Results 41 to 50 of about 120 (106)

Egg Morphology and Clutch Size in Shrikes (Laniidae) From Historical Oological Collections: Interspecific Patterns and Modest Temporal Change

Ecology and Evolution, Volume 16, Issue 7, July 2026.
Using historical oological collections spanning 1888–1973, we quantified inter‐ and intraspecific variation in egg morphology and clutch size in four shrike species. Among species, egg morphology and clutch size followed a broad size–number trade‐off, with the great grey shrike laying the largest eggs but the smallest clutches, whereas temporal change ...
Paweł Pstrokoński, Katarzyna Roguz, Wojciech Wójcik, Martin Päckert, Joanna Rosenberger, Dominika Mierzwa‐Szymkowiak, Magdalena Sepkowska, Jan Lontkowski, Marek Słupek, Michał Chiliński, Krzysztof Damaziak   +10 more
wiley   +1 more source

Forecasting Count Data With Varying Dispersion: A Latent‐Variable Approach

Journal of Forecasting, Volume 45, Issue 4, Page 1985-2000, July 2026.
ABSTRACT Count data, such as product sales and disease case counts, are common in business forecasting and many areas of science. Although the Poisson distribution is the best known model for such data, its use is severely limited by its assumption that the dispersion is a fixed function of the mean, which rarely holds in real‐world scenarios.
Easton Huch, Candace Berrett, Mason Ferlic, Kimberly F. Sellers   +3 more
wiley   +1 more source

On arbitrarily underdispersed Conway-Maxwell-Poisson distributions

, 2020
We show that the Conway--Maxwell--Poisson distribution can be arbitrarily underdispersed when parametrized via its mean. More precisely, if the mean $μ$ is an integer then the limiting distribution is a unit probability mass at $μ$. If the mean $μ$ is not an integer then the limiting distribution is a shifted Bernoulli on the two values $\floorμ$ and $\
openaire   +2 more sources

Liu Estimation Method in the Zero-Inflated Conway Maxwell Poisson Regression Model

Journal of Statistical Theory and Applications (JSTA)
The Zero-Inflated Conway-Maxwell Poisson Regression Model (ZICPRM) is developed specifically for overdispersed, underdispersed, and excessive zeros in the count data. The ZICMPRM is estimated by the maximum likelihood estimator (MLE).
Muhammad Amin, Bushra Ashraf, Syeda Maryam Siddiqa   +2 more
doaj   +1 more source

Geometric overdispersion facilitates the integration of ecological data

Methods in Ecology and Evolution, Volume 17, Issue 7, Page 2104-2122, July 2026.
Abstract Statistical data integration facilitates inference based on the variety of data prevalent in ecology. In particular, integrated distribution models (IDMs) have been proposed for inferring spatial patterns in abundance using combinations of noisy count, presence–absence and presence–only data.
Justin J. Van Ee, Yoichiro Kanno, Xinyi Lu, Jacob M. Rash, Mevin B. Hooten   +4 more
wiley   +1 more source

Extended Conway-Maxwell-Poisson distribution and its properties and applications [PDF]

Journal of Statistical Distributions and Applications, 2016
A new three parameter natural extension of the Conway-Maxwell-Poisson (COM-Poisson) distribution is proposed. This distribution includes the recently proposed COM-Poisson type negative binomial (COM-NB) distribution [Chakraborty, S. and Ong, S. H. (2014): A COM-type Generalization of the Negative Binomial Distribution, Accepted in Communications in ...
Chakraborty, Subrata, Imoto, Tomoaki
openaire   +3 more sources

Beyond Habitat: How Anuran Skin Texture Shapes Plant Dispersal in Neotropical Wetlands

Freshwater Biology, Volume 71, Issue 7, July 2026.
ABSTRACT Dispersal is a key process structuring wetland plant communities, yet epizoochory by amphibians remains a little‐known mechanism of passive plant dispersal. This study evaluated the potential role of Neotropical anurans as vectors of plant propagules through external adhesion in coastal wetlands.
Andressa Adolfo, Pedro Hoffmann, Andy J. Green, Milena Rosa Pereira, Leonardo F. B. Moreira, Cristina Stenert, Leonardo Maltchik   +6 more
wiley   +1 more source

Modified Kibria–Lukman Estimator for the Conway–Maxwell–Poisson Regression Model: Simulation and Application

Mathematics
This study presents a novel estimator that combines the Kibria–Lukman and ridge estimators to address the challenges of multicollinearity in Conway–Maxwell–Poisson (COMP) regression models.
Nasser A. Alreshidi, Masad A. Alrasheedi, Adewale F. Lukman, Hleil Alrweili, Rasha A. Farghali   +4 more
doaj   +1 more source

Reproductive consequences of mate retention and divorce in a short‐lived migratory passerine

Ibis, Volume 168, Issue 3, Page 1139-1147, July 2026.
In socially monogamous birds, pair‐bond duration varies across species, from single‐breeding associations to long‐lasting, multi‐year bonds. Studies of pair retention and divorce have focused on long‐lived and sedentary species rather than short‐lived and migratory species.
Daniel R. Rodríguez‐Solís, Iraida Redondo, Jesús Martínez‐Padilla, Carlos Camacho, Jaime Potti, David Canal   +5 more
wiley   +1 more source

On Exponential‐Family INGARCH Models

Journal of Time Series Analysis, Volume 47, Issue 4, Page 912-918, July 2026.
ABSTRACT A range of integer‐valued generalised autoregressive conditional heteroscedastic (INGARCH) models have been proposed in the literature, including those based on conditional Poisson, negative binomial and Conway‐Maxwell‐Poisson distributions. This note considers a larger class of exponential‐family INGARCH models, showing that maximum empirical
Alan Huang, Thomas Fung, Kyle Macaskill, Rowan Aukes   +3 more
wiley   +1 more source