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

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3
votes
1answer
64 views

Analyzing hot spots using point attributes?

I'm interested in looking at where hot and cold spots of certain social indicators (such as poverty, housing characteristics, urban sprawl, etc...) are in coastal communities along the East Coast. I ...
3
votes
2answers
396 views

Methods for hot spot or cluster analysis for multiple measurements at the same geographic unit?

I would like to find geographic clusters of zip codes where each zip code has a measurement of a person's age (integer), sex (categorical/binary), and if they recovered from a certain medical ...
0
votes
0answers
785 views

How to draw small circles within a big circle(greater radius) on the basis of marker size on google maps?

I have more than 1000 markers at different location in my Map. I read Lat and Long from a xml file and render it in Google maps and create circle over them on the basis of city name within given ...
9
votes
4answers
588 views

Finding clusters of one set of points around another set of points from 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 ...
0
votes
2answers
139 views

how to make clusters from small polygons with constraint of boundary touching?

I want to make some clusters from a bunch of small polygons with the constraint that each basic unit (polygon) in the resultant cluster must share a portion of its boundary with at least one other ...
3
votes
2answers
260 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 ...
1
vote
0answers
109 views

How to show hierarchical clusters in google maps or other tool?

Google maps marker can be clustered but those clusters expand on different levels. I want to stay on a specific zoom level and cluster a set of markers. Then I want to show sub clusters inside that ...
11
votes
2answers
219 views

Identify points in a shapefile that have no other point within x km with QGIS

This is probably a naive question but I am struggling as a new user to QGIS. I have a very large shapefile (275,000 points, but can break this into about 10 subregions if necessary for faster ...
1
vote
1answer
45 views

Assign points with varying radii to central meeting locations

I have a set of points in a city, each with a maximum distance radius of 0.5 - 1.5 miles. From this set of points, I'd like to create a small number of 'meeting points', i.e. locations that are ...
0
votes
0answers
36 views

k-NN Search with GIS dataset

I have made a k-NN search algorithm in matlab, and I want to implement it using a GIS data-set. A Google search didn't yield any good test data-sets. At this point, I have created a data-set by taking ...
2
votes
1answer
104 views

Create a grid with statistics of the merged shapefiles in QGIS

I operate with QGIS. I have to split the shape files of the buildings and the roads of a city into a grid of 500x500m per square and into each square I have to obtain the total free area, the total ...
2
votes
2answers
609 views

Remove clumps of pixels in R

I would like to remove isolated pixels (or clumps of pixels <9) from my raster image. library(raster) # create some raster data r <- raster(ncols=12, nrows=12) set.seed(0) r[] <- ...
0
votes
0answers
408 views

K-means cluster analysis with initial centers with ArcGIS

I am trying to figure out a way to make a K means cluster analysis using initial centers for the clusters, and only classifying, no iteration, for the features in a feature class. Having a feature ...
1
vote
2answers
87 views

Is it valid to adjust quantile buckets to “nice” numbers for better readability?

I'm making a map about terrorist attacks and fatalities in CartoDB. For data clustering I'm using quantiles. The calculated buckets are 16, 32, 50, 97, 700. Is it okay to adjust the quantiles to make ...
1
vote
0answers
51 views

How to organize/cluster nodes moving on the same direction

The Problem I am working on a problem of clustering for mobile nodes. Initially, I though of clustering the nodes based on their angle of movement (relative to the x-axis). However this situation ...
2
votes
1answer
276 views

Fast Clustering Algorithm for Geographic Data?

I have been browsing through the net in my attempt to find a fast clustering algorithm to cluster geographic points, but lot many of the results found were for clustering algorithm in general and not ...
2
votes
3answers
698 views

Server side clustering - cluster (feature) geometry

I am trying to implement server side clustering and show it using OpenLayers. I am using this good material as an example. As a clustering result, a get some list of features, some of them are ...
1
vote
0answers
79 views

How to Create Polygon shapefile based on change in point value?

Is there a function in ArcGIS that would take analyze the adjacent point or polygon based on percent difference. If the adjacent value is within less than the percent it would dissolve otherwise ...
3
votes
1answer
200 views

Hot Spot Analysis using ArcGIS for Desktop?

I have a point shape containing locations of cars and a line shape containing roads. Now I want to identify hotspots/clusters. I want to find hot spots where for example the speed of the cars is ...
0
votes
0answers
271 views

Creating the Regions based on spatial clusters

I need to create areas for my shapefiles for spatial analysis for each. So I have a number of stations and I created 5 clusters based on the distance. code: Al <- ...
2
votes
1answer
503 views

Leaflet Marker-Cluster JSONP GeoServer

I hope I can get same help from here. I started to put together a leaflet map, please see here: http://gis.xyz/leaflet2.html I want to show my postgis point (uk based) features on this map with ...
2
votes
1answer
887 views

Get a single cluster from cloud of points with specified maximum diameter in postgis

I have on the order of 2M Geometry Collections with N (median: 2, stddev: 6.6, 75th: 6, 95th: 21) Point objects (repeated points allowed and important) in a PostGIS table. I want to identify clusters ...
2
votes
1answer
98 views

clustering map (North, Centre, South) in R

I am looking for a method to partition map in 3 groups (North, Centre, South) like this: how to do this in R please stations.txt Code : Al <- shapefile("DZA_adm/DZA_adm0.shp") # read in ascii ...
1
vote
1answer
159 views

Visualize large amount of geopoints with Geoserver and PostGIS

I have a postgis database with over 50 million rows. Every row consists of a POINT corresponding to lon,lat and a value (number 1-100) I'm trying to create tiles for zoom levels 5-20 that I want to ...
1
vote
1answer
361 views

Leaflet - GPX - Clustering

I'm using Leaflet maps together with "Plugins by Pavel Shramov", which allows google usage and GPX file use. This bit was easy enough, but trying now to use markerClusterer. I've spent a few hours ...
2
votes
1answer
1k views

Changing size of cluster based on number of markers in Leaflet clustermarker

I'm currently using Leaflet's markercluster add-on, which is working really nicely for some of my initial maps. However, I'm wondering if there is a way to modify the clusters so that the size of the ...
5
votes
3answers
2k views

Creating collection of polygons from 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 ...
3
votes
0answers
51 views

How to set m parameter of clusterR function in R?

I want to manage a clustered computation on raster and thus use the "clusterR" function in R (package 'raster'). However, there's a tuning m parameter to set, but the only explanation about this ...
16
votes
4answers
2k 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 ...
5
votes
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 ...
4
votes
1answer
171 views

How to create a cluster of crashes?

I have a shapefile with 52K points of road accidents, between 2007 and 2012. Each accident has a severity index. I want show clusters of 5 accidents (at least), for each year, that have a severity ...
23
votes
7answers
1k 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) ...
9
votes
1answer
2k 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 ...
1
vote
0answers
28 views

Grouping map points into fixed cluster sizes? [duplicate]

"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 ...
2
votes
1answer
440 views

Leaflet/MarkerCluster plugin - how do update the HTML content of a DivIcon?

In Leaflet, I am using the markercluster plugin, in which you can use the DivIcon class to display custom icons for the clusters. You can set your own HTML for these clusters. However, I can't find ...
1
vote
0answers
26 views

Creating single feature to represent group of individual features, based on location and #, using ArcGIS Desktop?

I am looking for an algorithmic way of handling this situation, as I can do it manually with the ruler and some time, but it would be nice to find a programmatic to have Arc do the work for me, so any ...
4
votes
1answer
406 views

How to find mean coordinates of a cluster of points from a point layer in QGIS?

I have a set of coordinate points. The points are distributed in such a way that some points are clustered around a specific area. There is an option to find out mean coordinates(s) of the whole point ...
-3
votes
1answer
490 views

CartoDB Point Clustering?

I need to create clusters in Cartodb. I reffered to this code https://gist.github.com/andrewxhill/8695353. I am still getting an error. <!DOCTYPE html> <html lang="en"> <head> ...
1
vote
0answers
128 views

Clustering the WGS84 point features (projection transformation aspects)

My question is quite trivial and was discussed many times before (like here) but in our case it has the confounding extra requirements... The list of sparsely distributed 2d point features is stored ...
1
vote
0answers
122 views

Clustering on Geoserver layer appearing out of the map

We are using Geoserver and openlayers to display maps. Geosever layer provides list of sites, since there were many we did a clsutering using Styles. But the problem is when we zoom out completely ...
5
votes
1answer
449 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 ...
1
vote
0answers
267 views

Finding areas with high POINT density from PostGIS table using Python

I have a PostGIS table with thousands of POINT objects and I want to find areas that have a high density of points. I have the DBSCAN clustering algorithm implemented in Python which does exactly ...
3
votes
1answer
4k views

How to use Leaflet Marker Cluster on markers from Leaflet-layerJSON (Overpass API)

I'm having troubles getting the Leaflet Marker Cluster working with Leaflet-layerJSON. I'm trying to make a Leaflet map with data from OpenStreetMap. The markers are showing on the map, but they are ...
0
votes
1answer
56 views

Error when running cluster and outlier analysis

I am attempting to run Cluster and Outlier Analysis on a Shapefile Feature Class. The geometry type is a line feature class. I am receiving the following error when attempting to utilize this tool: ...
7
votes
3answers
352 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 ...
3
votes
1answer
1k views

How to cluster Raster data

I have thousands of Raster data concerning the ice coverage at the pole at different times (days) over several years. Now I would like to perform a cluster analysis. I want to split the data into ...
1
vote
0answers
198 views

Monte Carlo test of Space-Time clustering in R

I have several point patterns representing the distribution of territories of a bird species. Each point pattern represents the distribution of one year. I already succeeded in computing Ripley's L ...
1
vote
1answer
487 views

How to disperse clusters of proportional markers or polygons?

I am mapping a set of points in ArcMap that are symbolized using proportional marker symbols based on a numeric field value. The scale of the map has lead to alot of the point markers overlapping. ...
6
votes
1answer
1k views

How to get the centroid of a set of points in POSTGIS?

I use PostgreSQL with POSTGIS extension. I have a set of points in the_geom column from a table myshema.myobjects I would want create a select statement to get the centroid of this cluster, so from a ...
3
votes
0answers
46 views

Algorithm for estimating position of many objects and differentiating those?

Let's assume a crowd-sourced tree location use case where a research team asks hikers to GPS the location of a specific tree type in case they encounter it. This will lead to a large number of ...