<p>I suggest merging <a href="https://stats.stackexchange.com/questions/tagged/arch" class="post-tag" title="show questions tagged &#39;arch&#39;" rel="tag">arch</a> and <a href="https://stats.stackexchange.com/questions/tagged/garch" class="post-tag" title="show questions tagged &#39;garch&#39;" rel="tag">garch</a> tags, or making <a href="https://stats.stackexchange.com/questions/tagged/arch" class="post-tag" title="show questions tagged &#39;arch&#39;" rel="tag">arch</a> a synonym of <a href="https://stats.stackexchange.com/questions/tagged/garch" class="post-tag" title="show questions tagged &#39;garch&#39;" rel="tag">garch</a> (I am not sure how I should formulate this correctly). </p>

<ul>
<li>I don't see sufficient conceptual difference between ARCH and GARCH models to maintain both tags. </li>
<li>GARCH is more general, so I suggest keeping <a href="https://stats.stackexchange.com/questions/tagged/garch" class="post-tag" title="show questions tagged &#39;garch&#39;" rel="tag">garch</a> as the tag name to remain. </li>
<li><a href="https://stats.stackexchange.com/questions/tagged/arch" class="post-tag" title="show questions tagged &#39;arch&#39;" rel="tag">arch</a> has 41 questions while <a href="https://stats.stackexchange.com/questions/tagged/garch" class="post-tag" title="show questions tagged &#39;garch&#39;" rel="tag">garch</a> has 292; only <strong>11</strong> questions are tagged with <a href="https://stats.stackexchange.com/questions/tagged/arch" class="post-tag" title="show questions tagged &#39;arch&#39;" rel="tag">arch</a> without <a href="https://stats.stackexchange.com/questions/tagged/garch" class="post-tag" title="show questions tagged &#39;garch&#39;" rel="tag">garch</a>. </li>
<li>I have checked the questions tagged <a href="https://stats.stackexchange.com/questions/tagged/arch" class="post-tag" title="show questions tagged &#39;arch&#39;" rel="tag">arch</a> without <a href="https://stats.stackexchange.com/questions/tagged/garch" class="post-tag" title="show questions tagged &#39;garch&#39;" rel="tag">garch</a> and I do not see that they would be sufficiently special to deserve a separate tag.</li>
</ul>

<p>If the community agrees (we will see), how can this be done? It would be nice to get rid of <a href="https://stats.stackexchange.com/questions/tagged/arch" class="post-tag" title="show questions tagged &#39;arch&#39;" rel="tag">arch</a> in a way that it would not reappear soon thereafter and there would not be a need to raise the question again.</p>

<p><strong>Edit:</strong> vote <a href="https://stats.meta.stackexchange.com/questions/1200/current-tag-synonym-candidates/4270#4270">here</a> in the thread for suggested synonyms.</p>
