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I have a small dataset (20 instances per 13 classes). The 13 classes are human users from their behavior features, I have to classify if an unseen behavior feature is of a user or not.

Data: These features are basically mouse events (x, y, timestamp) in a sequence upto 200 elements-long. And there is also an associated bi-gram key press time which has been binned into a range of 200 bins with 1 ms width. A user would have 20 events as [[[x, y, time]...], [0,0,0,..,1,2,0,3,..]]

Problem: I have tried several statistical techniques, and of all, SVMs with linear kernel are giving the best result, but the result is far from decent. I have trained an SVM per user, and the average false acceptance rate is only 25%, with false rejection rate around 7%.

I am not a seasoned data scientist and just breaking into the field, what are the ways I can go around improving the solution? (In terms of algorithms, technqiues to try) I have already tried K-means, Distance-based, random forests. Is my data too small to even capture the hypothesis? Can methods like one-shot learning be applied.

Background: I tried to create a heatmap of the mouse-movements, and there does seem to be patterns tied to users. Here are two plots for different users.

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Here's a sample of the dataset

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As you mention, your dataset is quite small. Personally I think that it is too small for exploring the implementation of a model, but trying a few things wouldn't hurt.

There is a python package called smote which helps in oversampling/undersampling. This method is mainly used when dealing with imbalanced datasets , but you could try implementing it and creating new artificial entries. You can check out the docs here: SMOTE and the paper, on which it is based here: SMOTE paper . Please bare in mind that by following this method and creating artificial instances you might alter the dataset so much that the initial information is lost thus resulting to a model which will not address your task properly. Also, a synthetic dataset means that you will probably have to deal with overfitting.

Moreover, since you have tried multiple models, you could combine them (model ensembling) and create a multiple model voting system. Sklearn has a method for this from the ensemble class Voting Classifier

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