<p>If this is a strictly R programming/implementation question, it should go to SO. If this is a true statistics question, then an R package is just an implementation of the method, and one can often find alternative implementations in Stata, SAS, Matlab, or even (God forbid) Excel. So instead of <code>cv.glm</code> tag in the second type B question, it should have been the methods <code>cross-validation</code> tag. Any of the <code>*lme*</code> questions are actually <code>mixed-model</code> questions, etc.</p>

<p>On a number of occasions, I wrote in the tag excerpt something like "this tag is too generic, please use <code>this</code> for this, and <code>that</code> for that" (see, e.g., <code>multilevel</code> and <code>gmm</code> tags... I think the latter was actually killed, which isn't right, and should still be sitting around as a redirect). May be it is time to do something like this with <code>r</code>: officially declare R to be the default statistical package to ask questions about and give examples in, discourage the use of the <code>r</code> tag, and tell the users to use a tag like <code>learning-r</code> for the second question in A and the first question in B. Some other tags may need to be devised for "valid" R questions that CV rather than SO should handle, e.g., <code>compare-stat-packages</code> for tag combos like <a href="https://stats.stackexchange.com/questions/tagged/r+sas">https://stats.stackexchange.com/questions/tagged/r+sas</a> or <a href="https://stats.stackexchange.com/questions/tagged/r+stata">https://stats.stackexchange.com/questions/tagged/r+stata</a>.</p>
