EDIT October 2020: Thank you all for having helped me understanding this model in the last 5 years! I recently published a book chapter explaining what I understood about siamese neural networks and reporting all the possible applications of this model that I found in the scientific literature. You can find it here: "Siamese neural networks: an overview". I hope you can find it useful: if this book chapter exists now, it's also because of the wonderful help you guys provided to be back then. Thanks again!
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