The field of study concerning statistical methods that use space and spatial relationships (such as distance, area, volume, length, height, orientation, centrality and/or other spatial characteristics of data) directly in their mathematical computations.

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Choropleth / thematic map in R with ggplot2 not filling polygons [migrated]

I am doing the following: I read a shapefile containing boundaries within a city (Leeds for example), then I read another data set (csv.) containing the number of females in each area for which I ...
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19 views

Incorporating systematic error in (spatial) predictive modelling

I have created a model (random forest) and withheld 20%. When I apply the model to the withheld dataset and check the residuals against the real values I can see there is a systematic error e.g lower ...
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1answer
16 views

Mantel test and Moran I giving different result for same data sample

I want to check spatial correlation for my data about fecal coliform values in water measured at different location. For this I have tried both Moran.I and the Mantel test. They are giving different ...
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5 views

What is the spatial coupling in a random field? [closed]

What is the meaning of "spatial coupling of grid nodes" in a random field ?
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21 views

Does negative binomial regression assume sample independence?

I'm working with a negative binomial multiple regression and I'm wondering about the assumption of spatial independence of samples. White and Bennetts (1996) say that the assumption of spatial ...
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27 views

Interpretation of scaled data in a logistic regression analysis

I have a variable (distance to road; measurement=meters; see below) that contains a right-skew and percentage data (0-100% based on amount of habitat in a moving window; see example below) in a ...
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39 views

Manual two-way demeaning panel data in R

I'm trying to manually demean panel data by both time demeaning and cross-sectional demeaning, yet haven't been able to do it well. The best thing I can think of is looping through the means for each ...
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9 views

How do I demonstrate threshold proximity between the movement of one object on another?

I'm hoping you can advise on what may be a very simple problem. Here's the scenario: I have several maps of an estuary, each separated by ten years from the last. On each map are two variables: ...
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1answer
99 views

Feasibility of Negative Binomial Spatial Regression

I have a set of crime count data where it appears that the data take on a negative binomial distribution. I have had some success converting the dependent variable (a crime count) into a rate and then ...
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1answer
32 views

What to make of countervailing spatial regression coefficients?

I am running regressions across a country's counties (N about 300). I divide the country in two regions A and B to control for potential unobservables. My explanatory variable varies at the county ...
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26 views

how to bootstrap data on irregular grid?

I have irregular gridded data and I wish to resample from this data in such a way that the spatial correlation in the data is preserved. I will assume that grids that are within 300Kms of one another ...
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1answer
19 views

Learning a spatial function

I have some observations of a variable y, that varies spatially. For each observation, I also have a lat, long tuple. I have some 50 or so observations. Besides conducting some exploratory analysis ...
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30 views

Testing whether neighbors are more similar to each other than distant points

Suppose you have points x1...xn in a metric space X, each is associated with some measurement y1...yn. I want to test whether points closer to each other in X have similar associated value y. I have ...
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15 views

Difference between spatially autocorrelated logit methods

I am seeking advice on different methods to account for spatial autocorrelation in logit models. I've seen a lot of different models attempt to address all of the issues with spatial logit models ...
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31 views

Calculate prediction interval for SAR model (errorsarlm function in R)

I would like to predict prediction interval for a SAR model (function errorsarlm in R - package spdep). While the function predict.lm allows to set interval='prediction' parameter to predict the upper ...
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17 views

Testing causes of accident blackspots on road network

Say I have a way of predicting, for each link on a network, the likelihood of road accidents. I also have a (mercifully quite sparse) point data set of recorded accidents. Bearing in mind that the ...
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31 views

Measurament error from semivariogram

I am looking at a model to determine the measurement error for a set of measurements of a spatially correlated phenomenon (sea surface temperature measurements) using a semivariogram technique. For ...
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20 views

How can I evaluate spatial autocorrelation in a binomial GLMM?

Following Dormann et al 2007 Ecography, I have employed a GLMM approach in R to account for spatial autocorrelation in a binomial regression model (logistic regression) that does not have random ...
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1answer
42 views

Is it valid to use a model-variogram fit not on the full range of lag distance?

I am trying to implement a form of 2 stage least squares, in step 1 I ignored the spatial correlation between the observations, now in step 2 I look at the spatial correlation of the residuals of step ...
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1answer
111 views

Intrinsic spatial stationarity: doesn't it only apply for small lags?

From the definition of Intrinsic stationarity: $E[Z(x)-Z(x-h)] = 0$ This assumption is used for example in ordinary kriging, instead of assuming a constant mean over the entire space, we assume the ...
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9 views

Classification for series of lat, lon points of varying lengths

I have a dataset of series of latitude and longitude points. Each series of points corresponds to some activity. The number of latitude/longitude points is not the same for the series. My dataset ...
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24 views

Universal kriging: which variogram to use?

I am working with the build in dataset meuse, which has 155 measurements of Zinc and the distance to the river "Meuse".(http://rspatial.r-forge.r-project.org/gallery/). Now I am trying to imitate ...
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1answer
36 views

How to use geometric proximity in classification

I am doing a classification of certain regions of an image. Let's say I have done the classification, and some classes have been classified positively (negatively) with high probability. For my ...
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1answer
69 views

Correcting for spatial autocorrelation in dissimilarity datasets

I have a community assembly dataset with 299 species at 15 sites. Im interested in correcting for the effect of spatial autocorrelation on beta-diversity (or species turnover). Dataset here. There is ...
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Multiple Imputation for Spatial Models

I'm trying to estimate various spatial models (SAR, SDM, SEM) but have missing data throughout my variables. The mice package in R gives a straightforward solution when none of the variables with a ...
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2answers
33 views

Direct parametrization of Cholesky decomposition of spatial covariance matrix

In spatial data analysis, a simple way to model the covariance stucture between spatial observations is via a covariance function like $cov(y_i,y_j) = C e^{-rD_{ij}}$, based on some (euclidean) ...
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1answer
40 views

PDF of Distance between the centre of a regular hexagon of radius R and any point within it

What is the probability distribution function of the distnace between the centre of a regular hexagon of radius R and any point within it? I have done the following and would appreciate if you could ...
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1answer
53 views

Spatial coordinates (latitude and longitude) are non significant

I want to use latitude and longitude as a feature for models like SVM or Logistic Regression (both for classification). What is the most common approach to use latitude and longitude values as ...
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19 views

Is there a minimum sample size for Besag's transformation of Ripley's K-function?

I am using Besag's L function to test complete spatial randomness for plant populations. Specifically, I am implementing the univariate L-function Lest in R on a ...
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1answer
163 views

Spatial Cross-correlation Function

I have code that calculates a bias-adjusted estimator xi(r) defined as a measure of the excess probability dP, above what is expected for an unclustered random ...
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28 views

Y vs X with spatial variation

I am trying to learn a relationship between two variables Y and X, X is the independent variable. The nature of the relationship is quadratic, from some domain experience, but the relationship itself ...
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14 views

Partitioning Spatial Dependence?

So, I have a group of nations that exhibit global spatial dependence. I want to partition the nations into groups so that, at an intuitive level at least, the "sum of the spatial dependence within ...
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26 views

Determine size of quadrat by point pattern analysis

I'm working with a considerably large spatial point dataset that is irregularly spaced. As I want to average the data based on a particular quadrat size (essentially square grids) I was wondering if ...
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38 views

Goodness of fit for a spatial panel with fixed effects and both spatial lag and spatial error

On a dataset, I performed spatial panel regressions with fixed effects, and with both a spatial lag and a spatial error (both are significant), using package splm in R (Millo and Piras 2012 Journal of ...
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Should I check the z-score if the p-value of Local Moran's I is significant?

The dataset I'm using contains income data per area. The values are not normally distributed as shown in the following diagram. Global Moran's I indicates significant spatial patterns and Local ...
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Conditional Distribution of an Independent Variable for missing data

Let $X=[X_1 X_2 X_3 ... X_p] $be a matrix of p independent variables where $X_i=[x_{i1} ... x_{in}]'$ is a nx1 vector. Let W be a nxn weight matrix based upon queen contiguity (so zero's along the ...
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1answer
35 views

How to determine if there is a spatial dependence in data?

My data consists of data measured at different positions (250 measurements in a 5x5 grid). It has been proposed that results may be somewhat dependent on the position. Looking at the data I don't ...
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1answer
62 views

Residuals plot from ripley K function on spatstat

I am a rookie on R and on spatstat package. I would like some help with the Kres function on spatstat. As is always wise to plot the residuals from any kind of ...
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1answer
47 views

Bayesian models vs Bayesian network models

I'm new to statistical modeling and working on applications in spatial property prediction. Can you help me understand the difference between a hierarchical bayesian model and a bayesian network ...
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80 views

How to deal with underdispersion with binomial data

I'm working with a pretty large dataset (n = 4,500) where 10% of my points (pixels in a GIS landscape) are 1s and the rest are 0s. The full model for my data looks something like this: ...
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26 views

About Hypothesis Test In Spatial Regression

I'm doing estimation of spatial lag/error model using R package "spreg"/"spdep". But I can't find any method to do hypothesis test after regression. For example, I want to test whether two ...
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33 views

Spatial analysis separating size from location in mri

Has anyone seen, done or understand how I can go about analyzing MRI datasets that have been registered to standard (MNI) space. What I´d like to do is analyze the effect on survival of lesion volume ...
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48 views

Spatial cluster analysis

Let's say I have a structure like this : This is a spatial region with measurement of plant population in each site. Black and red represent two regions with different intensities.The question is ...
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22 views

Bayesian Spatial Prediction: What is f?

I'm working my way through Gelfand, A.E. & Li Zhu, B.P.C. (2001). On the change of support problem in spatio-temporal data. Biostatistics, 2:1, 31-45. I'm stuck at: This is absolutely the ...
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1answer
139 views

Plotting a “posterior median surface”

As part of reproducing a model I described partially in this question on Stack Overflow, I want to obtain a plot of a posterior distribution. The (spatial) model describes the selling price of some ...
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76 views

Statistical methods to compare spatial maps

I would like to compare 4 radon flux maps (Bq m-2 s-1) generated using different methods. All of the maps use same projection and have same resolution. I am having trouble finding statistical ...
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0answers
29 views

Find linear subsets in a 2D point (xy) data [duplicate]

My problem is the very idea of how to start the analysis of 2D point patterns, specifically how to find linear trends within their spatial pattern. I have XY data points which are organized like in ...
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48 views

'Extrapolate' a probability density to a different support

here is my scenario: I have N triangles and N probability distributions (of independent variables), and the support of the ith probability distribution is just the ith triangle. The triangles may ...
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1answer
68 views

Principal component (PC) as a substitute for colinear covariates?

I am working on a spatial linear regression and I can tell there is collinearity between covariates. Can I use PCA (Principal Component Analysis) images instead of original covariates to estimate the ...
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1answer
27 views

online resources for spatial analysis [closed]

I am wondering about some good online resources for learning how to implement spatial statistical techniques, like Moran's I and Geary's C, or even K Nearest Neighbors...any help is appreciated. ...