Variational autoencoders

Variational autoencoders (VAEs) are generative models that combine the concepts of autoencoders and variational inference. They are neural network-based models that can learn a latent representation or code for input data, enabling them to generate new data samples similar to the training data.

Key components of variational autoencoders (VAEs)

  1. Encoder: The encoder network takes input data and maps it to a latent space representation. It learns to encode the input into a distribution over latent variables rather than a single point. This distribution is typically modeled as a multivariate Gaussian, with mean and variance parameters.
  2. Latent space: The latent space represents a lower-dimensional space where the data is encoded. It captures the essential features or representations of the input data. By sampling from the learned distribution in the latent space, new data points can be generated.
  3. Decoder: The decoder network takes a sample from the latent space and reconstructs the original input data. It maps the latent variables back to the input space, aiming to reconstruct the input as accurately as possible.
  4. Loss function: VAEs use a loss function that combines a reconstruction loss and a regularization term. The reconstruction loss measures the similarity between the reconstructed output and the original input, encouraging the model to accurately reconstruct the data. The regularization term, often based on the Kullback-Leibler (KL) divergence, encourages the learned latent space to follow a specific prior distribution (typically a standard Gaussian distribution).

Variational autoencoders (VAEs) – Applications

During training, VAEs aim to minimize the overall loss, which encourages the model to learn a compact and continuous representation in the latent space while being able to generate realistic samples.

The latent space representation in VAEs allows for various applications, including:

  1. Data generation: Once trained, VAEs can generate new samples by sampling from the learned latent space. By sampling different points and decoding them using the decoder network, VAEs can create new data points that resemble the original training data.
  2. Data imputation: VAEs can be used to fill in missing or corrupted parts of input data. By encoding the available information, modifying the latent variables, and decoding the modified latent representation, VAEs can generate plausible completions or imputations.
  3. Anomaly detection: VAEs can identify anomalous or out-of-distribution data by measuring the reconstruction error. Unusual or unseen data points tend to have higher reconstruction errors, indicating a deviation from the learned data distribution.
  4. Representation learning: VAEs learn a meaningful and structured latent representation of the input data. This latent space can be used as a compact and informative representation for downstream tasks like clustering, classification, or visualization.

VAEs have gained significant attention in the field of generative modeling and unsupervised learning due to their ability to learn meaningful latent representations and generate diverse samples. However, training VAEs can be challenging, requiring careful hyperparameter tuning and balancing of the reconstruction and regularization terms to achieve desirable results.


Just in

Tembo raises $14M

Cincinnati, Ohio-based Tembo, a Postgres managed service provider, has raised $14 million in a Series A funding round.

Raspberry Pi is now a public company — TC

Raspberry Pi priced its IPO on the London Stock Exchange on Tuesday morning at £2.80 per share, valuing it at £542 million, or $690 million at today’s exchange rate, writes Romain Dillet. 

AlphaSense raises $650M

AlphaSense, a market intelligence and search platform, has raised $650 million in funding, co-led by Viking Global Investors and BDT & MSD Partners.

Elon Musk’s xAI raises $6B to take on OpenAI — VentureBeat

Confirming reports from April, the series B investment comes from the participation of multiple known venture capital firms and investors, including Valor Equity Partners, Vy Capital, Andreessen Horowitz (A16z), Sequoia Capital, Fidelity Management & Research Company, Prince Alwaleed Bin Talal and Kingdom Holding, writes Shubham Sharma. 

Capgemini partners with DARPA to explore quantum computing for carbon capture

Capgemini Government Solutions has launched a new initiative with the Defense Advanced Research Projects Agency (DARPA) to investigate quantum computing's potential in carbon capture.