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

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30 views

Airborne Smell Modelling

I am wondering if anyone can point me to a resource that will provide a way to model out smells of a garbage dump based on wind? I have been searching through articles on down wind pollution models ...
8
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2answers
6k views

Creating noise maps using ArcGIS for Desktop or Open Source Desktop GIS? [on hold]

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. ...
1
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2answers
569 views

Finding a Conceptual Site Modeling Software

I've been asked by my company to generate a conceptual site model for a project and I have no clue where to start. The purpose is to show groundwater flow through a few layers of rock either in 2D or ...
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1answer
219 views

What is the difference between Specific Catchment Area and Total Catchment Area in hydrology?

I am getting stuck on the concepts of Total Catchment Area (TCA) and Specific Catchment Area (SCA) as I try to learn more about TOPMODEL. What do these metrics mean in hydrology? The context I ...
12
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5answers
3k 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 ...
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0answers
22 views

Database modeling for big data (big set of points X big sets of possible values for each points)?

I'm building a PostgreSQL database with the intent to host modelisation results for different projects. Each project has a set of receptors points (~5000-10000 receptors) and have many results sets (...
2
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1answer
31 views

Spatial resolution for Bioclim datasets

I am new in using Bioclim datasets. I want to model future spread of Prosopis juliflora using landsat 30m. I want to add other datasets like temperature, ppt, elevation, soil moisture, pH, etc. Any ...
3
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3answers
261 views

Flow Accumulation Python or MATLAB Script

does anyone have any resources for scripting the D8 flow accumulation in Python or MATLAB after obtaining the flow direction values and filling in 'sinks' and 'flats'? I am trying to understand the ...
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7answers
2k 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 ...
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2answers
51 views

ArcGIS 10.2 Model Builder, getting results to 'add to display' when running as a model tool?

I have a finished model that has been saved as a model tool in a custom toolbox. I add the toolbox to ArcToolbox, double click, set the parameters, and run just like any other tool. I have the model ...
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0answers
26 views

ArcGIS 10.2 Model builder Spatial Join user input

I have a model that runs a spatial join and then adds and calculates fields to that joined table output. The model is designed so that a user can change the target features and join features. I have ...
6
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1answer
780 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 ...
2
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1answer
74 views

What methodology is used to quantify global warming?

This article in the LA Times says: The first detailed global temperature measurements were recorded in 1880. Since then, nine of the 10 warmest years on record have occurred since 2002, ...
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1answer
2k views

Difference between dynamic model and static model [closed]

I have been going through types of models in Spatial Modelling. As far as I know, Dynamic modeling is done on temporal data while static modeling is time independent i.e. it works on single data ...
2
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1answer
28 views

Identifying the best OLS regression model

I have 10 independent variables to include in an OLS regression model. I know how to interpret the results and that for comparing models, the AICc value can be used, where a smaller value indicates a ...
5
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 ...
1
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2answers
76 views

How to make input data in MaxEnt with several occurences at the same coordinates?

I have insect traps data with several hundreds insects caught every day. In this paper, authors say "Running the model using the number of mosquitoes per trap-night resulted in clustering of high ...
2
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1answer
166 views

3D model of rooftops based on LiDAR and cadastral data?

I´m trying to model building rooftops based on a LiDAR dataset. I've already interpolated using Delaunay's triangulation a DEM with 1 meter resolution. Due to LiDAR data is not accurate in building ...
7
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2answers
9k views

Is there QGIS plugin to allow 3d visualisation of geological borehole data similar to 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 ...
0
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0answers
83 views

spatial autocorrelation and calculation of autocovariate term

I was reading some literature on spatial modeling, where it is stressed that in using regression (e.g., the Generalized Linear Model family, comprising Logistic Regression for example) the possible ...
1
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0answers
42 views

Modelling zero-inflated spatially autocorrelated data with extreme values

I have spatially explicit data (above; Longitude, Latitude) with measurements on a random variable (z). This data was not collected in a random or systematic fashion, but instead was recorded ...
4
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1answer
535 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, ...
0
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1answer
128 views

Modelling soil texture using ArcGIS for Desktop?

I am doing a project for automated soil mapping using landsat TM imagery, I have 3 output rasters: one for sand percentage one for silt percentage and a third for clay percentage. How can I ...
9
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5answers
2k 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 ...
0
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1answer
63 views

joining non-spatial pollution model (csv file) to Qgis

I need help..I have csv file with concentration data but without coordinates. Start of pollution concentration connect with that one point on map. Is there any chance ? Start of pollution ...
2
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1answer
740 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
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2answers
2k views

How to resample a raster to higher resolution in QGIS?

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 ...
2
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2answers
3k views

Variogram model fit compatability among geoR, gstat, and nlme packages in R

I'm trying to specify the covariance structure parameters in a linear mixed model (using the correlation structure facilities in nlme). The parameters are estimated from a gstat or geoR variogram ...
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1answer
121 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 ...
1
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1answer
88 views

How to calculate the impact and extent of damage of a potential tailings dam breach with ArcGIS?

I would like to be able to delineate an approximate area of a potential tailings dam breach for an emergency response plan purposes. The tailins dam and pond have not yet been built. The data I have:...
0
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1answer
34 views

Implementing GLMMs in ArcGIS

I am looking to create a predictive model in ArcGIS. I have done this previously with glm with poisson distribution and found it relatively straightforward in raster calculator e.g. exp(intercept + (...
12
votes
3answers
917 views

Modelling of rent prices - which interpolation method to use?

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 ...
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2answers
142 views

Building DEM of large areas

I am putting together a compilation of 1/3 arc second, and 1/9 arc second DEM data for essentially all of southeastern Oregon in ArcGIS. This surface would be used for geomorphological and geological ...
3
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0answers
63 views

3D interpolating

Our final year project domain is soil contamination modeling. We collected soil samples at the depths of 0.3 cm ,0.5cm , 1cm , 1.5 cm in about 25 locations. We considered 8 contaminants- p h, sodium, ...
2
votes
1answer
610 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 ...
1
vote
1answer
723 views

Is there a SWAT model integration for 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 ...
1
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0answers
42 views

Best Watershed and Hydraulic Models, What is your recomendation?

I am looking to model phosphorus, nitrogen and sediment loads at the watershed and sub-watershed scale in Southern Ontario where the primary land use is agricultural. What is the best model to use? ...
4
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2answers
278 views

How to run a GAM model in GIS?

How do you generate a species distribution probability map from GAM models? Or in other words, how do you set up a GAM equation in GIS to produce probability of species distribution? It is simple to ...
15
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3answers
2k 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 ...
0
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2answers
183 views

How to bring 3D object into 3D application?

I'm doing some GIS as part of my college course and have just started to do some 3D modelling, I'm really a GIS novice, The module is short (only 5 lectures) My lecturer has said that it is possible ...
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5answers
3k 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 area ...
1
vote
0answers
88 views

Sea flow model and ArcGIS particle tracking tool

I find myself in the need to 'predict' the path and, more importantly, the final arrival point of something which is left on the sea surface, on the basis of wind direction and wind speed (leaving ...
1
vote
0answers
53 views

Data occurrence in openModeller?

I am having problems adding occurrence data to openModeller and I think that the format might be the problem. I am using Excel with the fields: #ID Taxon Name Longitude Latitude. I saved the result ...
0
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2answers
157 views

Intersecting Polygons

I have 10 shape files containing polygon features. I would like to produce a single polygon layer containing portions of the input polygons where no fewer than two of the aforementioned feature ...
1
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0answers
70 views

Creating model that simulates water flowing down crack, then splitting at 'Y' joint?

Maybe this is a simple problem, but I've been given a task of simulating how water flows in one line, along a crack, and then hits a 'Y' junction, where half the water flows in each of the split ...
4
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0answers
390 views

Preparing Huff model with data to use in QGIS? [closed]

I'm trying to find out about the notion of potential of acessibility using the methods of Huff. I´m using QGIS, with point data (with the variables that I would like to use) and polygons for Europe ...
3
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2answers
756 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?
1
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1answer
390 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, ...
2
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1answer
59 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 ...
5
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3answers
1k 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 ...