<p>I've noticed that a specific user has engaged in a campaign to add the tag <a href="https://stats.stackexchange.com/questions/tagged/machine-learning" class="post-tag" title="show questions tagged &#39;machine-learning&#39;" rel="tag">machine-learning</a> to a number of posts that do not mention machine learning, particularly posts about <a href="https://stats.stackexchange.com/questions/tagged/neural-networks" class="post-tag" title="show questions tagged &#39;neural-networks&#39;" rel="tag">neural-networks</a>.</p>

<p>I don't think these edits are useful. I also think that there are a couple of overlapping problems which are at work.</p>

<ol>
<li><p>The tag description for <a href="https://stats.stackexchange.com/questions/tagged/machine-learning" class="post-tag" title="show questions tagged &#39;machine-learning&#39;" rel="tag">machine-learning</a> is </p>

<blockquote>
  <p>Methods and principles of building 'computer systems that try to automatically improve with experience.'</p>
</blockquote>

<p>which is not <strong>obviously</strong> distinct from a <a href="https://stats.stackexchange.com/questions/tagged/neural-network" class="post-tag" title="show questions tagged &#39;neural-network&#39;" rel="tag">neural-network</a>. A novice in the field could reasonably think of the two terms as interchangeable, and I think that is exactly what's caused this user to start adding the <a href="https://stats.stackexchange.com/questions/tagged/machine-learning" class="post-tag" title="show questions tagged &#39;machine-learning&#39;" rel="tag">machine-learning</a> tag to <a href="https://stats.stackexchange.com/questions/tagged/neural-networks" class="post-tag" title="show questions tagged &#39;neural-networks&#39;" rel="tag">neural-networks</a> questions.</p>

<p>In my view, "machine learning" is the popular name for what Hastie et al call "statistical learning" in their landmark book <em>Elements of Statistical Learning</em>. Statistical learning, and its synonym "machine learning," both include neural networks as a special case.</p></li>
<li><p>I think the <a href="https://stats.stackexchange.com/questions/tagged/machine-learning" class="post-tag" title="show questions tagged &#39;machine-learning&#39;" rel="tag">machine-learning</a> description sounds a lot more like <a href="https://stats.stackexchange.com/questions/tagged/reinforcement-learning" class="post-tag" title="show questions tagged &#39;reinforcement-learning&#39;" rel="tag">reinforcement-learning</a>, which strives to create self-teaching algorithms to learn from experience, than it describes statistical learning.</p></li>
<li><p>I don't think it makes sense to apply a more general tag when a more specific tag is sufficient. <em>Elements of Statistical Learning</em> discusses cubic splines, and you can use splines in a machine learning project, but I wouldn't add the <a href="https://stats.stackexchange.com/questions/tagged/machine-learning" class="post-tag" title="show questions tagged &#39;machine-learning&#39;" rel="tag">machine-learning</a> tag to a question <em>solely</em> about <a href="https://stats.stackexchange.com/questions/tagged/splines" class="post-tag" title="show questions tagged &#39;splines&#39;" rel="tag">splines</a>.</p>

<p>On the other hand, the <a href="https://stats.stackexchange.com/questions/tagged/machine-learning" class="post-tag" title="show questions tagged &#39;machine-learning&#39;" rel="tag">machine-learning</a> tag is useful if you're asking a soft question, or a question about the general field. For example, the question "Why is cross-validation important in machine learning?" does not need to be concerned with random forest or SVMs or neural networks in particular. Likewise, "What is overfitting and how do you measure it?" is a question generally about statistical learning and not any specific method.</p></li>
<li><p>The edit queue doesn't seem to be working. In my view, these edits add irrelevant tags, which is a reason to reject; however a number of these edits were approved anyway.</p></li>
<li><p>The overall usage of the <a href="https://stats.stackexchange.com/questions/tagged/machine-learning" class="post-tag" title="show questions tagged &#39;machine-learning&#39;" rel="tag">machine-learning</a> tag needs some attention. The usage varies from <a href="https://stats.stackexchange.com/questions/tagged/reinforcement-learning" class="post-tag" title="show questions tagged &#39;reinforcement-learning&#39;" rel="tag">reinforcement-learning</a> to <a href="https://stats.stackexchange.com/questions/tagged/neural-networks" class="post-tag" title="show questions tagged &#39;neural-networks&#39;" rel="tag">neural-networks</a> to general statistics questions. I don't know what the best way is to make this tag useful; a large part of the problem is machine learning has become a marketing buzzword that means, essentially, "One of our employees did statistics on a computer." I think it would be technically correct but quixotic to force the usage of "statistical learning" in the place of "machine learning." Moreover, such a move might give people the impression that "machine learning" is not on-topic here, which is something we already have enough trouble with.</p></li>
</ol>

<p>My questions for the community are</p>

<p><strong>A.</strong> What, if anything, needs to be done to improve the <em>description</em> of the <a href="https://stats.stackexchange.com/questions/tagged/machine-learning" class="post-tag" title="show questions tagged &#39;machine-learning&#39;" rel="tag">machine-learning</a> tag?</p>

<p><strong>B.</strong> What should be done to improve the <em>usage</em> of the <a href="https://stats.stackexchange.com/questions/tagged/machine-learning" class="post-tag" title="show questions tagged &#39;machine-learning&#39;" rel="tag">machine-learning</a> tag?</p>

<p><strong>C.</strong> How can we best educate reviewers to thoughtfully consider edits which propose adding irrelevant tags?</p>
