Stack Overflow
Stack Overflow

Questions tagged [geostatistics]

43 questions
7
votes
1 answer

Multi-output spatial statistics with gaussian processes

I've been investigating Gaussian processes lately. The perspective of probabilistic multi-output is promising in my field. In particular, spatial statistics. But I encountered three problems: multi-ouput overfitting and anisotropy. Let me run a…
essicolo
  • 803
  • 7
  • 13
3
votes
0 answers

Spatial autocorrelation on a two-dimensional array with missing data

I have some observations collected at sea, and that we managed to classify in 2 clusters (blue and red), based on their properties. As you see in my example below, when projected, the classification looks as "spatially coherent", or at least,…
Alejandro
  • 95
  • 6
3
votes
1 answer

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
  • 33
  • 6
3
votes
1 answer

GAM with "gp" smoother: how to retrieve the variogram parameters?

I am using the following geoadditive model library(gamair) library(mgcv) data(mack) mack$log.net.area <- log(mack$net.area) gm2 <- gam(egg.count ~ s(lon,lat,bs="gp",k=100,m=c(2,10,1)) + s(I(b.depth^.5)) + …
user3036416
  • 1,205
  • 2
  • 15
  • 28
3
votes
2 answers

Underlay a vector image to a grid for kriging in R

After searching around a lot, asking, and doing some code, I kinda got the bare minimum for doing kriging in R's gstat. Using 4 points (I know, totally bad), I kriged the unsampled points located between them. But in actuality, I don't need all of…
ace_01S
  • 387
  • 2
  • 5
  • 16
1
vote
0 answers

Cluster validation and kriging interpolation in R

I am stuck with the kriging interpolation analysis and colour-coding the silhouette output for correct representation of clusters. Any assistance in this regard is greatly appreciated For the kriging, I don't know how to proceed on this. For the…
Taiwo Fakorede
  • 11
  • 1
1
vote
0 answers

How can i reduce the running time when compute variogram for large SaptialPointsDataframe in R

I am a beginner in R and geostatistics. I have a large SpatialPointsDataframe (307,907 elements, 27.2MB). When I want to use this data to build a variogram, it needs a lot of time (R runs for a day without any results). I think this is probably…
Hongyi Lyu
  • 11
  • 1
1
vote
1 answer

Robust Standard Errors in spatial error models

I am fitting a Spatial Error Model using the errorsarlm() function in the spdep library. The Breusch-Pagan test for spatial models, calculated using the bptest.sarlm() function, suggest the presence of heteroskedasticity. A natural next step would…
Orlando Sabogal
  • 1,470
  • 7
  • 20
1
vote
1 answer

Is there an issue with how I'm reading in my shapefile and plotting it?

I've tried to read in my shape file and then plot it but it seems as though RStudio is stuck on something and will not finish running the plot function. Right now I have: library(rgdal) new_county_path <- paste(county_path,…
Buchlord
  • 11
  • 2
1
vote
1 answer

PyKrige witing a file with 3D kriged data

I am trying to krig soil volumes in 3D using pykrige. I am using ordinary kriging, but once I am done kriging the data, I am not sure how I can write it to an ascii file, Here is my code: from pykrige.ok3d import OrdinaryKriging3D from pykrige.uk3d…
Astro
  • 11
  • 1
1
vote
2 answers

Alternative to for-loop for large dataset to improve computational speed

For kriging, I need to compute large mesh arrays of length 20000. The code below works fine, especially for small mesh length (< 100), however, the computational time for such large mesh is very long (approx 45min). The length of data ranges between…
user2554925
  • 487
  • 2
  • 8
1
vote
0 answers

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
  • 753
  • 1
  • 4
  • 12
1
vote
0 answers

How do I fit directional variogram on gridded data, and for a given azimuth return the estimate range?

I have a digital elevation model of topographical features. My overall objective is to make a predictive model by regressing on the range of a directional variogram for a given azimuth. Are there any good python libraries which can accommodate this…
F.Dunbar
  • 37
  • 6
1
vote
0 answers

Get the lag vector from variogram in gstat

I want to compute the variogram from a set of data in R. I am using the function "variogram" from the gstat package. Now, I want to get the lag vector from the variogram. The problem is that myvariogram$dist returns the averages of the distances…
lgndrzzz
  • 288
  • 2
  • 15
1
vote
0 answers

Regression Kriging of binomial data in geoRglm R package

I am using binom.krige() function of the R package geoRglm for determining the spatial predictions of a binary (0, 1) response variable with several continuous as well as discrete covariates. Using glm() with binomial logit link function I found…
Asad Ali
  • 25
  • 6
1
2 3