[FR] Propose that prior choice recommendations goes into SUG

[spinkney]

I don't know if many people ever visit the wiki on the Stan github repo. The prior choice recommendations is https://github.com/stan-dev/stan/wiki/Prior-Choice-Recommendations.

@andrewgelman do you have any thoughts on adding this to the docs instead?

[bob-carpenter]

@spinkney: Can you be more specific? We'd like to avoid people working on issues, only to have someone on the stan-dev side say, "No, that's not what we were thinking." So we're trying to make issues more like feature specifications than a general wish list.

I see at least three options:

• shoveling the markdown into LaTeX as a new chapter minus all the bullet points
• doing the above, but actually filling out details rather than saying "use penalized complexity" with a pointer to a paper
• integrating the prior recommendations with the relevant model chapters (e.g., putting GP prior suggestions in the GP chapter)

The real issue is that it's not at all written like our user's guide, which tries to be friendly an step-by-step with Stan code. The markdown has very little math and pretty much zero Stan code. So the question is how much work is this going to be and what's the minimal thing that everyone would be happy with?