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Assessing Map Accuracy in a Remotely Sensed, Ecoregion-Scale Cover Map

Thomas C. Edwards, Gretchen G. Moisen, D.Richard Cutler
1998 Remote Sensing of Environment  
As part of our design process, we first reviewed the effect of intracluster correlation and a simple cost function on the relative efficiency of cluster sample designs to simple random designs.  ...  We close with a discussion of the logistical constraints facing attempts to assess the accuracy of large area, remotely-sensed cover-maps.  ...  As part of our design process, we first reviewed the effect of intracluster correlation and a simple cost function on the relative efficiency of cluster sample designs to simple random designs.  ... 
doi:10.1016/s0034-4257(96)00246-5 fatcat:wuuklbsv2vbdzgrde5ep3ixm5e

Stratified sampling in fruit orchards using cluster-based ancillary information maps: a comparative analysis to improve yield and quality estimates

Asier Uribeetxebarria, José A. Martínez-Casasnovas, Alexandre Escolà, Joan R. Rosell-Polo, Jaume Arnó
2018 Precision Agriculture  
Stratified sampling in fruit orchards using cluster-based ancillary information maps: a comparative analysis to improve yield and quality estimates. Precis.Agric.  ...  Specifically, given the results of a stratified random sample, an unbiased estimator of the variance of the mean for a simple random sample from the same population is (Eq. 7), ( ) ( ) ( ) * ∑ ∑ ( ) +  ...  2018) , the spatial variation of ECa could make it advisable to stratify on the basis of this information layer instead of using an NDVI map.  ... 
doi:10.1007/s11119-018-9619-9 fatcat:tyjvc3gugfg4lefssciqhdmge4

Stand dynamics, spatial pattern and site quality in Austrocedrus chilensis forests in Patagonia, Argentina

S.L. Burns, J.F. Goya, M.F. Arturi, P.F. Yapura, C.A. Pérez
2013 Forest Systems  
Main results: Both sites exhibited a random spatial distribution of A. chilensis but different processes seem to underlie the patterns.  ...  Dead individuals by diameter class were compared by means of a chi square test. Spatial distribution pattern was analyzed using the pair-correlation function and the mark-correlation function.  ...  Acknowledgements This research was supported by funding from the Universidad Nacional de La Plata and from the Inter-national Foundation for Science (IFS).  ... 
doi:10.5424/fs/2013222-02834 fatcat:l3uttbjh6zgzvby3vpc6hylh7q

STATISTICAL SIMULATION OF 2D RANDOM FIELD WITH CAUCHY CORRELATION FUNCTION IN THE GEOPHYSICS PROBLEM OF ENVIRONMENT MONITORING

Z. Vyzhva, V. Demidov, A. Vyzhva, K. Fedorenko
2017 Visnyk. Geology  
In this case a problem was occurred to supplement simulated data that were received at the control of chalky strata density changes at the research industrial area with use of radioisotope methods on a  ...  This problem was solved in this work by statistical simulation method that provides the ability to display values (random field on a plane) in any point of the monitoring area.  ...  random field on a plane) in any point of the monitoring area.  ... 
doi:10.17721/1728-2713.76.13 fatcat:45vgcfur7bg73nelqqbzof54su

STATISTICAL SIMULATION OF RANDOM FIELD ON 2D AREA WITH WHITTLE-MATERN TYPECORRELATION FUNCTION IN THE GEOPHYSICAL PROBLEM OF ENVIRONMENT MONITORING
СТАТИСТИЧНЕ МОДЕЛЮВАННЯ ВИПАДКОВОГО ПОЛЯ НА ПЛОСКІЙ ОБЛАСТІ З КОРЕЛЯЦІЙНОЮ ФУНКЦІЄЮ ТИПУ УІТТЛІ–МАТЕРНА В ГЕОФІЗИЧНІЙ ЗАДАЧІ МОНІТОРИНГУ ДОВКІЛЛЯ

Z. Vyzhva, V. Demidov, A. Vyzhva
2019 Visnyk. Geology  
This problem was solved in this work by statistical simulation method that provides the ability to display values (the random field of a research object on a plane) in any point of the monitoring area.  ...  In this case a problem occurred to supplement simulated data that were received at the control of chalky strata density changes at the research industrial area with use of radioisotope methods on a grid  ...  The difference between the map of input density values and the trend is a homogeneous isotropic random field in most cases.  ... 
doi:10.17721/1728-2713.86.08 fatcat:6nslcny4wzebxiz3bia54vl4hu

Stratification by Rank-1 Lattices [chapter]

Alexander Keller
2004 Monte Carlo and Quasi-Monte Carlo Methods 2002  
Based on rank-1lattices we present a new slratification technique that removes this dependency on dimension, is much more efficient by correlation, is trivial to implement, and robust to use.  ...  So far only uncorrelated stratification methods were used that in addition depend on the dimension of the integration domain.  ...  connection with e.g. the solution of partial differential equations and the Fourier transforrn on rank-1-lattices [Keller 2001 ).  ... 
doi:10.1007/978-3-642-18743-8_18 fatcat:3tusplunizfblmp5qfzrlon7kq

Use of soil-map delineations to improve (Co-)kriging of point data on moisture deficits

A. Stein, M. Hoogerwerf, J. Bouma
1988 Geoderma  
Stein, A., Hoogerwerf, M. and Bouma, J., 1988 . Use of soil-map delineations to improve (co-) kriging of point data on moisture deficits. Geoderma, 43: 163-177.  ...  In unstratified maps the standard deviation of the prediction error largely depends on the observation pattern.  ...  Corsten from the Department of Mathematics of the Agricultural  ... 
doi:10.1016/0016-7061(88)90041-9 fatcat:bvnrdku7a5fifhxhk3zvg4hefy

Theory of general balance applied to step wedge designs

Simon Bond
2018 Statistics in Medicine  
It provides a calculus to decompose the implied covariance structure into orthogonal strata, with three different parametrisations that correspond to expected sums of squares, variance parameters of random  ...  Estimates from different strata have the useful property of mutual independence, conditional on the true values, and the covariance decomposition immediately provides expressions for the variance of each  ...  The parametrisation considered above adds on a point mass of extra correlation for observations in the same cluster and period.  ... 
doi:10.1002/sim.7960 pmid:30209821 fatcat:xvtp7x5lybad3psgmhutjruszm

Issues in the mapping of two diseases

Alan R Dabney, Jon C Wakefield
2005 Statistical Methods in Medical Research  
In this article, we consider a number of issues relating to such an endeavour including the standardization process and the comparison of univariate and bivariate disease mapping models.  ...  A principle motivation for the examination of two or more diseases is to discover similarities or dissimilarities in the geographical distribution of risk.  ...  Acknowledgements The authors would like to thank Richard Hoskins of the Washington State Department of Health for many useful discussions and for help in obtaining the incidence data used in the article  ... 
doi:10.1191/0962280205sm340oa pmid:15691001 fatcat:r3ep36foijgzxjn7xz2msjixca

Assessing Landbird Monitoring Programs and Demographic Causes of Population Trends

James F. Saracco, David F. Desante, Danielle R. Kaschube
2008 Journal of Wildlife Management  
We included the number of young per adult captured (an index of productivity) as a covariate in models to assess effects of productivity on trends.  ...  We suggest that increased MAPS coverage, better coordination between MAPS and the BBS, and continued development of analytical methods that link the 2 programs will enhance the value of these monitoring  ...  Concordance between the BBS and MAPS also suggests that MAPS data are representative of real populations despite distributions of stations that are not completely random.  ... 
doi:10.2193/2008-129 fatcat:tniz3uycbbctjjhldzminh7dda

Which is the optimal sampling strategy for habitat suitability modelling

Alexandre Hirzel, Antoine Guisan
2002 Ecological Modelling  
In order to compare them, a virtual species approach (Ecol. Model. 145 (2001) 111) in a real landscape, based on reliable data, was chosen.  ...  The sampled data were then fed into a GLM to make two types of prediction: (1) habitat suitability and (2) presence/ absence.  ...  Aspinall and Michele Scardi for their useful comments on an earlier version of the manuscript, and Julie Warrillow for her kind linguistic revision.  ... 
doi:10.1016/s0304-3800(02)00203-x fatcat:d6zolcacavgkhppa42fyz4x7iy

Detecting the influence of rare stressors on rare species in Yosemite National Park using a novel stratified permutation test

J. R. Matchett, Philip B. Stark, Steven M. Ostoja, Roland A. Knapp, Heather C. McKenny, Matthew L. Brooks, William T. Langford, Lucas N. Joppa, Eric L. Berlow
2015 Scientific Reports  
We present a novel approach for inferring influence of a rare stressor on a rare species by blending predictive models with nonparametric permutation tests.  ...  Our approach confirms the known negative relationship between fish and R. sierrae, but finds no evidence of a negative relationship between current packstock use and A. canorus breeding.  ...  Acknowledgements We thank dozens of field assistants for their invaluable help with amphibian surveys for both R. sierrae and A. canorus.  ... 
doi:10.1038/srep10702 pmid:26031755 pmcid:PMC4451553 fatcat:huishgjmlrd4joh5bxn3jq7pdy

SPATIAL STATISTICS FOR ESTIMATING SAGO STOCK IN WEST PAPUA, INDONESIA = Statistika Spasial untuk Estimasi Stok Sagu di Papua Barat, Indonesia

Mubekti .
2016 Jurnal Teknologi Lingkungan  
Kata Kunci : statistik spasial, area kerangka sampling, penginderaan jauh, sagu sawitAbstractSago palm is one of Genus Metroxylon belonging to Family Palmae, that accumulates a huge amount of starch in  ...  The Objective of this study is to develop spatial statistics method for mapping and estimating sago stock in Inanwatan District,Sorong Selatan Regency, West Papua.  ...  Systematic random sampling rules are used to extract 0,5 % sample segment, then the extracted sampel segments is overlaid with strata map.  ... 
doi:10.29122/jtl.v14i2.1427 fatcat:5jz5vfl7ezeyzkeyagbfdqi7k4

Construction and Use of a Simple Index of Urbanisation in the Rural–Urban Interface of Bangalore, India

Ellen Hoffmann, Monish Jose, Nils Nölke, Thomas Möckel
2017 Sustainability  
Later on, it will also provide a matrix against which the results can be aligned and evaluated.  ...  The correlation of the two parameters and discontinuities in the frequency distribution of the combined index indicate highly dynamic stages of transformation, spatially clustered in the rural-urban interface  ...  Mapping of SSI, morphological classes, and structural strata in the Northern transect.  ... 
doi:10.3390/su9112146 fatcat:5i4qf4rps5cujo7ha5uvfx5mju

Spatially stratified sampling using auxiliary information for geostatistical mapping

Matthew G. Falk, Robert J. Denham, Kerrie L. Mengersen
2009 Environmental and Ecological Statistics  
Each of the samples for the two data sets is interpolated using regression kriging to form a geostatistical map for their respective areas.  ...  The sampling technique is compared to other design-based approaches including simple random sampling, systematic sampling on a regular grid, conditional Latin Hypercube sampling and stratified sampling  ...  Then a simple random sample of n k is taken from each strata, such that n = k n k . The sample sizes n k depend on the aim of the subsequent analysis.  ... 
doi:10.1007/s10651-009-0122-3 fatcat:rlt3734fffhhvml6hhofbhfj44
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