Create feature comparisons table

[luiarthur]

A features table will also be compiled for the various PPLs. These may include:

• support / workarounds for missing data, with MWE.

• support / workarounds for ragged arrays, with MWE.

• support / workarounds for inference of discrete parameters, with MWE

  • Nimble and Pyro supports direct inference on discrete parameters. The recommended workaround in other PPL's is marginalizing discrete parameters, but this is not always possible.

• support for automatic differentiation

• Customizability

  • e.g. For MCMC, using a custom (user-provided) implementation to update a subset of model parameters, and use default update mechanisms (Metropolis-within-Gibbs or HMC) for the other parameters.

• support for HMC, Metropolis-within-Gibbs, ADVI / BBVI, and auto-tuning for each PPL.

• [ ] The table below is an example of what the Feature Comparisons table could look like.

	Turing	STAN	Pyro	Nimble	TFP
Supports inference for discrete parameters	[ ] TODO	No (workaround)	Yes	Yes	No (workaround)
Supports missing data	[ ] TODO	[ ] TODO	[ ] TODO	Yes	No (workaround)
Supports AD	[ ] TODO	[ ] TODO	[ ] TODO	[ ] TODO	[ ] TODO
Supports customization of MCMC	[ ] TODO	[ ] TODO	[ ] TODO	[ ] TODO	[ ] TODO
Supports HMC	[ ] TODO	[ ] TODO	[ ] TODO	[ ] TODO	[ ] TODO
Supports NUTS	[ ] TODO	[ ] TODO	[ ] TODO	[ ] TODO	[ ] TODO
Supports ADVI	[ ] TODO	[ ] TODO	[ ] TODO	[ ] TODO	[ ] TODO
etc.	[ ] TODO	[ ] TODO	[ ] TODO	[ ] TODO	[ ] TODO