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Questions tagged [covariogram]

Covariogram is a variogram/plot of the covariance or the extremal coefficient functions and the practical range estimated fitting a Gaussian (or can be a max-stable random) field with the composite-likelihood or by using the weighted least square method.

Covariogram is a variogram/plot of the covariance or the extremal coefficient functions and the practical range estimated fitting a Gaussian (or can be a max-stable random) field with the composite-likelihood or by using the weighted least square method.

Example from upenn university

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R: Calculate sill, range and nugget from a raster object

I need to calculate the sill, range and nugget from a raster layer. I have explored gstat, usdm packages where one can create variogram however I couln't find a function which given a raster layer will estimate these parameters.In most of the…
Arihant
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how to change the lag distance while calculating a Variogram in R

I am trying to calculate an Experimental-Variogram value at different lag distances, so I am using the variogramm command variog1 <- variogram((Copper)~1,ds) but I can't know how to specify the needed lag distance. For example I want to get a…
Ahmed Emam
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Fast, elegant way to calculate empirical/sample covariogram

Does anyone know a good method to calculate the empirical/sample covariogram, if possible in Python? This is a screenshot of a book which contains a good definition of covariagram: If I understood it correctly, for a given lag/width h, I'm supposed…
r_31415
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How is variogramST dealing with distance and time?

I'm new in spatio-temporal analysis in r so I don't know if what I'm doing is right. I have a lot of spatio-temporal data and I would like to plot a spatio-temporal sample variogram. My problem is that I don't really understand how variogramST…
AliceW
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R variogram plot in lme vs lm?

If I use the lme function in the package nlme and write m <- lme(y ~ Time, random = ~1|Subject) and then write Variogram(m, form = ~Time|Subject) it produces the variogram no problem. However, if I use lm without the random effect, m <- lm(y ~…
Jaood
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How to convert a dataframe into a gstat object in R? Specifically a gstatVariogram

I'd like to create a variogram fit from some semivariance data in R. I realize that a variogram fit requires an object generated by vgm, and raw.vgm gneerated by variogram, for example: x = seq(0,300,by=300/100) y = seq(0,0.9,by=(0.9/100)) Z =…
makansij
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How to create a variogram

I'm a new user of R, which I use in my studies in digital soil mapping. I have my data, as you can see in my .csv file. There are columns SN (sample number), SAND, SILT, CLAY, OM (Organic Matter). I am trying to create a variogram for each property.…
Dimitris K
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Nugget value is always zero while using scikit-geostat

import numpy as np import skgstat as skg coordinates = long_data values =N_data V = skg.Variogram(coordinates=coordinates, values=values ,maxlag=np.max(dists)/2.0 , use_nugget =True ) print(V) V.plot() enter image description here from the graph…
Nikhil Dupally
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My variogram code result different from variog() result

I am writing code for producing a variogram. For validating my result, I checked with geoR::variog() but both variograms are different. I tried to understand the code of variog() to see what happens under the hood but there are so many things…
Prakkash Manohar
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Obtaining theoretical semivariogram from parametrized covariance function (STK)

I have been using the STK toolbox for a few days, for kriging of environmental parameter fields, i.e. in a geostatistical context. I find the toolbox very well implemented and useful (big thanks to the authors!), and the kriging predictions I am…
mdh
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variogram range is not unique within some specific degree

variogram of the dataset I got this variogram from a set of spatial temporal data, but i am wondering why the 90 degree have such a 'small' range compare to other, is it my data problem or I can adjust some setting in the…
vincentchau
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R version 3.3.2, Windows 10: gstat package: Error in fitting a variogram model using 'fit.variogram' function

I am having some problem with fit.variogram function of the gstat package. My code, data, error message and traceback() message can be found below. Any suggestion to approach this problem would be appreciated.…
Saubhagya
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Simple variogram in R, understanding gstat::variogram() and object gstat

I have a data.frame in R whose variables represent locations and whose observations are measures of a certain variable in those locations. I want to measure the decay of dependence for certain locations depending on distance, so the variogram comes…
D1X
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Create variogram in R's gstat package

Suppose I have rainfall data taken at four weather stations over the span of 2004-2016. I fed the data into a database for retrieval in R. My goal is to take the data for every single day from that period, and krige using those values,…
ace_01S
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Error in xy.coords(x, y, xlabel, ylabel, log) : 'x' is a list, but does not have components 'x' and 'y'

I try to plot the variogram in R. When I run the below code: library(geoR) Data = as.geodata(Data2, coords.col=1:2, data.col=3) VG = variog(Data2,estimator.type="classical") VG.fit = variofit(VG, ini.cov.pars =c(0.095,1.4), cov.model="gaussian", …
Peter M Macharia
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