Fix dimensions of coefficient matrix

[mgrabovsky]

The dimension of the matrix beta of coefficients in multi-logit regression should be D × K in accord with the initial example, not K × D.

Submission Checklist

• Builds locally – couldn't get the build system to work
• Declare copyright holder and open-source license: see below

Summary

Copyright and Licensing

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Matěj Grabovský

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 4.0 (https://creativecommons.org/licenses/by/4.0/)

[bob-carpenter]

Thanks! There's one change request which is optional as it wasn't an issue introduced intros PR. Please let me know if I should merge or if it'd be OK to fix the definition of beta to be a declare-define.

[mgrabovsky]

Thanks for the review. I've made that one change you suggested.

[bob-carpenter]

Thanks.

The only problem now is that _main.Rmd was inadvertently included. That's a byproduct of bookdown building the docs and not something we want to include in the repo.

[mgrabovsky]

Sorry about that. (Perhaps it could be added to the gitignore to prevent such issues in the future?)

[bob-carpenter]

Looks good. Thanks.

[bob-carpenter]

Yes, I think it makes sense to add it to our gitignore. I created an issue: #398