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Dear Andrew and Eric, thank you for your responses. I have to admit I am a little confused about the fundamentals of this issue. But let me ask a few straightforward questions to see if I can at least understand the implications: 1. The values I see in the voxel layer do come from the EBK3D analysis. That the EBK3D didn't show them to me before is because it has made its (and our) life a bit easier (runs quick) by visualising a triangular grid and 'spreading' the range of values of the original data set over it? 2. That means that whatever export format I choose for the statistical layer (for example 'to points') I will obtain the values that I now see in my voxel layer? 3. Some of the values I obtain are nonphysical (i.e. the negative values), does this not mean something is fundamentally wrong about the statistical analysis? Especially if the values are really quite different from the original data set (for example if my data ranges from 0.1 to 80 and the voxel layer shows results between -20 and 60)? 4. Wouldn't adjusting the min/max range in the above mentioned case from -20 and 60 to 0.1 and 80 be cheating? It seems I would then be ignoring what the geostatistical analyst has told me.. Thanks again in advance! Suzanne
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10-12-2020
02:10 AM
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Hey, I actually have a question about the voxel space data. How come the range is different for the EBK3D predictions and the voxels? Especially the negative values surprise me.. Suzanne
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10-09-2020
01:48 AM
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Dear Andrew and Eric, Thanks so much, you were right! The coordinates of the voxel, EBK and data layers matched, but they didn't match with the local scene coordinate system itself (I didn't know that it also has one..). Here some pictures of my results : Eric Krause and Philip Mielke thanks for your help with making this work - and even better than I thought! My next challenge will be to export the EBK3D data in a way such that I can use it as input for hydraulic conductivity fields for a Modflow model. I'm guessing the best way to go forward is to use the Layer 3D To Feature Class. I will have a look at that, but might be back to pick your brains on it again later Regards, Suzanne
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10-08-2020
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Dear Eric (and Phil), I have tried again to get the isosurface, but I do not manage. I follow the steps exactly as indicated in the lesson you sent me. I created the .nc file, but when I want to add the multi-dimensional raster layer I get the following warning: Despite this warning, it does create this menu for me but it doesnt show me anything and tells me I also tried right clicking on the Surfaces box and say 'create isosurface' but it doesnt do anything. Any idea what might be going wrong? Thanks...! Kind regards, Suzanne
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10-06-2020
01:43 AM
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Hi Eric, I am not sure that is the problem, if I try for example to change the symbology, I get this message: I wonder if that might also be the reason I cannot find the voxel exploration pane at all... Suzanne
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09-24-2020
07:17 AM
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Hi again Eric and Phil, regarding the voxel experience: indeed I needed to download the latest version of 2.6! I created the NetCDF file using the GA Layer 3D to NetCDF tool. I then added the voxel layer. However, when I then want to create the isosurface, nothing happens.. I think that it is trying to create the layer (at least I can 'pause the drawing' see pic) but doesnt get there.. I get no error messages or so. Any ideas what goes wrong? Regarding Eric's comment about the cross validation: Indeed the data that I put in is very course. Most data points have the 'value': 'medium grained sand'. Then there are a few locations with course sand and some with clay. The bulk of course grained sand I have given a hydraulic conductivity of 15m/d, but of course in reality these values might locally vary between say 5 and 25m/d. I will play around with the other EBK3D parameters as you suggest and also add a measurement error column in my input file and see what that does for my results. Cheers, Suzanne
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09-24-2020
03:44 AM
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Dear Eric and Phil, Again, thanks a lot for both of your inputs. For the most bottom layers of my data I had fewer than 10 data points. I have now left these layers out and it works 🙂 I looked at the predication map and used the empirical transformation and an exponential semivariogram model type (I didn't see a big decrease in the error when I used K-Bessel.). See pictures below (at 30, 50 and 59m-bg resp). I also included two screen shots of the EBK analysis and the histogram of my data. Looking at the prediction vs measurement map, the EBK results also don't seem amazing (to my unexperienced eye). I am wondering to what extend the locations of my data points have to do with that. As you can see from the top view, they are not very evenly distributed. Prediction maps: EBK 3D analysis: Histogram of my data: Of course now I have some new questions.. Question 1. I would love to create an isosurface in voxel space as Phil suggested, I saw the esri video on it and it looks really amazing. But how? According to the esri website I should find the option under the add data tab, but I only find the multidimensional raster layer. I thought I start by trying out this multidimensional raster layer. I first created a netCDF file by exporting the 3D EBK results as point features, but I get an error when uploading. This might have to do with the fact that I don't know what to fill in under the 'feature to netcdf' menu.. Phil, I would be very curious to learn how you create isosurfaces in voxel experience. Question 2: The EBK supplies us with an optimal fit to the data. If I would want to create different fields (to have best- and worst case scenarios) I understand I need to look at quantile surfaces, in which I could choose to study what my outcomes may be if my measurement values are either over- or under estimated. Condition for using quantile surface is that a multivariate normal distribution can be assumed. I am not sure what that means in my case, after all, I have used the empirical transformation to be able to work around the fact that my data is not normally distributed. Very greatful for your support! Suzanne
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09-23-2020
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Hi Eric, thanks, I'll have a look at where I get to with EBK and let you know!
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09-23-2020
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