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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20 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, ...
7
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1answer
277 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
233 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
201 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
78 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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2answers
90 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
2k 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
43 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
112 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 ...
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1answer
253 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 ...
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0answers
85 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
397 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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89 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
196 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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3answers
354 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
879 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
2k 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
549 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. ...
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1answer
685 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 ...
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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) ...
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3answers
85 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
577 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
360 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
1k 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
103 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?
2
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1answer
127 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 ...
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2answers
109 views

ArcGIS compute nearest network neighbour for each point

I have a set of points and I would like to calculate a value for each point to indicate how 'clustered' to other points that point is. Distance to nearest neighbour (through a network) would do fine. ...
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1answer
1k views

Trouble with Hot Spot Analysis (Getis-Ord Gi*) tool in ArcGIS

I am trying to locate areas with a high rate of accidents involving bicyclists or pedestrians per car accident of any kind. I have a point file of accidents and a point file of all those with ...
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0answers
19 views

implement aspect in least cost path analysis to account for downhill and neutral ground movement [duplicate]

I am creating a least cost path model for large species that migrate over large distances across a rugged landscape (elk, deer, etc.) To calculate movement cost I am using a slope raster but I ...
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2answers
436 views

Test for spatial randomness with Ripley's K or L function in R

I have a spatial point pattern that I would like to test against complete spatial randomness. I managed to plot a Ripley's K function for my data and a function for a random distribution with a ...
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4answers
32k views

How to convert zip codes to latitude and longitude?

I have a data set that includes a list of zip codes. Is there a way in R to convert these zip codes to latitude and longitude coordinates?
2
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1answer
517 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 ...
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0answers
170 views

Search Radius for Line Density [closed]

I have been working with GIS for many years but I am fairly new to the spatial analyst side of things. I am working with many satellite tracks for many different individual animals and would like to ...
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0answers
139 views

Extract mean value of a raster into a grid shape file [closed]

Hello guys I need your help I have a soil map of an island and a Grid polygon. I want to extract the mean value of the soil map to polygons squares of grid. I read this and this but Ι can't find the ...
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2answers
96 views

spatial relation between springs (points) and geological faults (polylines)

In ArcGis 10.1 (advanced license), I have digitized the geological faults (polylines) and the location of water springs (points). Since, relying on literature, there is a potential connection between ...
3
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0answers
271 views

How to deal with data which are not normally distributed when kriging?

I'm a novice with advanced spatial interpolation, and I'm trying to use the Geostatistical Analyst to interpolate a surface based on borehole data, using Ordinary Kriging. The help file explains how ...
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2answers
3k views

Is there a Free Aggregate Points tool out there for ArcGIS 10?

I need to do some Getis-Ord analysis but first I need to aggregate my points. I know of XToolsPro, but the aggregate points function is locked and you must purchase a license to use it. I am ...
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1answer
51 views

How to Predict demand on a bus route, considering variaton in kms and price?

If there is a route (line) modification, I mean change on distance; and also a change on the price for the user. How can I calculate the demand on the next year, considering seasonnality. What would ...
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0answers
32 views

Metrics of change between vector datasets

I have an old and a new set of parcel data which I'm looking to compare. I'm looking to compare changes in individual parcel geometries, so boundary/corner adjustment. Currently each parcel we have ...
5
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0answers
53 views

Clusters of Same Size? [duplicate]

I am attempting to use the Grouping Analysis tool in the Spatial Statistics (in ArcGIS 10.2) to group state high schools (points) together based on enrollment and location. Is there a way to make ...
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0answers
106 views

ArcGIS 10: How to mask a raster by using extract by mask tool If the feature mask is larger than the raster area?

I have a problem to mask the the raster which has values ranges -0.73106217384338 - 0.94593381881714. These values have been derived by using equatin (B3-B4)/(B3+B4) from Landsat band 3 and band 4 ...
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2answers
46 views

How to see whether a set of postcodes have a typical distribution to the whole postcode population of UK?

For my dissertation I have a dataset of postcodes of 9984 that I am converting to coordinates atm. I looking to find whether this dataset has a 'typical or 'atypical' spatial distribution compared ...
2
votes
2answers
240 views

Calculating quantile values over a stack of images with grass gis. Help needed on r.series

I need to calculate the values for the 25%, 50%, 75% and 90% quantile over a series of rasters (time series of ndvi values from landsat). I am exploring the r.series command in Grass GIS, but the ...
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0answers
27 views

Trying to produce a map of Household behavior with identified explanatory variables held constant/equal

I have a map of the dependent variable, median household vehicle travel, and independent household characteristic variables, median income, mean household size and median age, aggregated to census ...
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2answers
227 views

Statistical Analysis using ArcGIS

I have points containing data on temperature from 1951-2000. All data have X,Y coordinates. I have raster files in the same period. Two data sets have different data processing hence different values ...
0
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3answers
721 views

Capabilities of the Analytical Hierarchy Process (AHP) in conjunction with the weighted overlay tool

I am making a prospective map of fossil deposits using the "Weighted Overlay" ArcGIS tool. Input factor rasters are mostly topographic in nature (elevation, roughness, TPI, etc). Initially, I had ...
2
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1answer
151 views

What are the geometric principles and GIS techniques that I can use to generate a postcode coverage of my city at street scales?

Postal codes of Brazil and another countries are oriented to distribution logistics, and improvement of reliability in writing the postal addresses; but without much concern for the spatial ...
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1answer
357 views

Problem in creating neighbors, area and perimeter in spatial econometrics using R

I’m working on a spatial cross section model with R-programming-language. I’m running these codes which refers to anselin data (spatial_columbus) in spdep package. I found them from these links: ...
2
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0answers
147 views

Spatial Autocorrelation tool vs. Incremental Spatial Autocorrelation

When you run the Spatial Autocorrelation (Monrans I) tool, you have the option of setting 'Conceptualization of Spatial Relationships'. This option isn't available for the Incremental Spatial ...
8
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2answers
3k views

How to Find the Average Raster Value of an area defined by a shapefile using R?

I have a set of raster images which represent a specific month over the years, and I want to make a timeline of the average values of an area using a shapefile. How do I extract the values from the ...