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Spatial Sampling Design For Parameter Estimation Of The Covariance Function, Zhengyuan Zhu, Michael L. Stein Sep 2005

Spatial Sampling Design For Parameter Estimation Of The Covariance Function, Zhengyuan Zhu, Michael L. Stein

Zhengyuan Zhu

We study the spatial optimal sampling design for covariance parameter estimation. The spatial process is modeled as a Gaussian random field and maximum likelihood (ML) is used to estimate the covariance parameters. We use the log determinant of the inverse Fisher information matrix as the design criterion and run simulations to investigate the relationship between the inverse Fisher information matrix and the covariance matrix of the ML estimates. A simulated annealing algorithm is developed to search for an optimal design among all possible designs on a fine grid. Since the design criterion depends on the unknown parameters, we define relative …


New Developments In The Behavioral Ecology And Conservation Of Ruffed Lemurs (Varecia), Natalie Vasey May 2005

New Developments In The Behavioral Ecology And Conservation Of Ruffed Lemurs (Varecia), Natalie Vasey

Natalie Vasey

The papers in this issue were presented at a symposium during the 25th Annual Meeting of the American Society of Primatologists held in Oklahoma City, Oklahoma, in June 2002. This symposium brought together many of the scientists who have contributed to our knowledge of ruffed lemur ecology, behavior, and conservation in the past decade. One objective was to share and compare key findings about ruffed lemurs (Varecia) resulting from long-term field studies at various sites in Madagascar. A second objective was to cross-fertilize work being done in the wild with that being done in captivity, with the aim of advancing …


National Park Service Southwest Alaska National Parks Visitor Impact Monitoring: Phase 1 Report, Christopher Monz, P. D'Luhosch Jan 2005

National Park Service Southwest Alaska National Parks Visitor Impact Monitoring: Phase 1 Report, Christopher Monz, P. D'Luhosch

Christopher Monz

No abstract provided.


Severe Wind And Fire Regimes In Northern Forests: Historic Variability At The Regional Scale, Lisa A. Schulte-Moore, David J. Mladenoff Jan 2005

Severe Wind And Fire Regimes In Northern Forests: Historic Variability At The Regional Scale, Lisa A. Schulte-Moore, David J. Mladenoff

Lisa A. Schulte Moore

Within the northern Great Lakes region, mesoscale (10s to 100s of km2) forest patterning is driven by disturbance dynamics. Using original Public Land Survey (PLS) records in northern Wisconsin, USA, we study spatial patterns of wind and fire disturbances during the pre-Euroamerican settlement period (ca. 1850). Our goals were: (1) to determine how effectively wind and fire disturbance can be econstructed from the PLS, (2) to assess the roles of wind and fire in shaping vegetation patterns, (3) to evaluate landscape to regional controls of wind and fire regimes, and (4) to assess the potential for interactions between these disturbances. …


Microbial Diversity In Hot Spring Cyanobacterial Mats: Pattern And Prediction, Frederick M. Cohan, D. M. Ward Dec 2004

Microbial Diversity In Hot Spring Cyanobacterial Mats: Pattern And Prediction, Frederick M. Cohan, D. M. Ward

Frederick M. Cohan

No abstract provided.