# Tagged Questions

A quantitative measure of the linear relationship among values in a dataset and the values (from the same dataset) at nearby locations.

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### Areal Clustering with Differentially Sized Areas

I'm currently learning a little about spatial auto-correlation. I'm quite interested in seeing if areas with higher/lower residuals from a linear regression model tend to be closer to one another (...
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### R-Studio0.99, How to compute correlation between two rasters and serial correlation

I am using R.Studio0.99 version installed on my HP Laptop 4th generation (8GB RAM) windows 8 operating system and I know how to use R studio and some of the library to incorporate spatial data (raster,...
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### Spatial correlograms for binary raster?

I have binary raster data (deforestation hotspot or not) that I would like to plot spatial correlograms for in R, to look at spatial autocorrelation over different spatial lags. I came across this ...
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### Bivariate Moran's I and LISA statistics using two diverse variables at different time

I'd like to use the bivariate Moran's I and LISA statistics using two diverse variables at different time. For example, Population in 1990 and firms' localisation in 2000. Please, I would like to ...
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### How to work with Spatial Autocorrelation (Morans I) on equal weighted point

I have a point feature class. All points are the same, it's not weighted. I want to use Spatial Autocorrelation (Morans I) tool but it only takes a field for weight. I tried fooling it by adding a ...
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### Trouble shooting Incremental Spatial Autocorrelation/Hot Spot Analysis

I'm trying to do a spatial analysis of rural school closings in Brazil (ultimate objective to do OLS/GWR). I have census data from 2005 and 2014, from which I've calculated the relative percentage of ...
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### What is the difference between spatial regimes and spatial heterogeneity?

Let me cite excerpts from the GeoDA-Gloassary (https://geodacenter.asu.edu/node/390) Spatial regimes: Spatial regimes are a form of spatial heterogeneity, which implies structural differences ...
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### Interpreting variogram: negative values beyond model sill?

The negative values mean that there is negative autocorrelation at some far distance, like a repulsion. How would this affect assessment of the range? (This is just for learning the scale of a ...
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### Why are spatial lagged exogeneous variables rarely used?

In the publication "Regional Productivity and Income Convergence in the Unified Germany 1992-2000" (link) it is claimed without detailed explanation: "Usually, in spatial econometric models only ...
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### What are the practical differences between Moran's I and Geary's C

What are the practical differences between Moran's I and Geary's C for gridded datasets (e.g. temperature) on a continental scale such as USA? Which is more applicable?
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### How to choose the correct range for Moran's I correlogram with irregularly shaped areas? [duplicate]

This question was first ask on Cross Validated, but I think it might be better suited to Geographic Information Systems. First question here, so I apologize if it doesn't fit! I am doing correlograms ...
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### Choosing the range of the correlogram with an irregularly shaped area

I am doing correlograms (Moran's I) between 125 plots. Those plots are located in large patches in my study area (see figure). The entire study area is approximately 2000 x 2000 m. I know that the ...
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### Comparing different degrees of local spatial association

I have two data sets and want to compare/evaluate their degree of spatial association expressed in terms of the LISA statistic. The local Moran's I statistic gives for each point a (pseudo) p-Value ...
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### Algorithm for spatial clustering?

I have a series of 2D maps with values ranging 0.0 to 1.0 spread all over. The algorithm that produces them is an application of the fractional Brownian motion. Each map measures 101x101 pixels or ...
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### How to calculate Spatial Autocorrelation of grouped points in ArcMap 10.2.2

I have 32 points uniformly distributed with 7 attributes that comprises continuous values. I used the Grouping Analysis tool in ArcMap 10.2.2. I set 2 groups that have clear differences and are also ...
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### Interpreting semivariogram high nugget

I made a semivariogram in R using package gstat, variogram() function. I want to see if there is spatial autocorrelation in the residuals of my model (species abundance as a function of habitat, ...
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### Variogram to assess spatial auto-correlation in grouped surveys in R

I have a large dataset with coordinates of survey locations, and results for presence or absence of a species. These surveys are spatially clustered, with four in a line separated by 1km each, and the ...
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### Interpreting Global Moran's I and should I krig?

I am trying to weigh up if kriging (or cokriging) the residual error from my model is a valid approach. My first step was to compute whether the error is spatially autocorrelated. I have done this ...
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### How to create an autocovariate in ArcGIS for use in autologistic regression model

I am trying to create an autocovariate variable for use in an autologistic regression. I have a GIS point Shapefile of the response variable, in binary form for presence/absence of a plant species. ...
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### Moran's I correlogram: advices on interpretation

I was interested in assessing to what extent the occurrence of a given land characteristics is influenced by autocorrelation. I have a point shape file, and for each point the presence/absence of that ...
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### spatial autocorrelation and calculation of autocovariate term

I was reading some literature on spatial modeling, where it is stressed that in using regression (e.g., the Generalized Linear Model family, comprising Logistic Regression for example) the possible ...
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### Conflicting results for spatial autocorrelation tests

I am working with an imbalanced (5%/95%) presence/absence dataset. I've created 25x25 m. raster cells that are categorized '1' or '0'. My Geary's C result (~0.993) and Moran's I result (~0.0045) are ...
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### A way to measure whether two variables have similar spatial distributions?

I'm doing a project that's looking at a certain disease outbreak and vaccination in California counties using arcmap. I have aggregated data joins for disease outbreak rate, personal belief exemptions,...
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### Spatial autocorrelation analysis (Global Moran`s I) suspicious z-score

I have a doubt concerning the Spatial autocorrelation analysis Global Moran's I, in ArcGIS 10.2. I did the analysis with 3.372 features of a defined study area, and it showed that the features are ...
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### Spatial correlation

I want to do spatial correlation with many variables. In fact when I do correlation densities points results are better than when I work with attributive data. Can I use the result of the density of ...
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### Calculating Autocorrelation in Different Zones

I'm an intermediate-ish user of ArcGIS 10.2 (win7 pro, hardware robust enough to handle very large datasets and computationally intensive analysis) with perhaps a simple problem that's evading me ...
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### ArcGIS implementation of an R-script for estimating spatial autocorrelation

How do I implement the following in ArcGIS? rho.from.data <- function(ras){ require(spdep) require(maptools) #-- Generate Spatial Pixels data frame from raster file --# r2r <- as(ras, "...
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### Using Ripley's K Function in ArcGIS for coral density along a transect?

I have some data from transects taken in a mangrove system. I want to analyze the spatial distribution /some sort of spatial statistics of how clumped/dispersed corals are along this linear transect. ...
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### Getting incorrect results for Geary's Coefficient algorithm (incorrect math?)

I'm not sure if anyone here can help me with this, but I'm currently working on a program that uses a spatial autocorrelation algorithm to analyze patterns in an image. It's supposed to return values ...
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### Unexpected Moran's I value in R using a chessboard example

I'm running into unexpected values for Moran's I when using the Moran.I function in the R library "ape". My understanding is that a chessboard is an example of perfect negative spatial ...
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### Variogram model fit compatability among geoR, gstat, and nlme packages in R

I'm trying to specify the covariance structure parameters in a linear mixed model (using the correlation structure facilities in nlme). The parameters are estimated from a gstat or geoR variogram ...
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### Classical or robust variogram for incorporation into generalized linear model

I'm modeling counts of organisms over time at eleven locations. I'd like to account for temporal autocorrelation in the counts, assuming it's present. As the data are not equally spaced in time, I'...
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### Geary's index of spatial autocorrelation

Does anyone knows If there is a way to calculate Geary's index of spatial autocorrelation on open source gis?
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### Can I ignore very low levels of spatial autocorrelation in my data?

I have >1 million postcodes clustered in ~7000 middle super output areas for England and Wales which I'm analysing using MLwiN. I have used a multilevel model with random effects and have clustered ...
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### Interpreting Moran's I results

I have a sample of data taken from regions of a country! i want to test if there are any spatial autocorrelation on my data using Moran Indice test. the null hypothesis: is that there is no spatial ...
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### Specifying Bayesian Spatially lagged dependent (SAR) variable regression in winBUGS or Stan

I have been looking for code example on how to specify a SAR spatially lagged dependent variable regression in winBUGS (geoBUGS) or, if possible, in Stan. I mean, something of the format: Y = beta_0 ...
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### Lagrange Multiplier in lm.LMtests (spdep package for R)

Are the Lagrange values comparable in lm.LMtests? If both RLMerr and RLMlag are significant, would the test with the largest Lagrange value be considered 'better' at explaining the spatial ...
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### Getis-Ord GI and Moran's I when interested in clustering of data values not points

I have a dataset with many clustered (often coincident) points, each of which contains data. I am not interested in the fact that the points are obviously clustered. I would like to know whether the ...
413 views

### How do I generate a correlogram from a GeoTiff using R?

I'm trying to evaluate the scale of spatial autocorrelation for a bunch of rasters I have as GeoTIFFs. I'd like to be able to do this entirely using R, in order to maintain smooth workflow. What's ...
2k views

### R raster Package Moran's I interpretation

I am using raster package to calculate the local Moran's I . The example gives the range of Moran's I between - 1 to 2.47. On my own data I have see the value range -3.070423 - 7.228558 How can Moran'...
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### R - What is the purpose of .GAL lattice file?

Could someone please explain to me what the purpose of a .GAL lattice file is? I want to see if my data are spatially autocorrelated and I've been following Bivand (2013). I have loaded my polygon ...
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### How do I randomly alter a raster with som correlation

I need to randomly alter an existing raster. The original raster is essentially a topography map that measures its values around a normal distribution ranging between 0.5 and 1.5 The new raster ...
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### Contradictories results with Moran's I and Geary's C

I have contradictories results for both index. One side Moran's I says there is a positive correlation , but Geary's C says there isn't any correlation. Geary's C is more sensitive local ...
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### Help interpreting Moran's I and Geary's C results

I've got some doubts about how to interpret some results for a work. And I) would like someone could confirm or improve my conclussions. I made a correlation analysis with SEXTANTE software in gvSIG. ...
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### Autocorrelation: Best way to assess mixed uses and building scales?

I am trying to find the best way to measure the spatial distribution and scale of "mixed-uses". i.e. the mix of different building use categories such as residential, commercial, industrial, etc. I am ...
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### Finding closest anticorrelated polygon or automate what is learned in semivariogram?

I am trying to do spatial autocorrelation of sorts based on a layer of polygons of mean rainfall data. I want to see how rainfall deviates from a certain point on the landscape. Essentially, I want to ...
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### Determining spatial cluster of park types in ArcGIS

Question 1: I am trying to determine which (if any) of my different park types are spatially clustered across my study area (city boundary). There are 162 total parks, 9 nominal categories (which ...
535 views

### Problems with spatial autocorrelation in Geographically Weighted Regression (GWR) analysis

I have conducted an Ordinary Least Squares (OLS) and Geographically Weighted Regression (GWR) analysis in ArcGIS where I have tried to predict biodiversity patterns in an area. When I examine the ...