SheffieldML / SheffieldML/GPy

how can I use the hmc method to approximate the non gaussian likelihood, thank you

Open
#554 6 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Dominant language
Python
Stars
2.2k
Forks
570
PR merge metrics
No merged PRs in 30d

Description

I set the Possion distribution pdf as my GP likelihood, and want to use hmc method to infer its parameter. Here is my code as follows:

poisson_likelihood = GPy.likelihoods.Poisson()
kernel = GPy.kern.RBF(input_dim, variance=1.0, lengthscale=1.0)
hmc_inf= GPy.inference.mcmc.HMC()
m = GPy.core.GP(X=train_X_scaled, Y=train_Y_dl_total_scaled, likelihood=poisson_likelihood, inference_method=hmc_inf, kernel= kernel)

the error shows:

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-97-6f996d532af2> in <module>()
      3 poisson_likelihood = GPy.likelihoods.Poisson()
      4 kernel = GPy.kern.RBF(input_dim, variance=1.0, lengthscale=1.0)
----> 5 hmc_inf= GPy.inference.mcmc.HMC()
      6 m = GPy.core.GP(X=train_X_scaled, Y=train_Y_dl_total_scaled, likelihood=poisson_likelihood, inference_method=hmc_inf, kernel= kernel)
      7 

TypeError: __init__() missing 1 required positional argument: 'model'

So I want to know is there anyway that I can use the hmc to infer the parameters of an arbitrary likelihood? Thank you for your help!!!

Contributor guide

No contributing guide indexed for this repository

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start with GPy.inference.mcmc.HMC and inspect how its required model argument is used. Then review the GP construction and Poisson likelihood integration to determine whether HMC supports this case or what usage guidance is missing. Done means documenting the supported workflow and limitations for arbitrary likelihoods.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
machine-learning
Issue type
Documentation
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
20/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.