<p>You can easily see that many of our questions are not mathematical and include questions about things like how to define variables (<em>how many categories should I use?</em> is a reasonably commonly asked question). Some of these questions - if appropriately framed - will probably be within the scope of our topic coverage, but for a number of those questions the chances of an answer that will be anything but vague may not be high -- in particular questions similar to "how many categories should I use" may be answered with anything from "don't split into categories" to "we can't answer that on the basis of this information" (which means some may eventually be closed as too broad or unclear without a lot more details), depending on whether it makes more sense to split at all.</p>

<p>The solution to that second kind of issue (how to categorize things given that you must do so) -- once you've identified the details enough to make it answerable at all -- will then probably already be about as obvious to you as to anyone else. </p>

<p>The more information you can give about your aims, specific questions of interest, preferences, intended audience, specific subject-area knowledge about the variables -- and so on (though preferably expressed succinctly) the more likely someone may be able to say something helpful. We generally can't just say "oh, use <em>four</em> categories". However, for many things, few categories will often be worse than many, unless other constraints force fewer on you.</p>

<p>So broadly, yes you can ask such questions, but answers that are simultaneously quick and useful may not be typical</p>

<p>As a specific example "<em>"Is it correct to include people who left high school early to complete a university degree in the definition of 'High School Dropout'</em>", "correctness" of your choice of what's included in a category is not a statistical issue, so that would need to be reframed to be on topic. (We <em>can</em> often answer questions about potential consequences of mixing two apparently quite distinct groups on your inferences, for example.)</p>

<p>Outside of such directly statistical considerations, whether it makes sense to include it or to do any of several other things really depends on what questions you want to answer, the way in which you want to answer them, the tolerance of your intended audience for doing so, and so on. This is not information we can give you (we don't tell you what you want to study and we're not typically experts in your application area), but instead you would need to supply any such information.</p>
