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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4
votes
1answer
75 views

How to choose a GRASS kernel density function?

I'm starting to use the Grass module on QGIS, and I want to do a heatmap, so, I'm creating a new surface using the kernel function. But, GRASS come with 7 types of kernel functions, how do I know ...
1
vote
4answers
236 views

Detection of geographical trend of a variable

What is the best method to detect and graphically display the spatial trend of a variable? I'm looking for something that tells me the probability that the trend is from "north-west to south-east" or ...
2
votes
1answer
2k views

joining polygons

I am wondering how to join spatial polygons using R code ? I'm working with census data where certain areas change over time and I wish to join the polygons and the corresponding data and simply ...
1
vote
0answers
469 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 ...
4
votes
0answers
91 views

Estimation of values for unsampled points

I want to measure biomass on a coastal mudflat. I can only access points inside the polygon. Are there any methods available that would allow me to estimate values of the points outside of the ...
1
vote
1answer
105 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 ...
7
votes
2answers
246 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
229 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 ...
2
votes
0answers
30 views

How does changing the kernel density search radius affect the units expressed in the map legend? [duplicate]

I'm trying to understand how ArcGIS 10.1 handles kernel density values and how these values are reported in the legend. For example, the following parameters were used for the KDEs in the attached ...
0
votes
0answers
62 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 ...
8
votes
2answers
193 views

spatial and spatiotemporal analyses

I have a dataset that consists of 247 mosquito traps placed in fixed positions and sampled weekly for 23 weeks. I also have dengue disease incidence data (indexed to home address) during the same time ...
1
vote
2answers
688 views

What to do when raster cell size is larger than zonal vector feature in order to collect statistics?

I am trying to extract the mean cell values for a raster dataset based on a survey grid polygon feature using ArcINFO 10.1. The cell size of the raster dataset is about 4 times the size of the survey ...
3
votes
0answers
80 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 ...
2
votes
1answer
325 views

How to interpolate GPS data correctly?

I'm working on a project that involves using linear interpolation to fit lines to lat/lng points. I'm pretty new at scientific programming related stuff, and I was wondering if people could steer me ...
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 ...
6
votes
2answers
333 views

What do ArcGIS regression analysis warnings 000853, 000916 & 000981 mean?

I'm trying to do regression analysis using a shapefile which contains dependent variable (NDVI) and explanatory variable (prec) in ArcGIS. First, I run GWR analysis and then run spatial ...
2
votes
1answer
397 views

How to assign value to field of layer based on spatial query with another layer?

I want to assign a value to a field of a polygon layer based on the value of a field on another polygon layer, using a spatial query. My first polygon layer contains buildings and the second contains ...
6
votes
1answer
196 views

Assigning costs to a road network : use raster or vector?

I have a road network in a PostGis database (db_routing). In another database (db_environment), I have some spatial features of the surrounding environment (trees as points and water bodies as ...
4
votes
1answer
190 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
vote
0answers
156 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 ...
7
votes
1answer
447 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
votes
1answer
521 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
133 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 ...
9
votes
3answers
970 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 ...
8
votes
1answer
257 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 ...
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 ...
3
votes
0answers
142 views

How does Zonal statistics handle pixels that are on the border of the polygon?

I am using the plugin zonal statistics to calculate the sum of the raster cells within polygons. How does this plugin handle pixels that are on the border of the polygon, are those cell values ...
6
votes
1answer
112 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 ...
4
votes
1answer
795 views

Interpolating Maps - Statistical Learning Techniques vs Spatial Statistics Techniques

I have recently begun experimenting with the interpolation of variales over a whole country. I have good sized training set where I have several dependant variables (continuous and categorical) ...
9
votes
1answer
424 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 ...
6
votes
1answer
250 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 ...
3
votes
2answers
151 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 ...
5
votes
3answers
569 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´╝č
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
647 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 ...
2
votes
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
515 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 ...
2
votes
1answer
306 views

Accounting for Spatial Autocorrelation in ZINB Model?

I'm doing an analysis on disease in Chile. I'm using the rate as the Dependent Variable and both remote sensing and housing-type data as the Independent Variables. I have several questions regarding ...
5
votes
2answers
443 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 ...
-3
votes
1answer
285 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
2
votes
0answers
299 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 ...
1
vote
1answer
143 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 ...
4
votes
1answer
453 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 ...
10
votes
1answer
332 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 ...
23
votes
6answers
7k views

Tutorials to handle spatial data in R

Does anyone know some good tutorials to handle spatial data in R? I know that there are some packages like rgdal and maptools but I haven't actually found usefull tutorials to get in touch with the ...
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 ...
4
votes
1answer
659 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
457 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 ...
0
votes
0answers
102 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
5
votes
2answers
682 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 ...