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What is the Difference Between Test and Validation Datasets?

– Training set: A set of examples used for learning, that is to fit the parameters of the classifier.

– Validation set: A set of examples used to tune the parameters of a classifier, for example to choose the number of hidden units in a neural network.

– Test set: A set of examples used only to assess the performance of a fully-specified classifier.

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Causality in machine learning

Given recent advances and interest in machine learning, those of us with traditional statistical training have had occasion to ponder the similarities and differences between the fields. Many of the distinctions are due to culture and tooling, but there are also differences in thinking which run deeper. Take, for instance, how each field views the provenance of the training data when building predictive models. For most of ML, the training data is a given, often presumed to be representative of the data against which the prediction model will be deployed, but not much else. With a few notable exceptions, ML abstracts away from the data generating mechanism, and hence sees the data as raw material from which predictions are to be extracted. Indeed, machine learning generally lacks the vocabulary to capture the distinction between observational data and randomized data that statistics finds crucial. To contrast machine learning with statistics is not the object of this post (we can do such a post if there is sufficient interest). Rather, the focus of this post is on combining observational data with randomized data in model training, especially in a machine learning setting. The method we describe is applicable to prediction systems employed to make decisions when choosing between uncertain alternatives.

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Neural Network Embeddings Explained – Towards Data Science

Applications of neural networks have expanded significantly in recent years from image segmentation to natural language processing to time-series forecasting. One notably successful use of deep learning is embedding, a method used to represent discrete variables as continuous vectors. This technique has found practical applications with word embeddings for machine translation and entity embeddings for categorical variables.

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farizrahman4u/seq2seq: Sequence to Sequence Learning with Keras

Seq2Seq contains modular and reusable layers that you can use to build your own seq2seq models as well as built-in models that work out of the box. Seq2Seq models can be compiled as they are or added as layers to a bigger model. Every Seq2Seq model has 2 primary layers : the encoder and the decoder. Generally, the encoder encodes the input sequence to an internal representation called ‘context vector’ which is used by the decoder to generate the output sequence.

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