Questions tagged [confusion-matrix]
A confusion matrix contains information about actual and predicted classifications done by a classification system.
12 questions with no upvoted or accepted answers
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Getting confusion matrix from two vectors in QGIS
How and with what QGIS tools can I get a confusion matrix from a vector polygon layer as a verifiable classification and a vector point sample layer as a reference classification?
That is, if the ...
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Confusion matrix from two shapefile fields in QGIS
I have a shapefile with two columns one with joinreal and predicted values. I would like to calculate the confusion matrix between these two columns.
I tried something in PyQGIS, but it does not work
#...
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Confusion matrix from supervised learning
I am performing a supervised classification in GEE and want to verify how well my classifier has got trained.
For this, I found a method confusionMatrix() and my respective program is
var training = ...
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Fatal error using orfeo toolbox (otb 8.0.0) algorithm Computeconfusionmatrix in QGIS 3.22
I tried to compute a confusion matrix of a raster classification with otb's Computeconfusionmatrix using vector data (polygons) as reference input. When I run the same algorithm in mapla (otb ...
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When creating a confusion matrix, can you have more ground-truth points than the recommended 10-times the number of classes you have?
Using ArcGIS Pro, I classified a field of grain sorghum (supervises, pixel-based support vector machine) using 5 classes: Soil, Shadows, Leaves, Heads, and Ground targets (this was a UAS study). The ...
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Supervised Random Forest in R
I did an image classification using random forest algorithm in R. I got the result but I do not understand what does the confusion matrix shows ? I mean what does the rows and column show?
These are ...
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Creating sample points that cover all values of underlaying raster using R
I need to create sample points to extract the values of a predicted raster. The values correspond to the predicted classes and are NOT occurring in the same number. In order to be able to create a ...
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What's the use of ImageCollection.errorMatrix() in Google Earth Engine?
In the docs there are two versions of the errorMatrix function:
ee.FeatureCollection.errorMatrix
and
ee.ImageCollection.errorMatrix
I've been sampling points from my classified images to create error ...
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Accuracy of threshold images
I am studying on identifying flood zones using Google Earth Engine.
I calculated the NDWI index for the Sentinel 2 image. Then I set a threshold according to the OTSU thresholding method.
I classified ...
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Accuracy assessment in GEE with an external data source
I'm new on GEE and I'm trying to perform an accuracy assessment of a supervised classification from S1 of a flood area, by the use of a confusion matrix.
Once the model is created, in order to ...
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Confusion Matrix in ArcGIS Pro not for accuracy but comparing two raster
I am wondering how to calculate or process confusion matrix on ArcGIS or other software for two raster data?
I have tried to do it on ArcGIS by create accuracy point (~700 random point) to get the ...
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How to redesign confusion matrices from Ecognition with python and seaborn?
I am using eCognition manual classification as a baseline for performance comparison with other 3D classification methods. For each method, I am creating confusion matrices in python with sklearn and ...
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