tensorflow / probability

Probabilistic reasoning and statistical analysis in TensorFlow
https://www.tensorflow.org/probability/
Apache License 2.0
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LinearGaussianStateSpaceModel with multivariate masking #311

Open mwong38 opened 5 years ago

mwong38 commented 5 years ago

Is it possible to allow mask (in forward_filter, log_prob, etc) to be multivariate i.e. with dimensions[num_timesteps, observation_size]rather than just[num_timesteps]`? That will allow missing observations within individual variables per time step and will be very helpful. I believe most of the current logic should work with minimal change.

davmre commented 5 years ago

Hi Michael, it's certainly possible, though I think the new logic isn't totally trivial. Instead of just doing an update vs not doing an update, I think you'd need to modify the observation model -- essentially project the observation matrix, noise mean and cov into the space of just the unmasked dimensions -- and do a partial update from just those dimensions.

Multivariate masking isn't on our immediate roadmap, but we're certainly happy to review pull requests!