<p><a href="https://en.wikipedia.org/wiki/Additive_smoothing" rel="nofollow noreferrer">Laplace smoothing</a> (also known as additive smoothing) is a very particular smoothing technique concerning <em>categorical</em> data. Laplace smoothing is almost always associated with a probability regularisation task and thus it does not immediately relate to "standard" smoothing techniques (eg. <a href="https://en.wikipedia.org/wiki/Kernel_smoother" rel="nofollow noreferrer">kernel smoothing</a>,   <a href="https://en.wikipedia.org/wiki/Smoothing_spline" rel="nofollow noreferrer">smoothing spline</a>, etc.) concerned with variations along a (usually linear) continuum. </p>

<p>I think it will be beneficial to have a separate <code>[laplace-smoothing]</code> tag. At first instance it seems that 25 to 30 questions might warrant the tag. I think it will make it easier for ML practitioners to recognise/filter relevant questions. Some questions that would affected are the following:</p>

<ol>
<li><a href="https://stats.stackexchange.com/questions/238822">Understanding Add-1/Laplace smoothing with bigrams</a>    </li>
<li><a href="https://stats.stackexchange.com/questions/83203">Laplace smoothing and Dirichlet prior</a></li>
<li><a href="https://stats.stackexchange.com/questions/272826">Laplace smoothing and naive bayes</a></li>
<li><a href="https://stats.stackexchange.com/questions/246952">Laplace smoothing understanding implementation</a></li>
<li><a href="https://stats.stackexchange.com/questions/60257">Markov chain getting stuck due to insufficient data samples</a></li>
<li><a href="https://stats.stackexchange.com/questions/28665">What&#39;s a good approach to estimate the probability of word frequencies?</a></li>
<li><a href="https://stats.stackexchange.com/questions/108618">How to handle unseen features in a Naive Bayes classifier?</a></li>
<li><a href="https://stats.stackexchange.com/questions/108797">In Naive Bayes, why bother with Laplacian smoothing when we have unknown words in the test set?</a></li>
</ol>

<p>(Unsurprisingly, NLP applications seems to generally concerned with this type of regularisation...)</p>
