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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0
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1answer
493 views

How to calculate median value of polygon from points in ArcGIS?

I have a point layer coming from LIDAR data containing x,y,z and intensity values. On the other hand I have a layer containing several polygons. All the points are inside the polygons. I need to ...
3
votes
0answers
80 views

Quantifying polyline overlap

I have a set of regions and would like to quantify the degree to which the boundary of these regions are situated on/near rivers. I have turned the regions from polygons to polylines in arcgis 10.1 ...
27
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2answers
3k views

How can I conduct Geographically Weighted Principal Component Analysis using ArcGIS, Python and SPSS/R?

I am after a description/methodology for conducting a Geographically Weighted Principal Components Analysis (GWPCA). I am happy using Python for any portion of this and I imagine SPSS or R being used ...
-1
votes
1answer
401 views

WinBUGs giving 'Illegal memory write error' running under wine [closed]

Ok some I am trying to use Winbugs to do spatial smoothing. I am running r code in R study and using R2WinBUGS to call Wine 1.4 under Mac OSx Mountain Lion. It works ok for some models but for the CAR ...
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0answers
554 views

Validation of Regression Kriging

I am interested in exploring the idea of generating a predictive model for a target variable in a spatial context. I would then like to correct the residuals of this model using kriging, i.e. in a ...
8
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2answers
294 views

How to quantify unevenness of polygon boundaries?

I have two polygons: Polygon 1 and Polygon 2. Using two metrics, area and perimeter length, I want to express quantitatively that Polygon 1 has a more uneven/jagged/irregular perimeter than Polygon ...
7
votes
1answer
252 views

How can I calculate Moran's I in 3D?

This may be a question to post on a GIS forum, but I was wondering if among the spatial data experts here, someone could help me calculate the extension of Moran's I to 3D? Our data is about 3D ...
1
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1answer
108 views

Use of Grass and R w.r.t. Land Use Prediction

In my data mining term project I need to conduct a work on geospatial data related to a big city to show possible urbanization fields in next years. I've used GRASS lately on other projects so I'm a ...
3
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2answers
154 views

How do I visualize a time and space sequence of events in ArcGIS?

I would like to visualize this scenario: I have 5 weather stations. I would like to present a sequence of rainfall events for them. For example, rain was starts at station 2 at 6:09 and then went to ...
0
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0answers
63 views

How to simplify vector lines into an overlaid grid in QGIS?

I'm a relatively new user with GIS software (primarily QGIS) and I'm sure this is probably quite simple but I've been trying to find an answer for ages! I have transportation network data for an area ...
0
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0answers
114 views

Does the Calculation of Spatial Weights Matrix in ArcGIS take into account 3D?

This question is about Spatial Weights Matrix in ArcGIS. Does it take into account 3D or not? I want to calculate Spatial Weights Matrix with SPACE_TIME_WINDOW. Anton
2
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0answers
326 views

About zonal statistic function in ARCGIS

I calculated zonal statistic in Arcgis to get max/min value of each LC types. Broadly, LC image include forest, grassland, waterbody etc. But output max value of zonal statistic function give me 0.972 ...
3
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0answers
93 views

Ways to measure similarities/congruence of tracks (point features) in ArcGIS

I have a sets of GPS coordinates recorded while tracking different cross country runners. What I would like to do is to compare how similar the tracks of the individual runners are. Is there a test ...
1
vote
0answers
22 views

Calculate complete spatial randomness using Python [duplicate]

I currently use the csr() function from Splancs for R (http://cran.r-project.org/web/packages/splancs/splancs.pdf) to calculate complete spatial randomness (CSR) points to be used for spatial ...
1
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0answers
690 views

two results of IDW in ArcMAP are different

i added the following points to ArcMAP using "Add XY Data". x,y,z 7,39,117 27,17,122 27,61,123 46,36,136 52,14,138 55,46,141 56,56,137 65,24,144 65,36,145 Changed raster output size in "options" ...
4
votes
1answer
213 views

How to determine correlation between two databases?

I need to perform some tests and verifications on databases and/or datasets. I need for example to analyze two databases and then determine if there is enough correlation between both. My main issue ...
1
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0answers
165 views

Plotting time-series data in ArcGIS

I'm attempting to produce interpolated plots of water quality time-series data from ArcSDE. This is the data format: OID WELL_ID WELL_NAME SAMPLE_ID SAMPLE_DAT PARAM RESULT ...
9
votes
3answers
1k views

Calculating mean slope: Harmonic or Arithmetic Mean?

I have to calculate the average upslope percent slope for a large dataset, the basic method is detailed here. However, I've begun to wonder if harmonic mean might be more appropriate than the ...
7
votes
1answer
542 views

Comparison of three contour lines

I am looking for a way to spatially quantify the difference between three contour line shapefiles. More specifically, I have two elevation rasters which I intend to create contour lines from, but ...
2
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1answer
608 views

Why won't Tabulate Intersection work?

I can't seem to find much in forums about this - I'm trying to use Tabulate Intersection with two shapefiles. When run in a model, I get a generic error (Error 999999:Error executing function). ...
2
votes
1answer
142 views

Raster export for regressions analysis

I have the following issue: I am trying to do a regression analysis between the (z) values of two rasters. What I would ideally like to have is the raster output not as grid but rather a list of ...
3
votes
1answer
264 views

Calculating Mean Upslope slope, curvature, etc

I'm trying to generate rasters whose values summarize the mean value of a given parameter (slope, curvature, etc.) of the upslope terrain. I feel like this should be doable using only a flow ...
8
votes
1answer
283 views

(How) do the modifiable areal unit problem and modifiable temporal unit problem interact?

I am reconstructing historical time series of land use and other related data from a variety of sources with different spatial and temporal resolutions and would be interested in what possible ...
9
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1answer
496 views

Compare spatial cluster/agglomeration patterns for polygon data

I have agricultural data in form of polygons which I would like to test for spatial clusterings/spatial agglomerations. All in all I have about 40 variables which I can aggregate and standardize in ...
5
votes
1answer
2k views

Creating a subset of points shapefile with minimum distance between points in ArcGIS 10 [duplicate]

I have a sample of ~700 animal locations that I will be using for habitat selection analysis. I am trying to figure out a way to subsample my locations in a way that will maximize my sample size for ...
6
votes
1answer
115 views

What does shading indicate in home range plot?

I've simulated a home range in R using the clusthr function from the adehabitatHR package. The home range is made from 50 x,y coordinates. The output is attached. I'm trying to get clear on what ...
6
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1answer
262 views

how to aggregate the rates, represented by points, within X radius

the point represents rates like 10%, etc. (this was also pretty clear from 2 years ago) -- been trying to do this for 2 yrs... the points dont represent numbers of events since they are rates ...
5
votes
2answers
1k views

How to implement bivariate Ripley's K function in ArcGIS 10?

The attached image shows a forest gap with red pine represented as circles and white pine represented as crosses. I am interested in determining if there is a positive or negative association between ...
-3
votes
1answer
317 views

How to calculate cumulative mean in Arcgis

I'd like to get cumulative mean value from a multiband image (4 bands). How can I do it in Arcgis, ERDAS and ENVI? Thanks in advance
5
votes
3answers
655 views

How to test spatial correlation between two point layers

I have two point layers, which visually have spatial correlation. I'd like to test it but wonder if there is such a method or index?
3
votes
2answers
1k views

What is an appropriate statistic to measure spatial autocorrelation of points with binary values?

I am trying to determine the level of spatial autocorrelation in a point dataset. The attribute I'm interested in is binary (presence/absence of a species), for which Moran's I is not appropriate. ...
4
votes
1answer
725 views

Self organizing maps and spatially Constrained Clustering in R

There are a few algorithms to perform spatial clustering in R but most of them focus on point pattern analysis (for example here). I would like to perform spatial constrained clustering for polygon ...
4
votes
1answer
532 views

How to Reduce Decimal Precision of Image Value in ArcGIS?

I'd like to ask about the value on following image. This is an interpolated precipitation layer using IDW method in Arcgis. On this layer, the values is like this: This is a raster image. After ...
2
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0answers
26 views

How to interprete ArcGIS kernel density units when a population parameter is specified? [duplicate]

Possible Duplicate: How to interpret GRASS v.kernel results? The attached image shows trees in a study area based on their actual height in the field. The trees are overlaying a raster ...
11
votes
5answers
654 views

Learning Spatial Statistics

I have a significant background in statistics, and I'd like to learn more about spatial statistics (and statistics associated with geospatial data). Are there any especially good resources for ...
5
votes
2answers
527 views

Spatial Analysis with Factors/Classifications

When doing analysis on spatial data with associated information that is numeric, it is possible to use techniques such as Kriging or Interpolation or Cluster Analysis to find out interesting ...
1
vote
4answers
4k views

Sum of areas in all each polygon layer?

I've got several layers/feature classes in an ArcMap 10 project. Thanks to everyone's help, I'm able to get the areas for the polygons contained within each layer. By opening the attribute tables ...
1
vote
1answer
155 views

How can I multiply each band of multiband image by separate scalars?

I have an image with 5 bands. I need to multiply each band of this image by different scalars one time (I'm lazy to do it one by one) and then get multiband image as a output. For example ...
5
votes
2answers
715 views

Spatio-temporal block kriging with R package gstat?

In the documentation of sp I saw that the coords argument of the SpatialPolygons function only accepts 2 columns. Is it not possible to create 3-dimensional polygons? I am doing spatio-temporal ...
10
votes
1answer
363 views

How to create an error map to support an average kernel density map?

I've created an average kernel density map by running KDEs on points stacked within the same spatial extent. For example, say we have three point shapefiles representing seedlings in three different ...
2
votes
1answer
213 views

Obtain normalized raster average per polygon?

I have a raster that contains percentages of total forest killed plus a polygon layer that defines different zones. My goal is to find a good statistical representative that describes the forest ...
4
votes
1answer
774 views

How to write values from arcpy statistical output to table?

The attached script is my stalled attempt to perform the following workflow: Create a table and create fields Loop through a folder of point shapefiles and perform average nearest neighbor analysis ...
6
votes
1answer
506 views

Calculating “relative slope” per Mora-Vahrson method in ArcGIS

I'm a longtime lurker who finally decided to register on the forum (in no way driven by my need to have a certain question answered, of course...). I was contacted by a colleague asking for help ...
3
votes
0answers
269 views

How do I access layer attributes from within QGIS' manageR plugin?

This is probably a fairly basic question, but searches for manageR come up with a lot of noise, and there's no manageR tag. What I'd like to do is load the attributes from a particular field of a ...
14
votes
3answers
547 views

How to determine if trees within forest gaps are clustered?

The attached dataset shows approximately 6000 saplings in approximately 50 variable sized forest gaps. I am interested in learning how these saplings are growing within their respective gaps (i.e. ...
9
votes
2answers
2k views

How to get the second nearest neighbor between two point patterns in R?

Is there a way to get the distances for the second nearest neighbor between two point patterns in R? The spatstat package has a function called nncross but it only applies to the nearest neighbors ...
2
votes
0answers
138 views

How are geographic coordinates stored for multivariate statistical analysis? [closed]

In terms of Principal Components Analysis or Multiple Discriminant Analysis, I have used dummy variables to represent a group of like-features that are located in the same geographic region. For ...
11
votes
1answer
396 views

How to associate polygons with the nearest point on a point layer? (Or … how do I assign a postal area to a salesman?)

I have a polygon layer of postal code areas and I want to use them to create sales territories based on where our sales people are based. So I assume that I need to work out for each of the polygons ...
4
votes
2answers
743 views

Spatial query of raster data

I have population distribution data as a raster layer and exposure contours as vector (polygon) layers. What I'd like to do is use the vector layer to estimate the population indicated from the raster ...
1
vote
1answer
241 views

How to fit a polygon to a “best buffer” about a reference geometry in it?

If I have a polygonal geometry gbase, like a street (a rectangular strip), and a reference geometry gref, like a central line of gbase. The question is what is the function (here named BestBuffer) ...