Results 41 to 50 of about 1,618,729 (319)

Network topology drives population temporal variability in experimental habitat networks

Population Ecology, EarlyView.
Habitat patches connected by dispersal pathways form habitat networks. We explored how network topology affects population outcomes in laboratory experiments using a model species (Daphnia carinata). Central habitat nodes in complex lattice networks exhibited lower temporal variability in population sizes, suggesting they support more stable ...
Yiwen Xu, J. Angus Webb, William D. Bovill, Elise L. King   +3 more
wiley   +1 more source

Two Novel Two-Stage Direction of Arrival Estimation Algorithms for Two-Dimensional Mixed Noncircular and Circular Sources

Sensors, 2017
This paper addresses the two-dimensional (2D) direction-of-arrival (DOA) estimation problem with two novel methods for mixed noncircular and circular signals.
Heping Shi, Wen Leng, Zhiwei Guan, Tongzhi Jin   +3 more
doaj   +1 more source

Two-stage sampling in the estimation of growth parameters and percentile norms: sample weights versus auxiliary variable estimation

BMC Medical Research Methodology, 2021
Background The use of auxiliary variables with maximum likelihood parameter estimation for surveys that miss data by design is not a widespread approach, despite its documented improved efficiency over traditional approaches that deploy sampling weights.
George Vamvakas, Courtenay Norbury, Andrew Pickles   +2 more
doaj   +1 more source

A Comparison of Two-Stage Least Squares (TSLS) and Ordinary Least Squares (OLS) in Estimating the Structural Relationship between After-School Exercise and Academic Performance

Mathematics, 2021
The current study examines the structural relationship between the academic performance exam scores of Korean middle school students and their after-school exercise hours.
Kyulee Shin, Sukkyung You, Mihye Kim
doaj   +1 more source

Two-Stage Maximum Score Estimator

, 2020
This paper considers the asymptotic theory of a semiparametric M-estimator that is generally applicable to models that satisfy a monotonicity condition in one or several parametric indexes. We call the estimator two-stage maximum score (TSMS) estimator since our estimator involves a first-stage nonparametric regression when applied to the binary choice
Gao, Wayne Yuan, Xu, Sheng, Xu, Kan
openaire   +2 more sources

occumb: An R package for site occupancy modeling of eDNA metabarcoding data

Population Ecology, EarlyView.
This study introduces a new R package, occumb, for the convenient application of site occupancy modeling using environmental DNA (eDNA) metabarcoding data. We outline a data analysis workflow, including data setup, model fitting, model assessment, and comparison of potential study settings based on model predictions, all of which can be performed using
Keiichi Fukaya, Yuta Hasebe
wiley   +1 more source

Remaining Useful Life Estimation for Rolling Bearing With SIOS-Based Indicator and Particle Filtering

IEEE Access, 2018
Rolling bearing is a key component of rotating machinery, and its remaining useful life (RUL) estimation is also a critical technique in prognostics health management activities.
Mingquan Qiu, Wei Li, Fan Jiang, Zhencai Zhu   +3 more
doaj   +1 more source

Two-Stage Plans for Estimating the Inverse of a Monotone Function [PDF]

Technometrics, 2015
This study investigates two-stage plans based on nonparametric procedures for estimating an inverse regression function at a given point. Specifically, isotonic regression is used at stage one to obtain an initial estimate followed by another round of isotonic regression in the vicinity of this estimate at stage two.
Runlong Tang, Shawn Mankad, Moulinath Banerjee, George Michailidis   +3 more
openaire   +2 more sources

Between Droughts and Floods: The Seasonal Response of Freshwater Snails in Artificial Reservoirs in the Brazilian Semiarid Region

Population Ecology, EarlyView.
We investigate the seasonal dynamics of two freshwater snails, Biomphalaria straminea and Melanoides tuberculata, in artificial reservoirs of the Brazilian semiarid region. Despite regulated hydrology, B. straminea exhibited strong seasonal fluctuations associated with dry periods, while M. tuberculata maintained stable populations throughout the year,
Lucas Henrique Sousa da Silva, João Hemerson de Sousa, Adriana Josefa da Rocha, Manuella Feitosa Leal, Lucas Ariel de Sousa Aguiar, Tamaris Gimenez Pinheiro, Edson Lourenço da Silva   +6 more
wiley   +1 more source

Infection Models for Pine Wilt Disease on the Basis of Vector Behaviors

Population Ecology, EarlyView.
Infection models for pine wilt disease without vector density were built to estimate the transmission coefficient of the pathogenic nematode. The models successfully simulated the annual change in the density of infected trees for four pine stands. ABSTRACT Pine wilt disease is caused by the pinewood nematode (Bursaphelenchus xylophilus Steiner et ...
Katsumi Togashi
wiley   +1 more source