Deep Structured Latent Variable Models • Specify structure, but interpretable structure is often discrete e.g. POS tags, dependency parse trees
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Examples of Deep Latent Variable Models
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A probabilistic perspective on Variational Auto-Encoder
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What is Our Loss Function?
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Practice
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Variational Inference • Variational inference approximates the true posterior poll with a family of distributions
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Variational Inference • Variational inference approximates the true posterior polar with a family of distributions
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Variational Auto-Encoders
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Variational Autoencoders
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Learning VAE
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Problem! Sampling Breaks Backprop
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Solution: Re-parameterization Trick
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Difficulties in Training . Of the two components in the VAE objective, the KL divergence term is much easier to learn
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Solution 3
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Weaken the Decoder
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Discrete Latent Variables?
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Method 1: Enumeration
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Solution 4
Description:
Explore models with latent random variables in this comprehensive lecture from CMU's Neural Networks for NLP course. Delve into the distinctions between generative and discriminative models, as well as deterministic and random variables. Examine Variational Autoencoders (VAEs) in depth, including their structure, learning process, and challenges in training. Learn techniques for handling discrete latent variables and discover practical applications of VAEs in natural language processing. Gain insights into deep structured latent variable models and their importance in specifying interpretable structures like POS tags and dependency parse trees. Understand the probabilistic perspective on VAEs, explore variational inference methods, and study solutions to common training difficulties such as the re-parameterization trick and weakening the decoder.
Neural Nets for NLP - Models with Latent Random Variables