Gaussian Process for Noisy Inputs with Ordering Constraints
This addresses the challenge of noisy data in temporal applications like sea-level rise prediction, offering an incremental improvement over existing noisy input GP methods.
The paper tackles Gaussian Process regression with noise in both inputs and outputs by incorporating monotonic ordering constraints on latent inputs, resulting in improved predictive performance and reduced computational costs compared to state-of-the-art methods.
We study the Gaussian Process regression model in the context of training data with noise in both input and output. The presence of two sources of noise makes the task of learning accurate predictive models extremely challenging. However, in some instances additional constraints may be available that can reduce the uncertainty in the resulting predictive models. In particular, we consider the case of monotonically ordered latent input, which occurs in many application domains that deal with temporal data. We present a novel inference and learning approach based on non-parametric Gaussian variational approximation to learn the GP model while taking into account the new constraints. The resulting strategy allows one to gain access to posterior estimates of both the input and the output and results in improved predictive performance. We compare our proposed models to state-of-the-art Noisy Input Gaussian Process (NIGP) and other competing approaches on synthetic and real sea-level rise data. Experimental results suggest that the proposed approach consistently outperforms selected methods while, at the same time, reducing the computational costs of learning and inference.