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

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1answer
41 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, ...
3
votes
3answers
118 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 ...
2
votes
1answer
20 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 ...
0
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0answers
67 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 ...
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1answer
624 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 ...
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2answers
41 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 ...
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0answers
53 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
38 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 ...
0
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1answer
99 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 ...
0
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1answer
57 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 ...
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0answers
47 views

Creating a field calculator function that can cast string to a percentage value in a related field?

I am having issues trying to create a field calculator function based on a coded domain string parameter combined with a numeric field to obtain a percentage output. The example in question is as ...
1
vote
1answer
75 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 ...
1
vote
1answer
92 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 ...
0
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1answer
22 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 + ...
1
vote
2answers
113 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
votes
0answers
59 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, ...
1
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0answers
39 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
votes
2answers
202 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 ...
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vote
0answers
68 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
42 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 ...
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0answers
66 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
votes
0answers
311 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 ...
2
votes
2answers
2k 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 ...
1
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1answer
293 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
votes
2answers
830 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 ...
1
vote
1answer
609 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 ...
2
votes
1answer
51 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 ...
4
votes
1answer
438 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
votes
2answers
423 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 ...
0
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2answers
144 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 ...
0
votes
1answer
337 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
2answers
162 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 ...
1
vote
1answer
113 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 ...
2
votes
0answers
321 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? ...
0
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0answers
62 views

High resolution global land cover [duplicate]

I'm searching for world land cover data with higher resolution than the global land cover. I'm working on fire prediction algorithms and I want to do a nice browser based demo were you can select a ...
2
votes
1answer
250 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 ...
9
votes
3answers
442 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 ...
8
votes
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 ...
4
votes
1answer
531 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 ...
1
vote
2answers
222 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 ...
2
votes
1answer
124 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 ...
0
votes
0answers
541 views

Which is the best interpolation method for collected ground water sample?

I have collected ground water quality samples from 50 locations in my study area. Now I have to interpolate data in ArcGIS. Which is a suitable method for ground water interpolation and why?
0
votes
1answer
767 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 ...
5
votes
3answers
915 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 ...
7
votes
2answers
5k 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. ...
4
votes
1answer
643 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 ...
2
votes
1answer
144 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, ...
23
votes
1answer
2k 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 ...
2
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1answer
685 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 ...
14
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5answers
1k 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 ...