Partitioning data points into subsets of objects according to their mutual "similarity," without using preexisting knowledge such as class labels.

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40
votes
3answers
10k views

Spatial clustering with PostGIS

I'm looking for spatial clustering algorithm for using it within PostGIS-enabled database for point features. I'm going to write plpgsql function that takes distance between points within the same ...
22
votes
5answers
4k views

How to identify clusters in vector point data?

I have a vector dataset of rural broadband data-points (how fast, etc.) and I'd like to explore if there are clusters of points with similar characteristics, and to plot polygons encompassing them. ...
22
votes
6answers
913 views

What tools for regionalization/redistricting can you recommend?

I am looking for tools for regionalization / districting in GIS. So far I have been able to identify Districting ArcGIS extension (now also online) REDCAP (currently limited to 50k input polygons) ...
18
votes
4answers
2k views

How to create a polyline-based “heatmap” from GPS tracks?

This winter I am planning to track my downhill skiing/snowboarding using a GPS. Most of my riding will occur at the same resort. I would like to be able to create a sort of "heatmap" that shows the ...
14
votes
8answers
10k views

How to Create Animated Cluster Markers in OpenLayers/Leaflet?

I want to use Leaflet due to the smooth transitions which Openlayers seems like they can't match. I specifically require the ability to cluster markers with custom styled marker groups. The best ...
14
votes
3answers
463 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. ...
13
votes
3answers
1k views

Best practices for visualising clustered features in web maps?

I'm looking for the best symbol to display clustered features in the ArcGIS Server JS API. I don't like the "fly-out" animated cluster symbol, as used in the Silverlight API clustering or the JS ...
13
votes
4answers
5k 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 ...
12
votes
4answers
4k views

Clustering Trajectories (GPS data of (x,y) points) and Mining the data

I've got 2 questions on analyzing a GPS dataset. 1) Extracting trajectories I have a huge database of recorded GPS coordinates of the form (latitude, longitude, date-time). According to date-time ...
11
votes
4answers
1k views

How can I generate irregular grid containing minimum n points?

Given a large (~ 1 million) sample of unevenly distributed points - is it possible to generate irregular grid (in size, but could also be irregular in shape if that is possible?) that will contain ...
11
votes
1answer
271 views

Spatial analysis and clustering near features

Im working on marking behaviour in group living animals and im interested in how marking behaviour is affected by certain characteristics of the neighbouring groups. I have plotted the territories of ...
11
votes
1answer
316 views

How do I create groups of points from lat/long pairs?

I have a database which contains Lat/Long pairs to identify the location of points of interest. I would like to group the points of interest into groups of 10. The group should be geographically ...
10
votes
1answer
172 views

Stratified OpenLayers Clustering

I have an OpenLayers map with point clustering, but I want to apply a much finer granularity to the data represented in the map. Specifically, I want to stratify the clusters according to an ...
9
votes
4answers
4k views

How to find Clusters of N Points Within X Distance?

We have tried two methods of cluster analysis: Cluster and Outlier Hot Spot ... but neither meets our specification which has these 3 parameters: a Set of Point features N points within a ...
9
votes
1answer
107 views

Natural neighborhoods terminology

Sometimes the hardest part of an analysis is knowing what something is called. What are some R packages, but more importantly, terminology I should be searching for to define contiguous city ...
9
votes
1answer
355 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 ...
8
votes
2answers
526 views

How do I group near points with GPS positions?

I'm an IT person so I don't know too much about projections and so on, I hope you can help me. I have made an application for Android that collects a GPS position, so I have the latitude and the ...
8
votes
1answer
4k views

Using Drop Markers and MarkerClusterer together?

I want to create a rather visually appealing representation of time-series data (Costco Store Locations w/ opening dates). My idea was to plot them on a map, in time-series, but it seems that the ...
8
votes
2answers
4k views

How to cluster Google Maps kml overlay

I have several thousand markers stored in a kmz file that I load into a Google Maps (v3 API). I've looked around to find a way to cluster the overlay data, but to no avail. MarkerClusterer looks ...
8
votes
2answers
2k views

Incremental spatial clustering algorithm

I'm in search of a incremental spatial clustering algorithm. Here is my use case: users create entries with an initial position users may change the positions of existing entries I now want to ...
7
votes
5answers
2k views

Algorithm to find polygons enclosing points

I'm trying to find an algorithm that can determine the smallest possible polygons to cover a number of points. I know how to get the convex hull around all the points, but say that the points are ...
7
votes
6answers
5k views

How do I cluster XY point data? (ArcGIS 9.3)

I have a whole bunch of icons displaying on a map, I want these clustered together as was suggested to me for a different question here... ArcGIS 9.3. How do I increase Picture Marker Symbol ...
7
votes
3answers
949 views

How to cluster points based on a kernel density?

I have a large dataset with 36k points representing commercial land uses, each with a field containing the square footage. I have run a kernel density analysis on this dataset, producing a raster ...
7
votes
2answers
2k views

Spatial statistics tools : clustering analysis on raster data

I've an apparently simple problem, but i can't find a clear methodology to use. I'm tasked to delimit "urban areas" by vector convex polygons, using the Gridded Population of the World dataset from ...
7
votes
3answers
415 views

How do I figure out if there are clusters of one set of points around another set of points from a different layer?

I want to see if there is clustering of a certain type of buildings (x) around another type of buildings (y). The two point files are in different layers. I cannot figure out which tool I would use to ...
7
votes
1answer
611 views

Appropriate distance metric for spatial clustering of geographic coordinates

I have a set of locations in geographic coordinates, and I would like to group the points using hierarchical clustering followed by tree-cutting at various "heights" in order to calculate group-wise ...
7
votes
1answer
179 views

Finding largest number of observations within a given radius

I have the following problem: Given the location of insured properties (say houses with fire insurance), i have to find the largest sum of insured values which fit into a 300m radius. Now, my first ...
7
votes
1answer
129 views

Generate clusters of X points within N meters

I have a set of roughly 4,000 points in very close proximity and I need to generate clusters of 5 points, with each point no farther than 50 meters from the (mean?) center of the cluster. I've ...
6
votes
1answer
924 views

Grouping map points into fixed cluster sizes

I have a dataset of 655 lat/long pairs which I'd like to split into about 100 groups. A group should have 5-10 pairs which are geographically close to each other. Dense groups should have more ...
6
votes
2answers
798 views

how to cluster points of interest by lat lon for my WP7 app

I have alread asked this question on SO, so I appologies if duplicating this is bad form. I will link to each of the sites if I get the right answer... ...
6
votes
2answers
274 views

What are my options for Server side clustering using open source GIS tools?

I need to make a webapp that will show over 40K Points on a map. These points are all across the globe. Using WFS Service and OpenLayers, it is possible to do clustering on small set of points, but ...
6
votes
1answer
242 views

Plotting 1M+ intensity reading as custom shapes with Google Maps

I currently have a database (Mongo, atm) holding roughly 1M points of data corresponding lat/lon/intensity values that I'd like to plot over a region using the Google Maps API. Ideally, I'd like to ...
5
votes
3answers
1k views

Server side clusterer for Google Maps

After doing a lot of research on different types of clustering coordinates (server side) I am still having problems with choosing the best approach for my project. My requirements: Ability to work ...
5
votes
3answers
1k views

How to update feature positions with clustering in OpenLayers?

I have an OpenLayers 2.12 map with a vector layer with a cluster strategy. All the static behavior is how I want it. Now I'd like to add the possibility to update the features' position. I do this ...
5
votes
2answers
312 views

R packages for deriving spatial clusters from origin-destination matrix

I have a matrix of origin-destination flows and I am trying to figure out the best way to derive X number of functional spatial clusters from the data. I haven't done this particular type of analysis ...
5
votes
1answer
398 views

create convex hull polygons / cluster for sets of N points in a point dataset

I have 50k points in a feature class which I need to build convex hull or polygon for each set of 50 points that are nearby each other. I guess the question is very similar to create census areas for ...
4
votes
3answers
1k views

Need to create a collection of polygons from a collection of points

I have a set of points, which are spread over a wide geographical area. I need to be able to create a set of polygons which best represent the clustered points. In parts, some points may simply lie ...
4
votes
1answer
56 views

XYZ Clustering in Python and numpy arrays

I am looking for a method of clustering XYZ data in Python that works on numpy arrays. I know of a few sources, such as clusterpy and Pysal but have had little success with them as they seem to still ...
4
votes
1answer
563 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
104 views

How to grow several concave hulls until they completely fill a larger area without overlap?

This is my problem: I have a very large point layer with polling station locations across one country; each point belongs to a specific constituency (900k points, 4k constituencies). I wish to use ...
4
votes
1answer
594 views

Openlayers: Clustering in Openlayers.Layer.Text

I have a map that displays 5 layers of markers. Each layer is a group of POI's. I load the POIs from textfiles using var cycling = new OpenLayers.Layer.Text( "Cykling", { location:"./textfile.txt"} ...
4
votes
2answers
217 views

clustering points in postgresql to create contour map

UPDATE: To try to make this a little more simple, is it possible to create a query which selects a group of points such that each point in the group is at most X units away from at least one other ...
4
votes
1answer
178 views

How to compare spatial patterns (crime cases vs population)?

I am looking for a way to statistically compare two spatial patterns in shape polygon data (not point pattern analysis). Let's say I have a city map divided in neighborhoods (barrios), in shape ...
4
votes
0answers
290 views

How to Perform a Grouping Analysis of Points to Divide a Polygon into n Number of Sub-Regions?

I'm attempting to create n sub-regions from a polygon based on a cluster analysis of a bunch of overlapping raster layers (physical layers, eg. depth, currents, waves...). Briefly, I can create a ...
3
votes
2answers
194 views

How can I GROUP BY linear spatial clusters with PostGIS?

I have a series of points in a horizontal line, arranged into discrete spatial clusters by the underlying data pattern. Here's an example of what they look like: How can I use PostGIS to group them ...
3
votes
1answer
356 views

Find clusters of points based distance rule [duplicate]

I have some points that I need to divide into groups based on clusters of points: x <- c(-1.482156, -1.482318, -1.482129, -1.482880, -1.485735, -1.485770, -1.485913, -1.484275, -1.485866) y <- ...
3
votes
1answer
385 views

How to access the icon of a feature retrieved from text in a vector-layer?

I`m using OpenLayers to show POIs on a map. These POIs are loaded from a textfile and I`m using a Vector Layer to get it onto the map - works great. Now I want to use the cluster strategy to have ...
3
votes
2answers
932 views

How to group points into a user-provided number of clusters?

I am looking for a process in ArcGIS that takes a point feature class and groups the points into a user-provided number of clusters. I am working in ArcGIS but I'd welcome any suggestions that ...
3
votes
1answer
90 views

Spatial Classification

I am not sure what to call my problem. From this image, I have a set of classified polygons (colored). I would like a way to classify the white polygons in the image. I don’t have any attributes to ...
3
votes
2answers
588 views

Cluster Strategy different Labeling at Different Level

what I did? I am trying to plot some points using cluster strategy of openlayer using animatedCluster plugin. I have gson data as given: { "type": "FeatureCollection", "features": [ { ...