Search results for "spatial sampling"

showing 2 items of 2 documents

A Proposal to estimate the roaming–dog Total in an urban area through a PPSWOR spatial sampling with sample size greater than two

2018

Settore SECS-S/05 - Statistica SocialeDogs roaming in urban areas constitute an issue for public order hygiene and health. Proper planning of actions for health and security control and allocation of financial funds require the knowledge of the roaming–dog–population size in a given urban area. Unfortunately a reliable statistical procedure aimed to measure such population is not available yet in literature. This paper presents a simple reproducible survey sampling procedure to estimate the number of roaming dogs in an urban area through the description of a real study carried out on a restricted area of the city of Palermo in southern Italy. A sample of areas is drawn by means of a drawn–by–drawn spatial sampling with probabilities proportional to size and without replacement (PPSWOR). As inclusion probabilities are not available in closed form they are estimated by Monte Carlo approach which is of simple implementation and permits design–based variance estimation even when first–order inclusion probabilities are unknown.
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Geostatistics for Mapping Leaf Area Index over a Cropland Landscape: Efficiency Sampling Assessment

2010

This paper evaluates the performance of spatial methods to estimate leaf area index (LAI) fields from ground-based measurements at high-spatial resolution over a cropland landscape. Three geostatistical model variants of the kriging technique, the ordinary kriging (OK), the collocated cokriging (CKC) and kriging with an external drift (KED) are used. The study focused on the influence of the spatial sampling protocol, auxiliary information, and spatial resolution in the estimates. The main advantage of these models lies in the possibility of considering the spatial dependence of the data and, in the case of the KED and CKC, the auxiliary information for each location used for prediction pur…

cropland landscapeleaf area indexScienceQgeostatistics methodsSampling (statistics)GeostatisticsField (geography)KrigingGeneral Earth and Planetary SciencesCommon spatial patternSpatial dependenceLeaf area indexVariogramspatial samplingMathematicsRemote sensingRemote Sensing
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