Gaussian Process Latent Factor Regression for Low-Data, High-Dimensional Output Problems
Summary
Gaussian Process Latent Factor Regression (GPLFR) is a new probabilistic model designed for regression tasks with low training data and high-dimensional outputs, common in scientific fields. Unlike traditional compress-then-predict methods like PCA-GP, GPLFR jointly learns latent representations and output reconstruction, biasing the representation towards predictability from inputs. This approach addresses the issue where PCA-GP's basis is optimized for reconstruction rather than prediction, especially when structured, unpredictable variation is present. Experiments show GPLFR achieves the same error as PCA-GP with approximately 4× fewer training data on a synthetic benchmark. It also demonstrates superior sample and representation efficiency in biomedical optics emulation and strongly outperforms alternatives in emulating global climate models for rocky exoplanets, handling D_y ≈ 3 × 10^4 output dimensions.
Key takeaway
For Research Scientists or Machine Learning Engineers developing emulators for complex scientific simulations with limited data and high-dimensional outputs, GPLFR offers a significant advantage over traditional PCA-GP pipelines. You should consider implementing GPLFR to improve sample efficiency and prediction accuracy, especially when dealing with structured output noise. Be prepared for a more challenging optimization landscape, which can be mitigated using likelihood tempering and latent noise regularization.
Key insights
GPLFR couples representation learning and regression to prioritize predictable structure in high-dimensional, low-data output problems.
Principles
- Jointly optimize latent representation and regression.
- Bias representation towards input-predictable structure.
- Analytically marginalize decoder weights.
Method
GPLFR represents outputs as a linear-Gaussian decoding of a low-dimensional latent state from a GP prior. It analytically marginalizes decoder weights, coupling compression and prediction in a single objective. Optimization uses MAP estimation with Adam, stabilized by likelihood tempering and latent noise.
In practice
- Use GPLFR for high-dimensional scientific emulation.
- Apply likelihood tempering for decoder misspecification.
- Consider PCA initialization for noiseless data.
Topics
- Gaussian Process Regression
- Latent Factor Models
- High-Dimensional Regression
- Exoplanet Climate Models
- Scientific Emulation
- Low-Data Learning
Code references
Best for: AI Scientist, Research Scientist, Machine Learning Engineer
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Editorial summary, takeaway, and curation by AIssential. Original article published by stat.ML updates on arXiv.org.