Results 161 to 170 of about 4,118 (206)
Some of the next articles are maybe not open access.
Spectral Corrected Semivariogram Models
Mathematical Geology, 2006Fitting semivariograms with analytical models can be tedious and restrictive. There are many smooth functions that could be used for the semivariogram; however, arbitrary interpolation of the semivariogram will almost certainly create an invalid function.
Michael J. Pyrcz, Clayton V. Deutsch
openaire +1 more source
Thermal Evaluation to Identify Nodules Using Semivariogram Curves
2021 43rd Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC), 2021Thermography can contribute to the early diagnosis of tumors by identifying nodules that need to be analyzed. The objective of this paper was to verify possible semivariogram curves to identify the possible spatial behavior centered in the region with the nodule and capture the thermal behavioral information surroundings of this point.
Camila Gabriela Grassmann +3 more
openaire +3 more sources
Hybrid Estimation of Semivariogram Parameters
Mathematical Geology, 2007Two widely used methods of semivariogram estimation are weighted least squares estimation and 4 maximum likelihood estimation. The former have certain computational advantages, whereas the 5 latter are more statistically efficient. We introduce and study a "hybrid" semivariogram estimation 6 procedure that combines weighted least squares estimation of ...
Hao Zhang, Dale L. Zimmerman
openaire +1 more source
Stochastic simulation of semivariograms
Journal of the International Association for Mathematical Geology, 1982The semivariogram obtained from simulated space series formed by an autoregressive (AR) process gives a ready explanation for most of the common types. Linear semivariograms arise from a random walk (Brownian motion) process while the transitive and exponential types are generated by an AR process of first order. The continuous (“Gaussian”) type arises
openaire +1 more source
A new class of semiparametric semivariogram and nugget estimators
Computational Statistics & Data Analysis, 2012zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Patrick S. Carmack +5 more
openaire +3 more sources
The semivariogram in remote sensing: An introduction
Remote Sensing of Environment, 1988Abstract The Earth's surface and remotely sensed imagery contain spatial information that, if quantified, could be used to optimize many sampling procedures in remote sensing. Until recently a suitable and simple technique for the spatial characterisation of surfaces was not readily available.
openaire +1 more source
Using Semivariogram Parameter Uncertainty in Hydrogeological Applications
Groundwater, 2009Abstract Geostatistical estimation (kriging) and geostatistical simulation are routinely used in ground water hydrology for optimal spatial interpolation and Monte Carlo risk assessment, respectively. Both techniques are based on a model of spatial variability (semivariogram or covariance) that generally is not known but must be ...
Eulogio, Pardo-Igúzquiza +3 more
openaire +2 more sources
Journal of environmental sciences (China), 2002
The spatial variation of soil nutrients in topsoil (0-20 cm) was analyzed using semivariogram in the Zunhua County of Hebei Province, China. The effect on semivariogram with randomly deleted data and kriged estimates using various reduced sample sizes was also analyzed.
X D, Guo, B J, Fu, K M, Ma, L D, Chen
openaire +1 more source
The spatial variation of soil nutrients in topsoil (0-20 cm) was analyzed using semivariogram in the Zunhua County of Hebei Province, China. The effect on semivariogram with randomly deleted data and kriged estimates using various reduced sample sizes was also analyzed.
X D, Guo, B J, Fu, K M, Ma, L D, Chen
openaire +1 more source
Asymptotic normality of the Nadaraya–Watson semivariogram estimators
TEST, 2007zbMATH Open Web Interface contents unavailable due to conflicting licenses.
openaire +1 more source
A Composite Likelihood Approach to Semivariogram Estimation
Journal of Agricultural, Biological, and Environmental Statistics, 1999This article proposes the use of estimating functions based on composite likelihood for the estimation of isotropic as well as geometrically anisotropic semivariogram parameters. The composite likelihood approach is objective, eliminating the specification of distance lags and lag tolerances associated with the commonly used moment estimator ...
Frank C. Curriero, Subhash Lele
openaire +1 more source