we introduced a novel general two-parameter statistical distribution which can be presented as a mix of both exponential and gamma distributions. Some statistical properties of the general model were derived mathematically. Many estimation methods studied the estimation of the proposed model parameters. A new statistical model was presented as a particular case of the general two-parameter model, which is used to study the performance of the different estimation methods with the randomly generated data sets. Finally, the COVID-19 data set was used to show the superiority of the particular case for fitting real-world data sets over other compared well-known models.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Modelos Estadísticos , Distribuciones Estadísticas
3.
PLoS One ; 18(1): e0278659, 2023.
Artículo en Inglés | MEDLINE | ID: covidwho-2197052

RESUMEN

During the course of this research, we came up with a brand new distribution that is superior; we then presented and analysed the mathematical properties of this distribution; finally, we assessed its fuzzy reliability function. Because the novel distribution provides a number of advantages, like the reality that its cumulative distribution function and probability density function both have a closed form, it is very useful in a wide range of disciplines that are related to data science. One of these fields is machine learning, which is a sub field of data science. We used both traditional methods and Bayesian methodologies in order to generate a large number of different estimates. A test setup might have been carried out to assess the effectiveness of both the classical and the Bayesian estimators. At last, three different sets of Covid-19 death analysis were done so that the effectiveness of the new model could be demonstrated.


Asunto(s)
COVID-19 , Humanos , Teorema de Bayes , Reproducibilidad de los Resultados , COVID-19/epidemiología , Funciones de Verosimilitud
4.
Math Biosci Eng ; 20(2): 3324-3341, 2023 01.
Artículo en Inglés | MEDLINE | ID: covidwho-2201223

RESUMEN

The initial COVID-19 vaccinations were created and distributed to the general population in 2020 thanks to emergency authorization and conditional approval. Consequently, numerous countries followed the process that is currently a global campaign. Taking into account the fact that people are being vaccinated, there are concerns about the effectiveness of that medical solution. Actually, this study is the first one focusing on how the number of vaccinated people might influence the spread of the pandemic in the world. From the Global Change Data Lab "Our World in Data", we were able to get data sets about the number of new cases and vaccinated people. This study is a longitudinal one from 14/12/2020 to 21/03/2021. In addition, we computed Generalized log-Linear Model on count time series (Negative Binomial distribution due to over dispersion in data) and implemented validation tests to confirm the robustness of our results. The findings revealed that when the number of vaccinated people increases by one new vaccination on a given day, the number of new cases decreases significantly two days after by one. The influence is not notable on the same day of vaccination. Authorities should increase the vaccination campaign to control well the pandemic. That solution has effectively started to reduce the spread of COVID-19 in the world.


Asunto(s)
COVID-19 , Humanos , Vacunas contra la COVID-19 , Programas de Inmunización , Modelos Lineales , Vacunación
5.
Math Biosci Eng ; 20(2): 2847-2873, 2023 01.
Artículo en Inglés | MEDLINE | ID: covidwho-2201221

RESUMEN

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.


Asunto(s)
COVID-19 , Humanos , Modelos Estadísticos , Simulación por Computador , Redes Neurales de la Computación , Predicción
6.
PLoS One ; 17(10): e0276688, 2022.
Artículo en Inglés | MEDLINE | ID: covidwho-2098752

RESUMEN

The objective of this study is to construct a new distribution known as the weighted Burr-Hatke distribution (WBHD). The PDF and CDF of the WBHD are derived in a closed form. Moments, incomplete moments, and the quantile function of the proposed distribution are derived mathematically. Eleven estimate techniques for estimating the distribution parameters are discussed, and numerical simulations are utilised to evaluate the various approaches using partial and overall rankings. According to the findings of this study, it is recommended that the maximum product of spacing (MPSE) estimator of the WBHD is the best estimator according to overall rank table. The actuarial measurements were derived to the suggested distribution. By contrasting the WBHD with other competitive distributions using two different actual data sets collected from the COVID-19 mortality rates, we show the importance and flexibility of the WBHD.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Arabia Saudita/epidemiología , Modelos Estadísticos
7.
Complexity ; 2022, 2022.
Artículo en Inglés | ProQuest Central | ID: covidwho-2079089

RESUMEN

The extended reduced Kies distribution (ExRKD), which is an asymmetric flexible extension of the reduced Kies distribution, is the subject of this research. Some of its most basic mathematical properties are deduced from its formal definitions. We computed the ExRKD parameters using eight well-known methods. A full simulation analysis was done that allows the study of these estimators’ asymptotic behavior. The efficiency and applicability of the ExRKD are investigated via the modeling of COVID-19 and milk data sets, which demonstrates that the ExRKD delivers a better match to the data sets when compared to competing models.

8.
Journal of Function Spaces ; : 1-21, 2022.
Artículo en Inglés | Academic Search Complete | ID: covidwho-1891971

RESUMEN

The power XLindley (PXL) distribution is introduced in this study. It is a two-parameter distribution that extends the XLindley distribution established in this paper. Numerous statistical characteristics of the suggested model were determined analytically. The proposed model's fuzzy dependability was statistically assessed. Numerous estimation techniques have been devised for the purpose of estimating the proposed model parameters. The behaviour of these factors was examined using randomly generated data and developed estimation approaches. The suggested model seems to be superior to its base model and other well-known and related models when applied to the COVID-19 data set. [ FROM AUTHOR] Copyright of Journal of Function Spaces is the property of Hindawi Limited and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

9.
Alexandria Engineering Journal ; 2022.
Artículo en Inglés | ScienceDirect | ID: covidwho-1800226

RESUMEN

We present a new continuous lifetime model with four parameters by combining the Lomax and the Weibull distributions. The extended odd Weibull Lomax (EOWL) distribution is what we’ll call it. This new distribution possesses several desirable properties thanks to the simple linear representation of its hazard rate function, moments, and moment -generating function, with stress-strength reliability that are provided in a simple closed forms. The parameters of the EOWL model are estimated using classical methods such as the maximum likelihood (MLE) and the maximum product of spacing (MPS) and estimated also but using a non-classical method such as Bayesian analytical approaches. Bayesian estimation is performed using the Monte Carlo Markov Chain method. Monte Carlo simulation are used to assess the effectiveness of the estimation methods throughout the Metropolis Hasting (MH) algorithm. To illustrate the suggested distribution’s effectiveness and suitability for simulating real-world pandemics, we used three existing COVID-19 data sets from the United Kingdom, the United States of America, and Italy which are studied to serve as illustrative examples. We graphed the P-P plots and TTT plots for the proposed distribution proving its superiority in a graphical manner for modelling the three data sets in the paper.

10.
Complexity ; 2021, 2021.
Artículo en Inglés | ProQuest Central | ID: covidwho-1606804

RESUMEN

This paper aims to introduce a superior discrete statistical model for the coronavirus disease 2019 (COVID-19) mortality numbers in Saudi Arabia and Latvia. We introduced an optimal and superior statistical model to provide optimal modeling for the death numbers due to the COVID-19 infections. This new statistical model possesses three parameters. This model is formulated by combining both the exponential distribution and extended odd Weibull family to formulate the discrete extended odd Weibull exponential (DEOWE) distribution. We introduced some of statistical properties for the new distribution, such as linear representation and quantile function. The maximum likelihood estimation (MLE) method is applied to estimate the unknown parameters of the DEOWE distribution. Also, we have used three datasets as an application on the COVID-19 mortality data in Saudi Arabia and Latvia. These three real data examples were used for introducing the importance of our distribution for fitting and modeling this kind of discrete data. Also, we provide a graphical plot for the data to ensure our results.

11.
PLoS One ; 16(7): e0254999, 2021.
Artículo en Inglés | MEDLINE | ID: covidwho-1325438

RESUMEN

Over the past few months, the spread of the current COVID-19 epidemic has caused tremendous damage worldwide, and unstable many countries economically. Detailed scientific analysis of this event is currently underway to come. However, it is very important to have the right facts and figures to take all possible actions that are needed to avoid COVID-19. In the practice and application of big data sciences, it is always of interest to provide the best description of the data under consideration. The recent studies have shown the potential of statistical distributions in modeling data in applied sciences, especially in medical science. In this article, we continue to carry this area of research, and introduce a new statistical model called the arcsine modified Weibull distribution. The proposed model is introduced using the modified Weibull distribution with the arcsine-X approach which is based on the trigonometric strategy. The maximum likelihood estimators of the parameters of the new model are obtained and the performance these estimators are assessed by conducting a Monte Carlo simulation study. Finally, the effectiveness and utility of the arcsine modified Weibull distribution are demonstrated by modeling COVID-19 patients data. The data set represents the survival times of fifty-three patients taken from a hospital in China. The practical application shows that the proposed model out-classed the competitive models and can be chosen as a good candidate distribution for modeling COVID-19, and other related data sets.


Asunto(s)
COVID-19/epidemiología , COVID-19/mortalidad , Modelos Estadísticos , Pandemias , SARS-CoV-2/patogenicidad , COVID-19/diagnóstico , COVID-19/fisiopatología , China/epidemiología , Tos/diagnóstico , Tos/fisiopatología , Fatiga/diagnóstico , Fatiga/fisiopatología , Fiebre/diagnóstico , Fiebre/fisiopatología , Hospitales , Humanos , Método de Montecarlo , Análisis de Supervivencia
12.
Journal of King Saud University - Science ; 2020.
Artículo en Inglés | ScienceDirect | ID: covidwho-917346

RESUMEN

Discrete distributions have their important in modeling count data in several applied fields such as epidemiology, public health, sociology, medicine, and agriculture. This paper discusses the estimation of the parameters of two discrete models called discrete Poisson-Lindley and discrete Lindley distributions, using several frequentist estimation methods. Parameter estimation can provide a guideline for choosing the best method of estimation for the model parameters, which would be very important to reliability engineers and applied statisticians. The finite sample properties of the estimates are explored using extensive simulation results. The ordering performance of the proposed estimators is determined by the partial and overall ranks of different parametric values. We also derived two important actuarial measures of the two discrete models. A computational study for the two risk measures is conducted. Finally, applications of the two discrete distributions have been examined and compared with other discrete distributions via three data sets from the medicine field including two COVID-19 data sets.

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