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AbstractThis article presents a method for predicting the downtime distribution for a new complex electronic equipment. A theoretical discussion is given which indicates that the downtime distribution for such an equipment can be represented by a lognormal function. Experimental data are shown which establish that the two‐parameter lognormal distribution function adequately describes the downtimes of a diverse group of electronic equipments. It is concluded that this analytical expression for the downtime distribution of complex electronic equipments provides the basis for a quantitative and scientific approach to the measurement and prediction of maintainability. This approach takes account of equipment maintenance characteristics and maintenance personnel capabilities.

A widely accepted criterion for the pro-poorness of an income growth pattern is that it should reduce a (chosen) measure of poverty by \textit{more} than if all incomes were growing equi-proportionately. Inequality reduction is not generally seen as either necessary or sufficient for pro-poorness. As empirical income distributions fit well to the lognormal form, lognormality has sometimes been assumed in order to determine analytically the poverty effects of income growth. We show that in a lognormal world, growth is pro-poor in the above sense, if and only if it is inequality-reducing. It follows that lognormality may not be a good paradigm by means of which to examine pro-poorness issues. In contrast, some popular 3-parameter forms offer the ability to conduct nuanced investigation of the pro-poorness growth-inequality nexus.

In 1987, James and Knuiman published their analysis of a comprehensive domestic water use study conducted in Perth, Western Australia to quantify the components of water usage in approximately 3000 households. This manuscript corrects errors and omissions about James and Knuiman's study in the U.S. EPA's Exposure Factors Handbook, and it shows James and Knuiman's results in a form and notation more readily used in Monte Carlo simulations.

Minimum surgical times are positive and often large. The lognormal distribution has been proposed for modeling surgical data, and the three‐parameter form of the lognormal, which includes a location parameter, should be appropriate for surgical data. We studied the goodness‐of‐fit performance, as measured by the Shapiro‐Wilk p‐value, of three estimators of the location parameter for the lognormal distribution, using a large data set of surgical times. Alternative models considered included the normal distribution and the two‐parameter lognormal model, which sets the location parameter to zero. At least for samples with n > 30, data adequately fit by the normal had significantly smaller skewness than data not well fit by the normal, and data with larger relative minima (smallest order statistic divided by the mean) were better fit by a lognormal model. The rule "If the skewness of the data is greater than 0.35, use the three‐parameter lognormal with the location parameter estimate proposed by Muralidhar & Zanakis (1992), otherwise, use the two‐parameter model" works almost as well at specifying the lognormal model as more complex guidelines formulated by linear discriminant analysis and by tree induction.

[EN] In this paper, estimators of the Nakagami-lognormal (NL) distribution based on the method of log-moments have been derived and thoroughly analyzed. Unlike maximum likelihood (ML) estimators, the log-moment estimators of the NL distribution are obtained using straightforward equations with a unique solution. Also, their performance has been evaluated using the sample mean, confidence regions and normalized mean square error (NMSE). The NL distribution has been extensively used to model composite small-scale fading and shadowing in wireless communication channels. This distribution is of interest in scenarios where the small-scale fading and the shadowing processes cannot be easily separated such as the vehicular environment. ; This work has been funded in part by the Programa de Estancias de Movilidad de Profesores e Investigadores en Centros Extranjeros de Ensenanza Superior e Investigacion of the Ministerio de Educacion, Cultura y Deporte, Spain, PR2015-00151 and by the Ministerio de Economia, Industria y Competitividad of the Spanish Government under the national project TEC2017-86779-C2-2-R, through the Agencia Estatal de Investigacion (AEI) and the Fondo Europeo de Desarrollo Regional (FEDER). ; Reig, J.; Brennan, C.; Rodrigo Peñarrocha, VM.; Rubio Arjona, L. (2019). Log-moment estimators of the Nakagami-lognormal distribution. EURASIP Journal on Wireless Communications and Networking. 1-10. https://doi.org/10.1186/s13638-018-1328-6 ; S ; 1 ; 10 ; J. M. Ho, G. L. Stüber, in Co-channel interference of microcellular systems on shadowed Nakagami fading channels. Proc. IEEE 43rd Vehicular Technology Conference, 1993 (VTC 93) (IEEESecaucus, 1993), pp. 568–571. ; A. A. Abu-Dayya, N. C. Beaulieu, Micro- and macrodiversity NCFSK (DPSK) on shadowed Nakagami-fading channels. IEEE Trans. Commun.42(9), 2693–2702 (1994). ; X. Wang, W. Wang, Z. Bu, Fade statistics for selection diversity in Nakagami-lognormal fading channels. Electron. Lett.42(18), 1046–1047 (2006). ; D. T. Nguyen, Q. T. Nguyen, S. C. Lam, Analysis ...

1 10 ; S ; [EN] In this paper, estimators of the Nakagami-lognormal (NL) distribution based on the method of log-moments have been derived and thoroughly analyzed. Unlike maximum likelihood (ML) estimators, the log-moment estimators of the NL distribution are obtained using straightforward equations with a unique solution. Also, their performance has been evaluated using the sample mean, confidence regions and normalized mean square error (NMSE). The NL distribution has been extensively used to model composite small-scale fading and shadowing in wireless communication channels. This distribution is of interest in scenarios where the small-scale fading and the shadowing processes cannot be easily separated such as the vehicular environment. This work has been funded in part by the Programa de Estancias de Movilidad de Profesores e Investigadores en Centros Extranjeros de Ensenanza Superior e Investigacion of the Ministerio de Educacion, Cultura y Deporte, Spain, PR2015-00151 and by the Ministerio de Economia, Industria y Competitividad of the Spanish Government under the national project TEC2017-86779-C2-2-R, through the Agencia Estatal de Investigacion (AEI) and the Fondo Europeo de Desarrollo Regional (FEDER). Reig, J.; Brennan, C.; Rodrigo Peñarrocha, VM.; Rubio Arjona, L. (2019). Log-moment estimators of the Nakagami-lognormal distribution. EURASIP Journal on Wireless Communications and Networking. 1-10. https://doi.org/10.1186/s13638-018-1328-6 J. M. Ho, G. L. Stüber, in Co-channel interference of microcellular systems on shadowed Nakagami fading channels. Proc. IEEE 43rd Vehicular Technology Conference, 1993 (VTC 93) (IEEESecaucus, 1993), pp. 568–571. A. A. Abu-Dayya, N. C. Beaulieu, Micro- and macrodiversity NCFSK (DPSK) on shadowed Nakagami-fading channels. IEEE Trans. Commun.42(9), 2693–2702 (1994). X. Wang, W. Wang, Z. Bu, Fade statistics for selection diversity in Nakagami-lognormal fading channels. Electron. Lett.42(18), 1046–1047 (2006). D. T. Nguyen, Q. T. Nguyen, S. C. Lam, Analysis and simulation ...

We fit lognormal distributions to data collected in a national survey for both total water intake and tap water intake by children and adults for these age groups in years: 0 < age < 1; 1 ≤ age < 11; 11 ≤ age < 20; 20 ≤ age < 65; 65 ≤ age; and all people in the survey taken as a single group. These distributions are suitable for use in public health risk assessments.