<p>I don't know much about boosting, but I accidentally noticed that we have the following boosting-related tags:</p>

<ul>
<li><a href="https://stats.stackexchange.com/questions/tagged/boosting" class="post-tag" title="show questions tagged &#39;boosting&#39;" rel="tag">boosting</a> × 311</li>
<li><a href="https://stats.stackexchange.com/questions/tagged/gbm" class="post-tag" title="show questions tagged &#39;gbm&#39;" rel="tag">gbm</a> × 179</li>
<li><a href="https://stats.stackexchange.com/questions/tagged/gradient-boosted-trees" class="post-tag" title="show questions tagged &#39;gradient-boosted-trees&#39;" rel="tag">gradient-boosted-trees</a> × 28</li>
</ul>

<p>The problem is that boosting (<a href="https://en.wikipedia.org/wiki/Gradient_boosting" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/Gradient_boosting</a>) is almost always used with decision trees, so [boosting] is almost exclusively about [gradient-boosted-trees]. Also, "GBM" stands for "gradient boosted machine" which was in the title of Friedman's <a href="https://scholar.google.de/scholar?q=gradient+boosted+machine" rel="nofollow noreferrer">famous 1999 paper</a>... where he introduced boosted trees! So it's all the same thing.</p>

<p><strong>Therefore, I think [gradient-boosted-trees] and [gbm] should become synonyms of [boosting].</strong> This combined tag would have <a href="https://stats.stackexchange.com/questions/tagged/boosting+or+gradient-boosted-trees+or+gbm">486 threads</a>. This seems to me to be a pretty clear-cut case.</p>

<p>In addition, we could consider merging the following tags:</p>

<ul>
<li><a href="https://stats.stackexchange.com/questions/tagged/xgboost" class="post-tag" title="show questions tagged &#39;xgboost&#39;" rel="tag">xgboost</a> × 122</li>
<li><a href="https://stats.stackexchange.com/questions/tagged/adaboost" class="post-tag" title="show questions tagged &#39;adaboost&#39;" rel="tag">adaboost</a> × 59</li>
<li><a href="https://stats.stackexchange.com/questions/tagged/gamboost" class="post-tag" title="show questions tagged &#39;gamboost&#39;" rel="tag">gamboost</a> × 5</li>
<li><a href="https://stats.stackexchange.com/questions/tagged/gmmboost" class="post-tag" title="show questions tagged &#39;gmmboost&#39;" rel="tag">gmmboost</a> × 1</li>
</ul>

<p>into [boosting] as well. These tags are not that large, are clear subsets of [boosting], and whoever is using boosting in practice is most likely (?) using either <code>xgboost</code> or <code>adaboost</code> anyway. If we merge all the above-listed tags into [boosting], then it would have <a href="https://stats.stackexchange.com/questions/tagged/boosting+or+xgboost+or+adaboost+or+gradient-boosted-trees+or+gamboost+or+gmmboost+or+gbm">613 threads</a>. I am making this second suggestion because I generally prefer larger tags, but I don't have much of an informed opinion here.</p>
