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1

I'm not specialist in diseases but have to deal sometimes species abundance distributions (SAD) with co-variables, which is methodically similar to the to disease mapping (see topic 5 at the end). Risk mapping for diseases is a common task in science and statistics. The mapping context (in terms of making maps) is not so in the technical focus, because ...


3

When modelling the distributions of species, may they be animals or plants, fuzzy overlays are typically used. For an introduction into habitat suitability modelling, I suggest you take a look at GISLounge - Overview of Fuzzy Logic Site Selection in GIS. As Michael has already pointed out correctly, you will need more than one criterion (in your case ...


4

The simplest way to run your analysis (without trying to define your actual inputs) is to do some basic raster algebra. Have a go with the raster calculator: https://docs.qgis.org/2.8/en/docs/user_manual/working_with_raster/raster_calculator.html You can build up some other vector layers too, such as 'distance to waterbody' as a distance raster. To ...


3

If you load an unreferenced raster into the georeferencer, the question for the CRS is surely useless. The referencing assings values of pixel/line to target coordinates, so the source CRS does not play any role. The target CRS however is important, it depends on the way you are doing the georeferencing. You have lat/lon grid lines imprinted on the map, ...


1

A map is not georeferenced. Shapefiles and feature classes (s/fc, for short)) can and usually do have a coordinate system, either geographic or projected. Other items, typically imagery such as a jpg or CAD data, are then georeferenced to the s/fc. Basically, georeferencing refers to the process of 'rubbersheeting' the image to known reference points in the ...


0

since the square if this image is slightly tilted, I am quite sure that this GeoTIFF is already map projected/georeferenced. Check the properties (e.g. QGIS /ArcGIS) to see which map projection it is. Actually, if you use gdal_warp on this Geotiff indicating your wanted output projection, it will probably read the existing map projection and reproject it ...


0

One way to do it is with the plugin "numerical vertex edit"(you can find it in the plugins repostory). There you can edit nodes by clicking on them and then changing their coordinates. The original coordinate is displayed in the edit-window, you can now copy them. Though I'm sure there are more elegant ways, it should do the trick.


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If the file is a tif, you can add transparency to it, either by adding a transparency channel, or with additional NODATA values. For the first solution, you might clip your data by a polygon layer of the red line. For the second solution, you can use the information tool on the raster layer, note the raster value in the black and white areas you want ...


1

I seem to have found the cause of the problem. It seems if I rotate an image using windows photo viewer prior to bringing it into ArcMap and georeferencing it, this will cause the problem (for me at least!)



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