stan-dev / stan-dev/rstanarm

Add another argument(s) for R2 prior

Open
#428 0 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

feature
Dominant language
R
Stars
401
Forks
136
PR merge metrics
No merged PRs in 30d

Description

Summary:

stan_lm prior R2 can be used to set Beta(K/2, eta) prior on R^2. Value of eta is controlled
with arguments what and location. If K is large then this Beta prior is very informative. It would be useful to add another argument which would control the informativeness.

I'm not certain about the argument name, but maybe following @paul-buerkner and use par_ratio which would describe ratio of expected number of relevant predictors.

Alternatively there could also be direct Beta distribution arguments alpha and beta and the user would then think in terms of Beta distribution directly.

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 by locating the stan_lm implementation of the R2 prior and read how the existing what and location arguments determine eta. Decide whether the feature should expose a par_ratio-style control or direct Beta parameters, then define and validate the chosen interface and its effect on prior informativeness.

Written by the indexing model from the issue text.

Assessment

Tech stack
r
Domain
data
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.