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My guess is that the data you provide does not have enough information to predict $a, b, c, d$ or $e$. Therefore, because $b$ is over-represented in the dataset, it will always predict $b$, because thats the safest bet. If you didn't know anything about the input or you if you wouldn't be able to extract any useful information from it, you would probably ...


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The performance of machine learning algorithms is not commonly evaluated with null hypothesis significance testing (NHST). Machine learning performance is evaluated with performance on a hold-out data (e.g., validation or test), regardless of the evaluation metric.


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If your dataset is too small, it won't apply to other new data easily. In this case, you should either: try to increase your training dataset Find new images and classify them to increase the training data size, the model will improve as you add new images, but this can be time consuming use transfer learning Find a model that someone else built on a ...


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It looks like the new data has a different distribution from the training data. It looks like the training data is just a single fruit, with white background, and the new image you've passed is a picture of bananas with blue background. The model has probably learned something like: if blue image, then blueberries, and for this reason it classifies the blue ...


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What you were told is a worst case scenario. With 5 labels, 20.01% is the lowest possible value that a model would need to choose one class over the other. If the probability for each of the 5 classes are almost equal then the probabilities for each would be approximately 20%. In this case, the model would be having trouble deciding which class is correct. ...


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This is called an open-class text classification problem, it's used in particular for some author identification problems. I don't have any recent pointers but from a quick search I found this article: https://www.aclweb.org/anthology/N16-1061.pdf In the field of author classification there is a similar problem called author verification, which can be ...


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Apart from your desired two classes, relabel all other classes as a third class and then train your model on a three class classification problem.


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You are talking about a multi label classification, which is a common type of problem. The most common choice of loss function is binary crossentropy There’s a tutorial here that might help: https://towardsdatascience.com/multi-label-image-classification-with-neural-network-keras-ddc1ab1afede


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I have also been pondering on this question and trialled loss function on this sort of problem. For these type of classification tasks, the loss function which seems most appropriate is Binary Cross Entropy Loss : https://towardsdatascience.com/understanding-binary-cross-entropy-log-loss-a-visual-explanation-a3ac6025181a


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Accuracy has a specific meaning classification - the data points with predicted labels must exactly match actual labels over the total number of data points. In order to calculate accuracy, you need the actual labels for each data point. If you do not have actual labels for a data point, those data points can not be used in the analysis.


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Here's my solution for sparse categorical crossentropy for a Keras model with multiple outputs in TF2. I think it looks fairly clean but it might be horrifically inefficient, idk. First create a dictionary where the key is the name set in the output Dense layers and the value is a 1D constant tensor. The value in index 0 of the tensor is the loss weight of ...


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