Questions tagged [multiclass-classification]
In machine learning, multiclass or multinomial classification is the problem of classifying instances into one of three or more classes (classifying instances into one of two classes is called binary classification).
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Classifying Images that Look Like Noise
I'm about to build a system that is supposed to evaluate images (900 x 150) like the following and classify it in to one of five categories:
image that looks like noise
In case you're wondering, they'...
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Why is my multi-task-learning model not working?
I'm writing Python code to predict fetal head circumference using regression and classification together in a single model.
The model will train to classify a fetal head image into a range (e.g., 50–...
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Linear SVM Hyperparameter Selection
I'm trying to train a linear SVM on the CIFAR-10 dataset and I obtained the results in the plot below for the hyper-parameter tuning (learning rate and regularization strength). It looks like the ...
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Why does the accuracy get stuck at a constant value when using Keras for multiclass singles-label classification problem?
I am trying to solve a multiclass classification problem using Keras. The current network looks as follows:
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Why my deep learning model (FCNN/ 1DCNN) fails to learn when training on medical dataset?
I am working on a project to predict the severity of the disease, Hemophilia using a deep learning model(FCNN or 1DCNN). I am working based on the information provided in this article: https://www....
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Approaches for multi-label classification with over 1,000,000 labels
I have billions of rows in some dataset and each row can be in any subset of about 1 million binary labels. So the number of overall classes would be $\sim 2^{1,000,000}$, if I were to think about it ...
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Multi-instance learning for time-spatio-dependent data
I am trying to use MIL approach from the paper Attention-based Deep Multiple Instance Learning on the data that is a frames of human pose images acquired on different angle on each timepoint (temporal ...
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How can a Regression based Neural Network learn class thresholds?
I understand that to solve multilabel classification problems, we can use the softmax activation function in the output layer of the neural network. The softmax function outputs probabilities of each ...
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Image classification problem with multiple right classes
I have a use case where the model needs to detect fabricdefects. There are 15+ different kinds of defects. In one image there can be multiple defects present. The straight forward solution for this ...
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Which algorithm for hierarchical and ordered classification? [closed]
I have developed the "Pyrates" application which is a serious game to learn programming in Python.
In each level of the game, you have to pick up a key and open a chest. To do this, you need ...
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Out of distribution detection (OOD) in the context of regression problems
I'm working in a regression setting to predict a scalar value $y$ from an input $\textbf{x} \in \mathbb{R}^D$ and I'm interested in understanding whenever my model is fed with something that it is ...
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1D Sequence Classification with self-supervised learning
I am working on a multi-class classification task on long one-dimensional sequences. The sequence length may vary in the range $[512, 30720]$, and there is one feature associated each time-step in the ...
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Multiclass Ensemble Methods with weak classifiers under 50%
Normally, when using an ensemble method, such as baggin or boosting, in binary classification, there is a reqauirment that each weak classifier have accuracy better than 50%.
In the multiclass ...
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Low accuracy and high loss in multi-class classification [closed]
I'm trying to classify images in 17 flowers dataset which consist of 1360 images of 17 classes (80 images per class); I have to use DNNs only therefore I made my model with the following settings:
<...
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Use soft-max post-training for a ReLU trained network?
For a project, I've trained multiple networks for multiclass classification all ending with a ReLU activation at the output.
Now the output logits are not probabilities.
Is it valid to get the ...
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How to label unsupervised data for deep learning multi-classification
I have unlabeled credit card transaction data that has the following columns:
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Multi-class classification but a single feature sometimes boils it down to a binary-classification
I have a three-class classification problem for a large dataset. Classes are 0, 1, and 2. There's a categorical variable in my feature vectors such that when a sample point has this variable positive, ...
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When to use Multi-class CNN vs. one-class CNN
I'm building an object detection model with convolutional neural networks (CNN) and I started to wonder when should one use either multi-class CNN or a single-class CNN. That is, if I'm making e.g. a ...
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How do I select the class weights for the loss function in the case of more than 2 classes?
I have a machine learning task where I would like to weight losses based on the frequency of the categorical values appearing in the data. The binary solution can be seen below, but I'd like to know ...
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Why would the "improvement" be the result of random initialization, and so why should we use multiple runs?
I got this feedback for my thesis paper.
The improvement shown in the results section could be the result of random initialization. There should be multiple runs with means and standard deviations.
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How to deal with images that do not contain any object of interest?
I'm currently working on an iOS App where I want to detect if there is a table, chair or bench in the current camera input.
My idea was to take the MobileNetV2 model and get it to classify these three ...
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What is the difference (if any) between semantic segmentation and multi-class, mutually exclusive classification?
Multi-class classification is simply assigning all data points into one of up to any finite number of mutually exclusive labels. I am new to the field(s) of AI/ML and I keep hearing people use the ...
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How to perform multi-class text classification with a dataset of 80 documents?
I have a training dataset of 80 text documents with an average number of characters in each document of 25000 and 210 unique tags.
How can I perform multi-class text classification with such a small ...
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Why do we use the softmax instead of no activation function?
Why do we use the softmax activation function on the last layer?
Suppose $i$ is the index that has the highest value (in the case when we don't use softmax at all). If we use softmax and take $i$th ...
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How do I calculate the probabilities of the BERT model prediction logits?
I might be getting this completely wrong, but please let me first try to explain what I need, and then what's wrong.
I have a classification task. The training data has 50 different labels. The ...
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Using one-class classification first to find anomalies then apply multi-class classification
I'm new to machine learning and trying to apply it for fault detection, an idea came to mind which is using only anomaly detection after which if the results after a while come up as positive, a multi-...
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Multi class text classification when having only one sample for classes
I have a dataset of texts, each text was identified with an ID number. I would like to do a prediction by finding the best match ID number for upcoming new texts. To use multi text classification, I ...
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When computing the ROC-AUC score for multi-class classification problems, when should we use One-vs-Rest and One-vs-One?
The sklearn's documentation of the method roc_auc_score states that the parameter multi_class can take the value ...
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Is Mask R-CNN suited to solve a multi-class classification problem where the classes are related?
I want to create a model to solve a multi-class classification problem.
Here are more details about my problem.
Every picture contains only one object
The background is very simple
All objects ...
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Is it possible to combine k-fold cross-validation and oversampling for a multi-class text classification task with imbalanced data?
I am dealing with an intent classification task on an Italian customer service data set.
I've more or less 1.5k sentences and 29 classes (imbalanced).
According to the literature, a good choice is to ...
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How can I prevent the CNN from classifying a new input into one of the existing labels (it was trained with) when the input has a new different label? [duplicate]
I'm trying to perform image classification with a CNN. In my case, the inputs are the covers of 9 books, so there are 9 labels. I am using TensorFlow's Keras.
If I pass a new input (that has a label ...
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What is the general procedure to use and train neural networks for multi-class classification?
I am very new to machine learning. I am following the course offered by Andrew Ng. I am very confused about how we train our neural network for multi-class classification.
Let's say we have $K$ ...
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How to implement an "unknown" class in multi-class classification with neural networks?
For example, I need to detect classes for MNIST data. But I want to have not 10 classes for digits, but also I want to have 11th class "not a digit", so that any letter, any other type of ...