# Questions tagged [autocorrelation]

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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77 views

### Point Similarity Clustering

I am new to geographical statistics so please pardon this question if it is a duplicate. I would like to test if points that are similar are more or less likely to be near each other. I am latitude ...
142 views

### Calculating Moran's I on large point dataframe in R

I have a dataset of about 77,000 points of which I want to test autocorrelation. I have tried to compute the test statistic using the testSpatialAutocorrelation tool in the DHARMa package, which uses "...
30 views

### Spatial autocorrelation coefficients interpretations

I have this result for SDM estimates in R with R2 of 54%. Is the lambda (= -2.04) which is the spatial autocorrelation coefficient a plausible value? I have read in a book that [Elhorst, 2014, P.14], ...
44 views

### What does first requirement for LISA statistic mean?

According to Anselin, a LISA statistic have to satisfy two requirements: The LISA for each observation gives an indicator of the extent of significant spatial clustering of similar values around that ...
29 views

### Measure for spatial autocorrelation in fire occurrence data

I am trying to determine the variables that predict forest fire occurrence in a region in Chile. Firstly, I determined burned areas using LANDSAT data and the dNBR-index. I ultimately made a raster ...
47 views

### Randomly Sample Raster Pixels With a Minimum Distance in QGIS

Is there a way I can sample random raster pixels from a satellite image with QGIS or QGIS plugin? I also need each randomly-chosen pixel to have a pre-defined minimum distance from the other raster ...
63 views

### Reducing “noise” in spatially regressed points

I'm working on spatial data on a grid. I have two variables that I think to be correlated and I would like to build a model (see Fig attached). I did some exploratory analyses following the ...
323 views

### Compute Moran's I on more than one attribute

I am trying to compute global Moran's I to check for spatial autocorrelation among areas of a city. I am using python, in particular geopandas and pysal. My geodataframe looks like: District_name|...
557 views

### 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 ...
254 views

### Error Message when Running Global Morans with Spatial Weights Matrix

I am attempting to run a global Moran's I test with a spatial weights matrix, however when I run the process I always receive an error message and I was hoping someone could point out when I am going ...
68 views

### Geographically Weighted Regression with overlapping polygons

Is it statistically correct (or possible at all) to calculate a spatial regression with (partly) overlapping spatial areas? I have market areas as the spatial unit with different sociodemographic, ...
219 views

### Using Moran's I test for spatial autocorrelation on residuals from logistic mixed model?

I know that tests using Moran's I are not appropriate for binary outcome variables, but can I use that test on the residuals from a logistic mixed model to see if spatial dependence is unaccounted for?...
108 views

### Generate spatial weight matrix from file in ArcGIS

I am trying to create a spatial weight matrix from an existing file in ArcGIS. I need to use another file, as opposed to generate the weights in Arc, because I define non-standard weights. The ...
223 views

### Moran's I: Selecting the best option for conceptualizing the spatial relationship between # births & county locations

I'm using Moran's I to see whether there are clusters of births rates present among the 83 Michigan counties, and, if so, whether the clustering is statistically significant. The inputs are the ...
397 views

### How to check spatial autocorrelation correctly in a glm

I ran a binomial glm as below and from plotting observations i know that there are many observations close to each other and i expect them to be highly correlated. For this matter after selecting the ...
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### Are points similar to nearby points using R?

I am new to spatial statistics. I am trying to determine if points close together are more or less similar. Specifically, I have a series of lat/long points for alligators nests. At some nests, one ...
14k views

### 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 ...
9k views

### Implementing Spatial Autocorrelation using QGIS or PostgreSQL or any other free application?

I am a total newbie on the GIS scene so I hope this is not a stupid question. I have two layers in a PostgreSQL database. The first layer contains points where events happened in Europe. The second ...
230 views

### Autoregressive parameter from autocorrelation using R

I was wondering how to get autoregressive (AR) parameter ("rho") from an autocorrelation plot using R. Below I generated a correlated data and then provided a simple approach to produce an ...
1k views

### Choosing value of Moran's I to say existence of spatial correlation?

I am a GIS beginner. Usually we use Moran's I to evaluate spatial autocorrelation. Everyone knows the Moran's I coefficient ranges from -1 (uniform) to 1 (clustering); I = 0 means no correlation. If ...
398 views

### 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 ...
1k views

### Moran's I on 2D arrays/rasters?

I would like to apply Moran's I spatial auto-correlation measure to 2D arrays or raster files in Python and I am wondering if there is an available implementation for it. I know Pysal offers an ...
1k views

### 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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### Correcting for correlation of kernel density of events to that of their distance from separate feature using ArcGIS Desktop?

I have a kernel density raster of recorded events. These events are correlated to their distance from a linear feature. In other words, density is higher near this line because it is a 'starting point'...
1k views

### Spatial outliers detection in R?

What is the best way to detect spatial outliers in R? With spatial outlier detection I mean: Discover the objects whose non-spatial attribute values are significantly different from the values of ...
249 views

### Testing species distribution model residuals for spatial autocorrelation?

I build a species distribution model with data from location A and tested it on location B. The picture shows a rastermap of location B and what I guess should be the model residuals. Green - are ...
626 views

### Accounting for spatial autocorrelation in rasters

Background: I have a set of fine resolution rasters for the Florida peninsula. These rasters are going to be used in species distribution modeling. Many of these rasters represent variables that are ...
2k views

### 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 ...
661 views

### Why Spatial autocorrelation (Global Moran's I) is producing a p value of 0?

I am undertaking spatial autocorrelation (Global Moran's I) in ArcMap 10.3. The p value returned is 0, does this just mean its extremely significant or is this an incorrect result?
223 views

### 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 ...
787 views

### Test Statistic, p-value interpretation for Local Moran's I [closed]

I am using Local Moran's I in the spdep in R. See this question: https://stackoverflow.com/questions/44104008/spatial-autocorrelation-between-time-series-in-r?noredirect=1#comment75251231_44104008 ...
59 views

### Using spatial regression on interpolated surfaces? [closed]

I have two raster surfaces where I want to test to see If any relationship (A depending on B) can be found and if so if that relationship is statisticaly significant. What are key issues to consider ...
419 views

### Removing spatial autocorrelation (SAC) using Moran's Eigenvectors and predict distribution?

I successfully managed to incorporate moran's eigenvectors as predictor to my species distribution model using GLM (logit). I followed Dormann et al. (2007) and the appendix. I think I got corrected ...
136 views

### How to properly address autocorrelation for logistic regression of spatial data

Background for the Model: https://stats.stackexchange.com/questions/268201/how-to-increase-mcfadden-score-and-choose-proper-predictor-for-binary-logistic-r Data I have: Forest loss points Forest ...
71 views

### Is aggregating points to areal units ever useful - Spatial statistics

I have a large point dataset of a population (By population, I mean that it was not a sample e.g. all houses in a county with an attribute such as size, price, age, etc.). Each point represents each ...
1k views

### 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'...
786 views

### Calculating spatial autocorrelation of raster values?

R is perfectly willing to compute a Moran's I statistic (and probably all of the other autocorrelation metrics) for a raster. As best I can tell, PySal and ArcMap's autocorrelation tools specifically ...
38 views

### Spatial Autocorrelation with a low number input feature

I am an archaeologist using ArcGIS to run spatial statistics/analyses on my data. I want to study the spatial autocorrelation of artifact categories found within house structures across an ...
951 views

### Interpreting semivariogram with high nugget effect?

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, ...
5k views

### Regression Model and Spatial Autocorrelation

I have used OLS and GWR for validating the dependencies between two distinct database. The Residual Square for GWR is 0.82 and thereby making it the right regression model to be used for determining ...
177 views

### Inputs for spatial autocorrelation

I am trying to use the spatial autocorrelation function in the statistical analysis toolbox but I am unsure what I need to set as the inputs. I want to use it to test for autocorrelation in a set of '...
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### OLS tool in ArcMap 10.4: Spatially Autocorrelated Explanatory Variable

I am performing ordinary least squares regression analysis on two variables: K concentration in soil as explanatory variable, and thickness of stalk of plants as the dependent. The K-concentration ...
555 views

### 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 ...
697 views

### 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,...
181 views

### 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 ...
154 views

### 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 ...
42 views

### 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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### 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 ...