<p>I think the decision to migrate my question reflects an over-zealous concern by the moderators for maintaining a strict separation from SO. Questions about software <strong><em>are</em></strong> appropriate on CV. The FAQ (I wrote the first version) includes "statistical and data-driven computing". Asking what package implements a specific procedure falls directly into that category. </p>

<p>Also, the question is <em>not</em> appropriate on SO because I wasn't asking a programming question.</p>

<p>I disagree with @gung that CV questions should only be asking about "a statistical (machine learning, etc.) concept / principle". That is clearly too restrictive according to the FAQ (or whatever it is now called at <a href="https://stats.stackexchange.com/tour">https://stats.stackexchange.com/tour</a>).</p>

<p>If it is inappropriate to ask a question about software on SO or CV, where should it be asked? I think it is reasonable to think that all (good) questions should have a home on the SE network, and so I do not agree that the question needs to be shunted off to one of the R lists.</p>

<p>I could have written the question differently as @gung has suggested, but then it would be a different question, and not the one I wanted answering. </p>

<p>So my view, for what it is worth, is that the question <em>is</em> a good fit for CV and does not need revising.</p>
