Ionospheric delay effect is a critical issue that limits the accuracy of precise Global Navigation Satellite System (GNSS) positioning and navigation for single-frequency users, especially in mid- and low-latitude regions where variations in the ionosphere are larger. Kriging spatial interpolation techniques have been recently introduced to model the spatial correlation and variability of ionos...

In simulation, Median Polish Kriging is a technique used to predict unobserved data points in two-dimensional space. The linear behavior of the traditional Median Polish Kriging in the estimation of the mean function in a high grid makes the interpolation of O(1) which has a low order in the prediction and that leads to a high prediction error. Therefore, an improvement in the estimation of the...

the measurement of wheat crop yield in large areas is time consuming and requires high expenses. one way to save time and cost, using geostatistical methods for mapping crop yield. in this research principle component analysis were used for identifying variables that have correlation with each other, and kriging and cokriging were used to map crop yield prediction. fourty six samples were used ...

in this study, the effects of long term use of urban wastewater (over 40 years) on soil salt content and related parameters were evaluated in the lands south of tehran. for this analysis, kriging methods were tested. according to the suitable model indices, ordinary kriging (ok) was suitable for ph, clay, na+, mg2+ and sodium adsorption ratio (sar) interpolation; log-normal kriging (log-normal ...

This research studies the spatial distribution quality of interpolation methods. The aims first to obtain unbiased estimator parameters based on regionalized variables in study field. We used kriging techniques (called Local interpolation) rely variogram function with a fuzzy inference system, where is an extension ordinary kriging. second objective this work estimate covariance models real dat...

Two widely used methods of semivariogram estimation are weighted least squares estimation and maximum likelihood estimation. The former have certain computational advantages, whereas the latter are more statistically efficient. We introduce and study a “hybrid” semivariogram estimation procedure that combines weighted least squares estimation of the range parameter with maximum likelihood estim...

BACKGROUND Disease maps of crude rates from routinely collected health data indexed at a small geographical resolution pose specific statistical problems due to the sparse nature of the data. Spatial smoothers allow areas to borrow strength from neighboring regions to produce a more stable estimate of the areal value. Geostatistical smoothers are able to quantify the uncertainty in smoothed rat...

Sampling and estimation of geographical attributes that vary across space (e.g., area temperature, urban pollution level, provincial cultivated land, regional population mortality and state agricultural production) are common yet important constituents of many real-world applications. Spatial attribute estimation and the associated accuracy depend on the available sampling design and statistica...