Questions tagged [confusion-matrix]
A confusion matrix contains information about actual and predicted classifications done by a classification system.
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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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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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Legend for confusion matrix in R
I have created a confusion matrix plot in R however I would like to get the legend that shows the values for the colours. How would I do this? So far I have the following:
z = c(135,9,0,7,0,0,55,3,
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Confusion matrix plot in r
I have a computed confusion matrix from google earth engine that I would like to use in r to derive a plot. how do I manually enter the confusion matrix and plot in R?. This is the confusion matrix:
1:...
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In Google Earth Engine (GEE) what is the difference between ConfusionMatrix() and errorMatrix()?
In the process of evaluating the classification of a satellite image, it is verified that the GEE has two available commands: ConfusionMatrix() and errorMatrix(). In some literature I see that both ...
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Compute confusion matrix using own attribute table in ArcGIS Pro
I have a study area that I defined using polygons (Not using ArcGIS classification types such as supervised pixel based etc). I then went in to the field and collected ground truth data within these ...
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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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Accuracy assessment of land class covers in ArcGIS
I want to compare the accuracy of citizen scientists in mapping a satellite image by using a raster labelled by an expert as my ground truth.
How can I do this in ArcGIS Pro?
What I've tried so far:
I'...
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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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Creating formatted chart for Confusion Matrix using Google Earth Engine
I was curious how to create a formatted Confusion Matrix: (https://developers.google.com/earth-engine/apidocs/ee-confusionmatrix)
I've completed my Supervised Classification, and I've created a ...
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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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Confusion matrices for two lists of raster objects
I have two lists of raster objects. One contains validation plots and the other contains results from a random forest binary classification of those plots. I would like to loop through both lists ...
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How to exclude/eliminate invalid areas (such as NoData, cloud, water, etc) from raster so that it does not effect the accuracy assessment?
I have two classified raster (snow cover % 10-100) one is prepared from coarse resolution and another is from finer resolution. I am doing accuracy assessment and matrix calculation of snow cover %. ...
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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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Get a Confusion matrix in QGIS from two vectors
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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Splitting up a region into training data and validation data for Landsat7 classification
I am building a classifier for Landsat7 by using MODIS land cover classification.
My goal is to split up my region of interest into 80% being training data and 20% being validation data (with a ...
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Change size to the squares of the confusion matrix [closed]
I have a problem with size in the 'plot_confusion_matrix', the squares of the confusion matrix appear cut off. I would like to solve this problem.
svc = SVC(kernel='linear',C=1,probability=True)
svc....
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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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Generating confusion matrix using classified image with geotiff format?
I am working on yielding a confusion matrix with importing an image which is a geotiff format. After classified by a python program, The image has two values (two classifications). However, when I ...
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Confusion Matrix R
I'm having some problems to understand the result of my confusion matrix. Here is my case:
I've run a classification (random forest) on a satellite image. To do so, I created 50 random points for ...
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Ground truthing with Google Earth
I need to obtain ground truth data of Google Earth for a certain region for the purpose of constructing confusion matrix. The data should correspond to Landcover classes.
My main aim is to construct ...
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Classification validation: Trouble with the Confusion Matrix
I'm supposed to validate my supervised classification with a Confusion Matrix, but I'm having a hard time getting what I should use as a comparison.
At first, I used the same ROIs I created for ...
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Confusion matrix in ArcGIS 10.3
How can I get a confusion matrix using specific columns in two different rasters in ArcGIS ? I have one raster of risk classes 1,2,3,4 and another raster of land cover A, B, C,D. I am looking for a ...
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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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Random Forest out of the bag and confusion matrix
I have implemented Random Forest classifier to classify remote sensing data in R. The original code comes from here:
How to perform Random Forest land classification?
Everything works fine, but what ...
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How to interpret accuracy assessment results for classified data?
eCognition has the ability to perform an accuracy assessment for classified data by using an error matrix based on a TTA mask. The image shows the results of the accuracy assessment.
Is there a ...
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R: creating an error matrix from two rasters
I have two land use rasters (6 classes each) and I'd like to create an error matrix (errors of omission and commission) from them both.
The premise is that I have a very fine 'base' raster and have ...
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Remote sensing accuracy assessment - McNemar`s Test
I would like to know how you determine the f12, f21 parameters for use in the McNemar`s test when for example I have two confusion matrices such as below:
(where f12 = number of cells misclassified ...
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Doing Accuracy Assessment using test data from shapefile in ENVI?
ENVI 5.2.1. From a .tiff image (4 bands) I created a Supervised Classification Maximum Likelihood .dat file. Now I want to perform an Accuracy Assessment using test data from a shapefile. I've tried ...
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Building confusion matrix for image classification using SAGA?
I did a supervised classification of a Landsat image subset using my training data polygons. I used SAGA GIS for that and everything worked out fine. Now I am stuck since I have no clue how to ...
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