Questions tagged [confusion-matrix]
A confusion matrix is a special contingency table used to evaluate the predictive accuracy of a classifier. Predicted classes are listed in rows and actual classes in columns, with counts of respective cases in each cell.
37
questions with no upvoted or accepted answers
3
votes
3
answers
3k
views
How do I calculate the range of a F1-score from a confusion matrix of 3 class,A,B,C
Is there any support function to calculate the average F1-score range?
- 31
2
votes
1
answer
2k
views
Plotting confusion matrix for multi classification problem
I am using google colab to solve a multi-classification problem. I am trying to plot the confusion matrix for this problem, I have tried doing so using :
...
- 145
2
votes
1
answer
101
views
Why rejection of a true null hypothesis is called type I error?
I’m comparing two confusion matrices:
https://en.wikipedia.org/wiki/Confusion_matrix#Table_of_confusion
https://en.wikipedia.org/wiki/Type_I_and_type_II_errors
The 2nd is rotated, the Decision is on ...
- 21
2
votes
0
answers
229
views
Do I use class weights to penalize false negatives or threshold optimization to improve recall?
I built a Random Forest model for a binary classification problem.Both the classes in the target variable are balanced. My main class of interest is 'class 1'.
False negatives are more costly to me, ...
- 21
2
votes
0
answers
1k
views
what's the best way to plot a confusion matrix in a multilabel setting?
In a multilabel setting a training example could be a, b, (a, b), d, c, (d, c), etc. This makes it a bit hard to come up with a helpful confusion matrix because the ...
- 272
1
vote
0
answers
79
views
Azure AutoML: decimal numbers in confusion matrix
I have been running Azure AutoML on a binary classification task. When I visualize the performance and the confusion matrix in particular, I observe the following:
How can I have decimal numbers in ...
- 111
1
vote
1
answer
830
views
Difficulties in create a confusion matrix in R for Yes or No
I am new to regression and confusion matrix and trying to create a confusion matrix from logistic binary regression model. I am trying to create a confusion matrix from Yes or No values from the ...
- 35
1
vote
0
answers
50
views
Confusion matrix of 3*2
I would like to include confusion matrix in my research report. I have a binary classification problem. The positive class is further divided into two types for example: Real Positive and Obstruction ...
- 21
1
vote
0
answers
34
views
Recall/Precision Metrics on Azure AutoML seem to be oriented to majority class, and I'm trying to focus on minority class
I am running some experiments in Azure using AutoML. My problem is a binary classification one, with highly imbalanced classes (basically trying to predict what factors make a deal "WON" ...
- 11
1
vote
0
answers
52
views
How to interpret the confusion matrix and compare the result of features extraction with LBP and Haralick
I'm begginer in deep learning so I tried to execute a code of liveness face detection from github in this link :https://github.com/imironica/liveness , so when I tried to run features extraction with ...
1
vote
0
answers
1k
views
Calculate the number of TP, FP, FN for the object detection task with many classes
I am trying to count the number of True Positives (TP), False Positives (FP), and False Negatives (FN) for object detection task with two classes. I assumed that:
TP - is the detection with ...
- 111
1
vote
0
answers
150
views
Generating a Confusion Matrix from a Seaborn Heatmap
Is there a way I can reverse engineer a Seaborn heatmap saved as .png? I want to get the array of values out of it. Does the library provide a "load-from-image" facility, or is there any sta
1
vote
0
answers
135
views
Is this analysis good or not?
I am doing a project in plant pest detection using CNN. There are four classes each having about 1000 images.I have use alexnet architecture for training. I think confusion matrix is not correct. What ...
- 111
1
vote
0
answers
17
views
Compute an ROC for a hybrid model where only one of the model components computes class probabilities
I've created a hybrid model by taking an existing decision engine (TRUE/FALSE output) and supplementing it with a random forest ...
- 114
1
vote
0
answers
3k
views
Can tuning individual precision and recall classification thresholds improve deep learning models?
I learned that Keras doesn't have a built-in way to set a threshold for precision and accuracy when building a classifier.
Courtesy of a solution here, I wanted to see what would happen when I fit a ...
- 477
1
vote
0
answers
48
views
Trying to come up with a feature to improve emotion classifier based on facial movement using facial landmarks
I managed to create an emotion recognition system that uses dense optical flow on each entire frame. While the accuracy range is within 80-90% with cross-validation, I am aiming to improve the ...
- 171
0
votes
0
answers
10
views
Finding Accuracy, Recall, Precision, and F1 from Matlab Confusion Matrix
I'm working on a project to find the highest accuracy between KNN and a Decision Tree for Classification using Matlab.
How to calculate the Accuracy, Recall, Precision, and F1 from the output below? ...
- 1
0
votes
0
answers
10
views
warning 'newdata' had X row but variables found have Y rows
Linear Discriminant Analysis (LDA)+logistic regression model
lda_model <- lda(train_labels ~ Sepal.Length + Sepal.Width + Petal.Length + Petal.Width, data = train_data)
LDA scores for the training ...
0
votes
1
answer
281
views
How many Non-frauds would be blocked to stop one Fraud based on the given confusion matrix?
One of the questions in a recent online test that I couldn't answer is below(I couldn't copy paste exact question, so this one is totally from memory. Kindly excuse in case of poor wording.)
We have a ...
- 197
0
votes
0
answers
12
views
One class confusion matrix notation for model evaluation
A one class classification set-up for a set of rules acting as a model, where
each input is a whole dataset
model makes some decision within the dataset for each entry
output is decisions made for ...
- 101
0
votes
1
answer
52
views
why my accuracy and recall become higher in testing than training. How to interpret
Why in hidden layer 2 and 3 in neural networks scratch, the accuracy and recall I got low, but in testing the accuracy and recall become higher. In hidden layer 4 it's get weird when sampling strategy ...
- 1
0
votes
0
answers
728
views
How does the background class work in object detection?
I am using YOLOv5 for object detection.
I understand that any labelled classes that are not predicted, that is, false negatives (FN) shows up as background. But how are the false positive (FP) being ...
0
votes
0
answers
111
views
High Recall and Low Precision for Binary CNN model
I was training a CNN model for binary classification. The training and validation accuracy seemed good. However, the precision is low and the recall is high (High false positive).
...
0
votes
0
answers
271
views
how to reduce overfitting and improve confusion matrix
I am trying to apply the following model on my data
which is consists of (4030 samples as 5 classes) each sample is MFCC features which is extracted from an audio clip consisting of (20 second)
and I ...
- 37
0
votes
0
answers
11
views
0
votes
0
answers
31
views
Logistic Regression test accuracy vs deployment
I am working on a problem where I make some weekly predictions. I gathered the data myself and did some pre-processing steps and I end up with 6 features. I split the dataset 60-20-20 in train, ...
0
votes
1
answer
47
views
Discrepancy between cross-validation and un-seen data predictions
I am facing an issue with an imbalanced dataset. The dataset contains 20% targets and 80% non-targets. I am expecting a confusion matrix below when I give un-seen data to the trained model.
...
0
votes
0
answers
86
views
Can you use a Confusion Matrix for a image detection problem?
I have read the classic examples of using a Confusion Matrix for a classification problem. ("Does a patient have cancer, or not?)
The ML system I am working with is for detecting objects in an ...
- 101
0
votes
0
answers
2k
views
How to track loss and accuracy in PyTorch?
I have made model and it is working fine for the MNIST dataset but further in the assignment it says to track loss and accuracy of the model, which I do not know how to do it. I have also written some ...
- 11
0
votes
1
answer
343
views
Unable to generate confusion matrix
I am using keras flow from directory for image segmentation. Following are my codes
...
- 23
0
votes
1
answer
1k
views
Weighted accuracy, sensitivity and specificity
I have a confusion matrix
TN= 27 FP=20
FN =11 TP=6
I want to calculate the weighted average for accuracy, sensitivity and specificity. I know the equation but unsure how to do the weighted averages.
0
votes
0
answers
238
views
How do I aggregate cross-validation results for per-sample insights?
I'm trying to do feature engineering for point cloud data with three classes, and after having finished implementing the most obvious and simplest features with somewhat good results I'd like to use ...
- 101
0
votes
0
answers
105
views
Calculating Uncertainty for categorical predictions
I am wondering what is the best way to calculate the uncertainty for my categorical predictions. I have created a model that predicts what rating a movie is getting based on certain keywords and the ...
- 1
0
votes
0
answers
36
views
Formulate Confusion Matrix from Precision Score
I have the precision scores from 5 classes. Is it possible to create the confusion matrix from that scores. While running the code, I only saved those precision values by mistake. So now I want to ...
0
votes
0
answers
757
views
Plotting scikit-learn confusion matrix returns no values in the last class
I am attempting to create a confusion matrix using Scikit-Learn for a multiclass classification CNN, and it works well except for the fact that it does not provide ...
- 23
0
votes
0
answers
167
views
How to plot a wordCloud for essay text from a confusion matrix false positive rate count?
I have an essay of text(BOW) and I have modelled it using let's say any model and plotted the confusion matrix and that I have got FPR, I need to plot a word cloud which shows the words due to which ...
- 101
-1
votes
1
answer
30
views
Printing the tweets that were incorrectly predicted after applying a machine learning classifier
I applied the random forest classifier to my csv file to classify the tweets as spam or not spam and after an accuracy of 93%, when I printed the confusion matrix I got
[[1068 105]
[ 65 1262]].
Now ...
- 23