A methodology or set of analytical procedures used to derive information about spatial relationships between geographic phenomena.

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17
votes
1answer
824 views

Gravity/Huff model tools

I am looking for a way to simulate a gravity model using a point-based layer. All my points are assigned a z-value and the higher this value, the larger is their "sphere of influence". This influence ...
16
votes
4answers
583 views

How to handle TIME in GIS?

Is there any way or any idea on how to handle Time attribute in GIS? For example, which are the ways to specify that an object is at a place at a given time interval and them it is in another place ...
16
votes
3answers
527 views

Lightsquared GPS controversy: Where is the analysis?

GPS World reports that Lightsquared's network of 40,000 transmitters will interfere with GPS signals. Initial technical analyses have shown that the distant, low-powered GPS signals would ...
14
votes
3answers
993 views

Is there a CASE Tool for modelling spatial databases?

Does anyone knows if there is a CASE Tool that would be possible for modelling spatial tables? I need to create a model and export it to SQL or a database directly. I´m using PostGIS. Thanks in ...
13
votes
5answers
1k views

What are some 3D visualisation tools that successfully work with GIS data?

There are a large number of 3d modelling tools available (both open and closed source). I would like to be able to: Import GIS data into a 3d environment and retain georeferenceing. Retain the ...
12
votes
5answers
2k views

Where are the radiation models for Japan catastrophe?

I'm interested in seeing authoritative model results showing how radioactive contaminants from Japan might circulate through wind and water. The AGU blog points out this bad model, but in skimming ...
12
votes
3answers
275 views

What practices are available for modelling land suitability?

I currently use a "classic" raster based approach of dividing a study area into cells. All input layers are converted to rasters at the same cell resolution and given a suitability rating. A final ...
12
votes
1answer
1k views

Open-source GIS implementation of the Huff model

This might be a stretch, but I was wondering if anyone implemented gravity modeling tools or scripts for Retail Market Analysis (like the Huff Model), to analyze spatial data for customer-store ...
11
votes
3answers
503 views

Modelling of rent prices - which interpolation method should I choose?

I have national dataset of ~1,4 million households. There I have information about rent, size (number of rooms and m2) and some additional characteristics of each household. I'd like to use this data ...
11
votes
5answers
440 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 ...
9
votes
3answers
283 views

Application of GIS in passive and agent defence

I am working on passive defense modeling, using GIS. Modeling passive defense can be better implemented using GIS and I've come up with my own methods. It would be far better for me if I know there ...
9
votes
2answers
299 views

Ocean flow models - predict the path of an object dropped in the ocean

This question is from a user who wants to calculate the predicted path of a bottle dropped from a ship. He has a spreadsheet of hundreds of these bottles and wishes to display the predicted vs actual ...
7
votes
1answer
4k views

Is there are QGIS plugin to allow the 3d visualisation of geological borehole data similar to the functionality of Target for ArcGIS?

I'm very new to QGIS, I have started using it as my new company is not willing to pay for ArcGIS and Target at this stage so I'm hoping QGIS can substitute not just in the interim but for good. What ...
7
votes
7answers
825 views

seeking “Available Sky” implementations

I'm looking for implementations of an algorithm called "Available Sky". ArcGIS (Spatial Analyst or GRID) is preferred, but solutions in GDAL, SAGA GIS or others are perfectly acceptable. The ...
7
votes
2answers
2k views

Creating noise maps using ArcGIS for Desktop or Open Source Desktop GIS?

In a previous role I helped create Noise Maps for Northern England. The predicted noise levels was done using the IMMI package (which I can recommend) and the cartographic output was done in ArcMap. ...
7
votes
1answer
282 views

Looking for examples of bayesian modelling and smoothing in a GIS

I am looking to assemble clear examples of Bayesian modelling / smoothing in a GIS. I have yet to see GIS being used to conduct Bayesian style analytical models and would like to see what is currently ...
6
votes
1answer
416 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 ...
6
votes
1answer
603 views

Open source location allocation modelling

I'm looking for open source tools for location allocation modelling (eg planning public health facilities). Preferably in a GIS environment. I know GRASS somewhat, but v.net.alloc doesn't seem to ...
5
votes
3answers
2k views

3D subsurface modelling

I am a student and initiating a thesis project for MS specialize degree in geophysics... I am working on tectono - stratigraphy of some area and want to do the 3D subsurface modelling of the same ...
5
votes
3answers
427 views

How to calculate changes in slope angle between cells/areas?

I am doing an estimation of erosion with ArcGIS. I use the UniversalSoilLossEquation (USLE) for this. Now, i want to calculate the L-factor of this equation. I need the FlowLength for this. My ...
4
votes
1answer
297 views

SQL Server data modelling + spatial data = what book?

What recommended book can you provide about data modelling for geographical spatial data (geometry) in SQL server?
4
votes
2answers
1k views

compound variables in model builder?

I'm trying to create a model wherein one of the parameters is a compound variable, that is made of multiple variables joined together. How can this be done? For Example: Create an insider buffer ...
4
votes
1answer
234 views

Moving window regression (MWR) in R

I'm looking for some package in R to estimate the value of a variable by moving window regression. I have read in Local Models for Spatial Analysis, which is a good method to predict values ​​at ...
4
votes
1answer
417 views

What do I need to create 3D model of real terrain?

I'd like to create 3D model of some real terrain (to be exact it's about some real roads and only as much as 80m to 100m of roadside - 40m to 50m of each side). As I don't have access to highly ...
3
votes
1answer
425 views

Are there open source solutions for travel demand modelling?

I'm looking for open source tools for travel demand modelling (eg The four-step UTMS). Preferably in a GIS environment. That works well with Qgis, Grass and Postgis. My question is not related to ...
3
votes
1answer
178 views

Get points in point file to write into new field the census tract each is in (from another shapefile)

I have points that represent day care centers which have address and lat-long. I am using lat-long to display. Now I need to sort, count, etc. these points in conjunction with new census data. To be ...
3
votes
2answers
473 views

Land Administration Domain Model example implementations

Does anybody know of a sample implementation? I am currently trying to adapt it to my country but the LADM is rather abstract. Anybody have any idea how to go about this?
3
votes
1answer
269 views

Looking for Fortran code calculating drainage basin area

I am working in a project of glacier mass balance. For my project I want to integrate the area of the drainage basin in a glaciological system model (GSM). As the drainage area changes with time due ...
3
votes
1answer
323 views

Enterprise Architect - domains relationship

I am not sure if this forum is right place to ask but let me try. I am building an ArcGIS model in Enterprise Architect. I have a couple domains inside. The problem is: I want to make the following ...
3
votes
1answer
301 views

Displaying 3D subsoil models in ArcScene

I was wondering if anybody had any ideas on how to display a 3D subsoil model in arcscene? The data we will have will be exported from rockworks in point form - and then we need to convert it to - ...
3
votes
1answer
81 views

Is there ArcGIS (ideally) solution for spill modeling from particular pour point on crude oil pipeline?

wondering if anyone knows of a solution for spill modeling from a particular pour point on a crude oil pipeline? I currently have all my data within ArcGIS (DEM, major/moderate/minor watercourses, ...
2
votes
1answer
120 views

How to multiply raster DEM with a linear graph value

I would like to multiply my Raster DEM with a linear graph value y = mx + C. The graph values look as follows: I want to make a new raster where each cell will represent a damage factor from ...
2
votes
1answer
145 views

Attributes that characterize a geodetic track

I need a way to index and retrieve a large amount of track data. To do this I need to derive from every track as many attributes as I can. For now, I derive Name Tortuosity Speed (average, max) ...
2
votes
1answer
95 views

How to Improve a Distance Model

I am working on a distance model that creates distance rings around a given point and assigns those rings a probability. The point is in the center of a 25 x 25 km area, and the model fails to assign ...
2
votes
1answer
24 views

Modeling data in PostGIS when Several Join queries with Geometry are Needed

Suppose you have a database where you have several tables with geometric information and you have several cases in your system where you need to query the tables with a lot of joins (ie: LEFT JOIN ...
2
votes
1answer
96 views

TRANSIMS interaction with OSGEO tools

Wow I've just discovered the world of TRANSIMS, a transport model with ambitious aims: "to model all aspects of human behaviour related to transport in one consistent simulation framework" (Nagel, ...
2
votes
1answer
344 views

Inverse distance weighted interpolation for categorical and/or binary datasets

I want to perform an Inverse distance weighted (IDW) interpolation to a series of points. However my data set can be categorical or binary and just like the IDW I want to interpolate the new values ...
2
votes
1answer
256 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
votes
0answers
120 views

Modelling Zombie Outbreak

I know that there are many scripts (mostly in matlab) out there that address the spread of disease/zombie infection, but does anyone know of ways this has been developed/implemented in ArcGIS? ...
2
votes
0answers
205 views

Incorporating known GPS/INS data to automatically produce geo-registered 3D models

I am trying to reconstruct a 3D building model from 2D video frames using an open-source Structure-From-Motion(SFM) software (Bundler). The final reconstructed 3D model will be in Cartesian ...
1
vote
1answer
61 views

Infrastructure networks in GIS modelling

I am currently working on a GIS-based project which aims to model the interdependency of existing infrastructure networks, e.g. transport, oil, pipeline networks, etc. The network interdependency ...
1
vote
2answers
115 views

Routing and Travel Time

I wish to generate highways network routings and travel times from trip pairs. The trip pairs are between the centroids of UK census Lower Super Output Areas. For each trip pair (perhaps 5,000 records ...
1
vote
3answers
2k views

Calculate XY Coordinate with “CalculateField” tool

I used model builder to build a model which can calculate the XY coordinates and it's perfect! However, when I export it to VBscript and run it in VBA it crashes.... The error happens at ...
1
vote
1answer
44 views

rasters as independent variables in logistic regression: must they have the same values classification?

I am planning to build a predictive model for land productivity using arcGIS 10.1. and logistic regression. In my model, the Independent Variables would be, among others, distance from rivers, ...
1
vote
1answer
67 views

rooftop modeling

I´m trying to model building rooftops based on a LiDAR dataset. I've already interpolated using Delaunay's triangulation a DEM with 1m resolution. Due to LiDAR data is not accurate in building edges, ...
1
vote
1answer
414 views

Issues Merging in Model Builder after Running Script

I have multiple inputs running through various processes throughout my model. At the end of these processes they are all merged together and output into one final feature class. This was working fine ...
1
vote
0answers
70 views

Using SWAT model with QGIS

I am trying to use SWAT (Soil and Water Assessment Tool) for watershed management activities. It is a set of commandline tools and needs a complex set of input data some of which can be generated from ...
0
votes
2answers
48 views

Is it permissible to redefine raster resolution (not resample!) in order that it be included in a SDM?

I'm fitting a SDM using R. A requirement is that all environmental predictor layers have the same extent, origin and resolution. I have high resolution bathymetry data (25m) that I will resample to ...
0
votes
1answer
117 views

How does ModelBuilder compare with Vensim and Stella for environmental modeling? [closed]

Does anyone have any advice or has anyone experienced any limitations in ArcGIS software when trying to use model builder for any type of environmental phenomenon? I know that Vensim and Stella can be ...
0
votes
1answer
294 views

How do I choose parameters for the Huff model that best fit my data?

I'm using the Huff model for some analysis I'm doing. For those not aware, the Huff model is a probabilistic model for retail trade area analysis. H_ij is the probability that a person at location ...