Results 171 to 180 of about 222,822 (188)

Poisson-Lognormal Distributions

2018
The Poisson-lognormal distribution was suggested as a model for commonness of species by Preston. The analysis leading him to suggest this distribution was as follows: Suppose that the number of each species caught in a trap is assumed to be a single sample from a Poisson distribution with mean λ. R. S. Uhler and P. G.
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Density approximations and VaR computation for compound Poisson-lognormal distributions

Communications in Statistics - Simulation and Computation, 2015
ABSTRACTParametric approximations of the compound Poisson-lognormal distribution are developed and used to compute Value-at-Risk (VaR). As guidelines for finding an approximation, the skewness–kurtosis space and the tail behavior are considered. The Generalized Beta distribution of the second kind (GB2) and a mixture of lognormals are found to provide ...
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Retention for Stoploss reinsurance to minimize VaR in compound Poisson-Lognormal distribution

AIP Conference Proceedings, 2015
Automobile insurance is one of the emerging general insurance’s product in Indonesia. Fluctuation in total premium revenues and total claim expenses leads to a risk that insurance company can not be able to pay consumer’s claims, thus reinsurance is needeed.
Achmad Zanbar Soleh, Lienda Noviyanti, Irma Nurrahmawati   +2 more
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Critical elements on fitting the Bayesian multivariate Poisson Lognormal model

AIP Conference Proceedings, 2015
Motivated by a problem on fitting multivariate models to traffic accident data, a detailed discussion of the Multivariate Poisson Lognormal (MPL) model is presented. This paper reveals three critical elements on fitting the MPL model: the setting of initial estimates, hyperparameters and tuning parameters.
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Analyzing Spatial Structure of Communities Using the Two‐Dimensional Poisson Lognormal Species Abundance Model

American Naturalist, 2002
The joint spatial and temporal fluctuations in the community structure of tropical butterflies are analyzed by fitting the bivariate Poisson lognormal distribution to a large number of observations in space and time. By applying multivariate dependent diffusions for describing the fluctuations in the abundances, the environmental variance is estimated ...
Steinar Engen, Russell Lande, Philip J Devries   +2 more
exaly   +3 more sources

Bayesian Multivariate Poisson Lognormal Models for Crash Severity Modeling and Site Ranking

Transportation Research Record: Journal of the Transportation Research Board, 2009
Traditionally, highway safety analyses have used univariate Poisson or negative binomial distributions to model crash counts for different levels of crash severity. Because unobservables or omitted variables are shared across severity levels, however, crash counts are multivariate in nature.
Jonathan Aguero-Valverde, Paul P. Jovanis   +1 more
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Comparison of Poisson, Negative Binomial and Poisson-Lognormal Regression Models With Application on Traffic Road Accident Count Data of Bauchi State

BIMA JOURNAL OF SCIENCE AND TECHNOLOGY GOMBE
Road Traffic Crash has been a serious problem on major roads in Nigeria. Different models have been used to predict accident on these roads but no unique model has been arrived at. In this article, three statistical models: Poisson Regression, Negative Binomial and the Poisson Lognormal were compared to determine the best fit on the road accident data ...
Ofunu , Ben Esther, Abdulkadir, S.S., Abdulkadir , Ahmed   +2 more
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Full Bayes Poisson gamma, Poisson lognormal, and zero inflated random effects models: Comparing the precision of crash frequency estimates

Accident Analysis & Prevention, 2013
In recent years, complex statistical modeling approaches have being proposed to handle the unobserved heterogeneity and the excess of zeros frequently found in crash data, including random effects and zero inflated models. This research compares random effects, zero inflated, and zero inflated random effects models using a full Bayes hierarchical ...
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Mixtures of contaminated multivariate Poisson-lognormal models

2023
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Statistical Analysis of Spatial Distribution of External Corrosion Defects in Buried Pipelines Using a Multivariate Poisson-Lognormal Model

Structure and Infrastructure Engineering, 2021
Xiangrong Wang, Fujian Tang, Hui Wang
exaly