Covariance Prediction via Convex Optimization
- URL: http://arxiv.org/abs/2101.12416v1
- Date: Fri, 29 Jan 2021 06:06:58 GMT
- Title: Covariance Prediction via Convex Optimization
- Authors: Shane Barratt and Stephen Boyd
- Abstract summary: We describe a covariance predictor that has the form of a generalized linear model, i.e., an affine function of the features followed by an inverse link function.
The log-likelihood is a concave function of the predictor parameters, so fitting the predictor involves convex optimization.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We consider the problem of predicting the covariance of a zero mean Gaussian
vector, based on another feature vector. We describe a covariance predictor
that has the form of a generalized linear model, i.e., an affine function of
the features followed by an inverse link function that maps vectors to
symmetric positive definite matrices. The log-likelihood is a concave function
of the predictor parameters, so fitting the predictor involves convex
optimization. Such predictors can be combined with others, or recursively
applied to improve performance.
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