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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143 views

Spatial Lag & Error Regression Models for Negative Binomial or Poisson?

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
30 views

How to aggregate values of different statistical areas that are overlapping?

Let's say I have one polygon layer counties with the polygons of administrative borders and another layer postal codes with the polygons of postal code areas. I have some statistical values per ...
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3answers
79 views

Spatial distribution of an invasive specie across a landscape : what analysis?

I'm studying the spatial distribution of an invasive specie introduced in a natural area. This plant, that thrives in sunlight, grows in thickets (patches). The population of my study site (10x10 km) ...
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30 views

Comparing point pattern distributions using Geostatistics with R?

I have a data set consisting of about 1,500 points of an unknown distribution. About 60 of the points represent special conditions like infekted people. How can I determine if the 1,500 points and ...
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3answers
787 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 ...
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3answers
2k views

Determining statistical relationships between rasters using R vs ArcGIS Desktop?

I am trying to analyze how sets of rasters relate to each other using some statistical techniques. As, I don't have much experience using the spatial statistics tools in ArcGIS I was exporting my ...
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1answer
36 views

Choosing R package for discrete choice model?

I am at a loss as to which R package and approach to use for my modeling. The background is: I have a transportation survey dataset combined with many other GIS datasets. I am attempting to ...
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3answers
84 views

Best Projection for Getis Ord Gi* Statistic Analysis

I am about to calculate the Getis Ord Gi* statistic for some rasters whose extents are global. In choosing a projection, do I want to preserve distance (e.g. equidistant) to obtain accurate ...
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45 views

Drawing boundaries between discrete features based on attribute values in ArcGIS for Desktop?

There is a point feature class with a certain numeric attribute (let us say, populated places with population). I wonder if there is, in ArcGIS, a way to draw polygons such that the sum of the ...
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0answers
37 views

Grouping Analysis (Clustering) of polygons with streets as borders in ArcGIS?

I have a question about the Grouping Analysis Tool in ArcGIS. Is it possible to use streets as spatial borders for the groups? I want to group a city district autmatically with multiple attributes, ...
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2answers
47 views

Which training courses in geostatistics can you recommend?

I'm looking for excellent geostatistics courses all over the world, including online courses. In particular, I would like to learn more about the kriging method. Can anyone give me some suggestions?
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6 views

Where can I find spatial data on Enumeration Area boundaries from the South Africa 2001 Census?

I am trying to locate spatial data for the boundaries of South African Enumeration Areas (EAs) from the 2001 Census. The links to the data from the 2001 census on the Statistics South Africa website ...
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22 views

Heat Map with species distribution [closed]

what I am trying to do is to generate a heat map depicting the spatial distribution of certain species found in a lake, in association with their sex. For example, species_a+male or species_b+female ...
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1answer
46 views

How can I create a valid probability map of species distributions based on presence/absence data from multiple quadrats?

I am somewhat new to GIS and only beginning to learn spatial statistics/analysis. I am an ecology grad student doing a before and after study on invasive plants and their responses to management ...
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1answer
36 views

What is a “value raster”?

I want to understand the concept of a "value raster" and if I can use it in neighbourhood statistics.
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1answer
999 views

Why are Low Values showing as hot spots?

Im running hotspot analysis on point data, attempting to examine pollution emissions. I ran spatial autocorrelation first in order to determine the default distance threshold to use in the fixed ...
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2answers
169 views

PostGIS: ST_Equals false when ST_Intersection=100% of geometry?

I have 2 datasets consisting of cadastral parcel data - roughly 125,000 rows each. The geometry column is WKB polygons representing parcel boundaries; all data are geometrically valid (the polygons ...
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0answers
19 views

Verifying time-invariance for spatial gradients of air pollution?

I have data from a network of NO2 passive samplers. Measurement are repeated in the same positions in different years. I need to verify if spatial gradients in air pollution remain constant in time, ...
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9answers
12k views

Open source methods for kriging?

I have a point dataset which I'd like to Krige, ideally using an open-source software package. If possible, I'd also like to choose the semi-variogram model during the process to improve the ...
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1answer
244 views

Interpolating points observed with different time duration

I am doing spatial interpolation with a group of points. Some points have complete observation of events: for a period of 24 hours we have observed N events in each point. These points have N ...
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1answer
165 views

Interpolating lots of points with seemingly good spatial density

I'm using Arcmap 10 and I have scattered points (denser in an area). Each point represents a thickness value of a simulated avalanche deposit. I want to get a raster from this points which I will ...
5
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1answer
128 views

Kriging to calculate forest biomass?

I am trying to create biomass map using Kriging from ground sample point. I have about 150 and 53 point plot for dense and sparse strata. The data is not normal so I have transformed it. After ...
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0answers
56 views

Kriging metal concentration with irregular set of sample points

I need to perform some interpolation to map a metal concentration around a platform. The distribution of my stations is not regular (see figure below where stations are the green points labelled with ...
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5answers
8k views

How to cluster spatial data in R?

I am very new to R, so please bear with me : > I have bunch of data points with latitude and longitude. I want to use R to cluster them based on their distance. I have already taken a look at this ...
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2answers
46 views

Low point density analysis

I'm working on a project for a conservation plan. Part of the plan requires that areas added for conservation have less than one structure per five acres (these are pretty large, mostly undeveloped ...
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2answers
1k views

how to do change detection in ERDAS

I'd like to ask a really simple question. I want to obtain the size of unchanged, decreased, and increased area etc (just like shown in image below) from 2 classification images in 2000 and 2007. How ...
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2answers
28 views

Arcgis 10-Sample selection

I am using arcgis 10 and I would like to select (in a manner of well spatially distributed) some of the polygons included in a .shp as testing population for a statistical analysis. The rest of the ...
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0answers
45 views

Optimal distance and power exponent in IDW

I want to apply IDW interpolation for my region of interest, and through leave-one-out cross validation I want to find the optimal values for the distance parameter and the power exponent. I know that ...
2
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1answer
68 views

Sublayers or Multiple Visualizations for CartoDB

I'm trying to learn a bit of CartoDB by creating a heatmap using crime data available on the city's website where the raw number of crimes are displayed for each police district. So far I've been ...
29
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7answers
11k 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 ...
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0answers
19 views

Problem with ST_SummaryStats, ST_Buffer, and casting between geometry/geography types

I have a test raster that covers the world ((-180 90), (180 -90)). The SRID is WGS 84 (EPSG:4326). Values for cells in the north-western quadrant ((-180 90), (0 0)) are random integers in the range 1 ...
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1answer
66 views

Mean Center/Median Center tool providing points mathematically centered but physically appearing in the wrong location

To create population weights, I'm using the Mean and Median Center tool to find the center of our populations in census tracts. However, I've noticed that some of the points that are popping up are ...
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0answers
61 views

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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1answer
71 views

resize map and add points to it using R

I am working with spatial data UK. The map is plotted here. I want to resize the map and make it bigger and clear! here is my code LA <- readOGR(dsn =".", "infuse_dist_lyr_2011_clipped") ...
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0answers
17 views

scenarios to make multiple data maps comparisons?

I'm using Leaflet (and several of its plugins) to make a custom SOLAP solution and i want to offer to the user, the possibility to make data analysis and comparison between multiple maps, my question: ...
4
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3answers
237 views

How to find buffer radius around raster cell that covers a defined sum of raster cells?

I want to do a neigbourhood analysis on some raster data. I need to know how big a circle around each raster cell must be to include a certain amount of specified raster cells. Let's say that for ...
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1answer
490 views

how to choose stratified random sample on multispectral image

I'd like to choose random samples from multispectral image according to each Land Cover image. The multiband image has 70 bands representing land surface temperature data from MODIS. Land cover image ...
2
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1answer
1k views

Outputting results message from spatial statistics tool to text file using Python?

I'm using the following tool in ArcGIS 10 - Calculate Distance Band from Neighbor Count (Spatial Statistics). I'm using a python script to execute this tool several times on different shapefiles: ...
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3answers
148 views

Summarize the total area of land use polygons within map sheets - how?

I would imagine that at least some of you have encountered similar problems to mine and I´d like to hear how you solved them. I have a map sheet index (a grid as a shape file) covering a large area. ...
3
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1answer
143 views

Dissolve Polygons using R / join specific polygons

I have data in shapefile format :: UK_boundaries I am new to R and Spatial data as well, I am trying to join some areas to be as one area no line(s) between them. Based on my search I understand ...
5
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1answer
1k 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) ...
5
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1answer
108 views

Creating forest patches from land cover layer?

I have a land cover layer from which I've extracted the tree canopy class and set all values that are not tree to NULL. I've also converted it to a vector and exploded it to make single part features. ...
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3answers
51 views

Selecting Features and Averaging Attributes

I currently have two point shapefiles, SHP A with approximately 75 points and SHP B with approximately 2000 points. What I would like to do is: 1) For each point in SHP A I would like to find the ...
2
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1answer
435 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 ...
2
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1answer
115 views

Incomplete intersection area using gIntersection in R

I have two SpatialPolygonsDataFrame, one of them is the deforested area in the Amazon and the other is the city of Vila Rica, which is in the same region. I would like to calculate the total ...
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1answer
70 views

Testing correlation between two polygon features

I am working on a project looking at county boundaries for the state of California. I have 2 polygon datasets with this same geographic boundary, and these datasets, when mapped individually, visually ...
4
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1answer
3k views

Joining polygons in R

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 ...
4
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1answer
675 views

How to split a polygon using R

I have an irregular polygon which is a spatial object. I want to divide it into multiple polygons (say, n=25) with equal height. To show how I want to divide it, I've plotted grids on the ...
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1answer
90 views

mathematics of spatial diffusion models

There are different types of spatial diffusion such as contagious model, migration model, etc. What are the good books to learn about the mathematics behind these spatial diffusion models?
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1answer
68 views

Kernel density estimation across multiple UTM zones

I'm trying to compare the spatial distribution between two groups of fishing locations (for each of several different years) in the Bering Sea (lat's ~53 to 65N, long's ~ -178 to -158W. My preliminary ...