[edit] Variogram Models
The empirical variogram cannot be computed at every lag distance h and due to variation in the estimation it is not ensured that it is a valid variogram, as defined above.
semivariogram
See Also: variogram
[spatial statistics (use for geostatistics)] The variogram divided by two.
Semivariogram/Covariance surface
Anisotropy
Specifying or estimating the proportion of measurement error in the nugget
Cross-covariance option for shift between variables ...
Sampling variogram
Spatial dependence
Variogram
Multiple-indicator kriging ...
Figure 4. Variogram model fitted to the residuals of the fitted large-scale model.
When predicting the small-scale term for a location , constrained kriging (Cressie 1993) was used. Ordinary kriging involves the constraint ...
Figure 4.1.2-1. Variogram plot depicts the relationship between distance and measurement similarity (spatial autocorrelation).
That is the estimates can be biased due to the inappropriate choise of the trend expression and the regular model for variogram approximation.
methods: histogram, voronoi map, normal QQplot, general QQPlot, trend analysis, semivariogram/covariance cloud, crosscovariance cloud) ...
Spatial autocorrelation can be analyzed using correlograms, covariance functions and variograms (=semivariograms).
References: ...
are Linear interpolation, which effectively runs a straight line between the points with altitude values, the Cubic Spline, which interpolates a smooth curve through the given data points, and Statistical interpolation using Kriging semi-variograms.
 See also: Model, Information, Analysis, GIS, Surface
|
