Issue/761 efficiency tuning

[mitzimorris]

Submission Checklist

• [x] Builds locally
• [ ] New functions marked with <<{ since VERSION }>>
• [x] Declare copyright holder and open-source license: see below

Summary

see #761

Copyright and Licensing

Please list the copyright holder for the work you are submitting (this will be you or your assignee, such as a university or company): Columbia University

By submitting this pull request, the copyright holder is agreeing to license the submitted work under the following licenses:

• Code: BSD 3-clause (https://opensource.org/licenses/BSD-3-Clause)
• Documentation: CC BY-ND 4.0 (https://creativecommons.org/licenses/by-nd/4.0/)

[mitzimorris]

multivariate normal prior on alpha_std and beta_std

hi @rtrangucci - please clarify. in section "Standardizing predictors" - should the model code be changed? or just add this clarification?

[mitzimorris]

made changes, ready for review / re-review. @rtrangucci @bob-carpenter

[mitzimorris]

ready for re-review.

[rtrangucci]

multivariate normal prior on alpha_std and beta_std

hi @rtrangucci - please clarify. in section "Standardizing predictors" - should the model code be changed? or just add this clarification?

I would just add this for clarification because it's not intuitive that independent priors on $(\alpha, \beta)$ maps to a multivariate normal prior on $(\alpha^\prime, \beta^\prime)$ (at least not intuitive to me).

[mitzimorris]

thanks @rtrangucci - changes made.

regarding clarification re independent priors mapping to multivariate prior - it seems a little off topic.

OK, didn't understand this comment before - will try to address.

[mitzimorris]

@rtrangucci ready for re-review.

[rtrangucci]

Looks good!

[rtrangucci]

@mitzimorris Do I need to merge, or can you?

[mitzimorris]

thanks @rtrangucci - I can merge