A Novel Regression Model for Fractiles: Formulation, Computational Aspects, and Applications to Medical Data

Fractal and Fractional, Journal Year: 2023, Volume and Issue: 7(2), P. 169 - 169

Published: Feb. 7, 2023

Covariate-related response variables that are measured on the unit interval frequently arise in diverse studies when index and proportion data of interest. A regression mean is commonly used to model this relationship. Instead relying mean, which sensitive atypical less general, we can estimate such a relation using fractile regression. point probability density curve area under between origin equal specified fraction. Fractile or quantile modeling has been considered for some statistical distributions. Our objective present article formulate novel based parametric distribution. developed reparameterizing initial Then, introduce functional form through link function. The main features new distribution, as well density, functions, obtained. We consider brand-new distribution fractiles continuous dependent variable (response) bounded (0, 1). discuss an R package with random number generators functions cumulative quantile, addition estimation checking. original distribution-free regression, lately employed several investigations. use fit apply it two case COVID-19 medical from Brazil United States illustration.

Language: Английский

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Quasi-Cauchy Regression Modeling for Fractiles Based on Data Supported in the Unit Interval

Fractal and Fractional, Journal Year: 2023, Volume and Issue: 7(9), P. 667 - 667

Published: Sept. 4, 2023

A fractile is a location on probability density function with the associated surface being proportion of such function. The present study introduces novel methodological approach to modeling data within continuous unit interval using or quantile regression. This has unique advantage as it allows for direct interpretation response variable in relation explanatory variables. new provides robustness against outliers and permits heteroscedasticity be modeled, making tool analyzing datasets diverse characteristics. Importantly, our does not require assumptions about distribution variable, offering increased flexibility applicability across variety scenarios. Furthermore, addresses mitigates criticisms limitations inherent existing methodologies, thereby giving an improved framework interval. We validate effectiveness introduced two empirical applications, which highlight its practical utility superior performance real-world settings.

Language: Английский

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A new quantile regression model with application to human development index

Computational Statistics, Journal Year: 2023, Volume and Issue: 39(6), P. 2925 - 2948

Published: Sept. 22, 2023

Language: Английский

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Blockchain in clinical trials: Bibliometric and network studies of applications, challenges, and future prospects based on data analytics

Computer Methods and Programs in Biomedicine, Journal Year: 2024, Volume and Issue: 255, P. 108321 - 108321

Published: July 14, 2024

Language: Английский

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Associations between PM2.5 and its chemical constituents and blood pressure: a cross-sectional study

Journal of Hypertension, Journal Year: 2024, Volume and Issue: unknown

Published: July 4, 2024

Objectives: To investigate the associations between PM 2.5 and its chemical constituents with blood pressure (BP), assess effects across BP quantiles, identify key constituent elevating BP. Methods: A total of 36 792 adults were included in cross-sectional study, representing 25 districts/counties southeast China. Quantile regression models applied to estimate (ammonium [NH 4 + ], nitrate [NO 3 − sulfate [SO 2− black carbon [BC], organic matter [OM]) systolic (SBP), diastolic (DBP), mean artery (MAP). weighted quantile sum (WQS) index was used relative importance each joint effect on Results: The adverse interquartile range (IQR) increase , NH NO SO BC found be greater elevated BP, especially when SBP exceeded 133 mmHg DBP 82 mmHg. Each IQR all five associated ( β [95% CI]: 0.90 [0.75, 1.05]), : 0.44 [0.34, 0.53]), MAP 0.57 [0.45, 0.69]), (for SBP: weight = 99.43%; for DBP: 12.78%; MAP: 60.73%) 87.06%; 39.07%) predominantly influencing these effects. risks exhibited an upward trend from 70 th (SBP mmHg, mmHg). Conclusion: Long-term exposure increased risk being main contributors, such significantly stronger at 70th 90th quantiles

Language: Английский

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Burden of chronic obstructive pulmonary disease attributable to non-optimal temperature, 1990–2044: six countries on the same isotherm

BMC Public Health, Journal Year: 2024, Volume and Issue: 24(1)

Published: Dec. 18, 2024

With the frequent occurrence of extreme weather worldwide, non-optimal temperature increased risk death from respiratory diseases. The burden on chronic obstructive pulmonary disease (COPD) was quantitatively assessed, and its influencing factors were discussed to provide a basis for prevention treatment COPD. Based GBD 2019, we characterized age-standardized mortality rate (ASMR) years life lost (ASYR) COPD attributable in three groups countries at different isotherms (China USA, South Africa Australia, Iraq Portugal) between 1990 2019. We constructed age-period-cohort model analyze age, period cohort effects Bayesian predict ASMR six countries. analyzed relationship socio-demographic index (SDI) with ASYR by restricted cubic spline quantile regression using data 21 regions. 2019 11.03/100,000 (China), 5.62/100,000 (USA), 2/100,000 (Australia), 0.93/100,000 (Iraq), 3.74/100,000 (Portugal), 4.13/100,000 (South Africa). Low had greater impact showed an increasing trend effect only decreasing China, trend. higher concentrated areas SDI values 0.39–0.78. Implied fit meaningful P5 P75, P5, P25, P95. predicted upward over next 25 USA. In caused temperature, low played more important role, it affected sex, period, SDI. Over years, decline all except

Language: Английский

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Flexible CDF-quantile distributions on the closed unit interval, with software and applications

Communication in Statistics- Theory and Methods, Journal Year: 2023, Volume and Issue: 53(11), P. 3876 - 3898

Published: Jan. 17, 2023

Formulae display:?Mathematical formulae have been encoded as MathML and are displayed in this HTML version using MathJax order to improve their display. Uncheck the box turn off. This feature requires Javascript. Click on a formula zoom.

Language: Английский

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Extreme Path Delay Estimation of Critical Paths in Within-Die Process Fluctuations Using Multi-Parameter Distributions

Journal of Low Power Electronics and Applications, Journal Year: 2023, Volume and Issue: 13(1), P. 22 - 22

Published: March 20, 2023

Two multi-parameter distributions, namely the Pearson type IV and metalog are discussed suggested as alternatives to normal distribution for modelling path delay data that determines maximum clock frequency (FMAX) of a microprocessor or other digital circuit. These distributions outperform in goodness-of-fit statistics simulated derived from fabricated microcontroller, with six-term offering best fit. Furthermore, 99.7% confidence intervals calculated some extreme quantiles on each dataset using previous distributions. Considering estimates golden standard, relative errors single paths vary between 4 14% distribution. Finally, within-die (WID) variation critical multiple is under assumption independence paths. Its density function then used compute different delays varying numbers paths, assuming has one standard. For 100 at most With 1000 10,000 corresponding extend up 16 19%, respectively.

Language: Английский

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Inference Based on the Stochastic Expectation Maximization Algorithm in a Kumaraswamy Model with an Application to COVID-19 Cases in Chile

Mathematics, Journal Year: 2023, Volume and Issue: 11(13), P. 2894 - 2894

Published: June 28, 2023

Extensive research has been conducted on models that utilize the Kumaraswamy distribution to describe continuous variables with bounded support. In this study, we examine trapezoidal model. Our objective is propose a parameter estimation method for model using stochastic expectation maximization algorithm, which effectively tackles challenges commonly encountered in traditional algorithm. We then apply our results modeling of daily COVID-19 cases Chile.

Language: Английский

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Quantile-Based Multivariate Log-Normal Distribution

Symmetry, Journal Year: 2023, Volume and Issue: 15(8), P. 1513 - 1513

Published: July 31, 2023

We introduce a quantile-based multivariate log-normal distribution, providing new skewed distribution with positive support. The parameters of this are interpretable in terms quantiles marginal distributions and associations between pairs variables, desirable feature for statistical modeling purposes. derive properties the involving transformations, closed-form expressions mixed moments, expected value, covariance matrix, mode, Shannon entropy, Kullback–Leibler divergence. also present results on marginalization, conditioning, independence. Additionally, we discuss parameter estimation verify its performance through simulation studies. evaluate model fitting based Mahalanobis-type distances. An application to children data is presented.

Language: Английский

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