<p>Reinforcement learning (RL) is <em>currently</em> on-topic here. However, Stats SE, as we all know, is more statistics-oriented, so there are users here that have no interest in RL, which is a framework for <strong>intelligence</strong> (based on how animals learn): that's why I (and <a href="https://ai.meta.stackexchange.com/a/1450/2444">others that have been answering RL questions both on Stats SE and AI SE</a>) have suggested that Artificial Intelligence SE is the best place to ask theoretical questions related to RL.</p>
<p>In fact, AI SE has the highest number of questions tagged with RL among <a href="https://ai.stackexchange.com/questions/tagged/reinforcement-learning">AI SE</a> (currently, we have 1,548 questions out of 8,057 tagged with RL, so this means that more than 1/8 <span class="math-container">$\approx$</span> 0.19 of the questions are about RL), <a href="https://stats.stackexchange.com/questions/tagged/reinforcement-learning">Stats SE</a> (currently, 908 questions are tagged with RL out of 172,687 questions, so the ratio is about 0.005, which is a lot lower than 0.19), and <a href="https://datascience.stackexchange.com/questions/tagged/reinforcement-learning">Data Science SE</a> (currently, they have 480 questions tagged with RL, out of 26611, for a ratio of 0.01), and almost more than Stack Overflow (which has 1777 questions tagged with RL, with ratio 0.00008). Of course, these ratios are not completely informative of the interests of the community, but they are at least suggestive. In fact, I've personally noticed that many people interested in RL end up on AI SE and they regularly visit the site, and this includes people that answer RL questions even on Stats SE and Data Science SE, as you can see <a href="https://ai.stackexchange.com/tags/reinforcement-learning/topusers">here</a>, <a href="https://stats.stackexchange.com/tags/reinforcement-learning/topusers">here</a> and <a href="https://datascience.stackexchange.com/tags/reinforcement-learning/topusers">here</a>.</p>
<p>If you also look at the most popular tags on these three sites, RL is the 3rd most popular tag (just behind neural networks and machine learning) on AI SE, while, as it should be clear now, it isn't as popular on the other sites.</p>
<p>Although it's true that both AI SE, Stats SE, and Data Science SE are &quot;competing&quot; for users, wouldn't the 3 (overlapping) communities benefit from having a more solid collaboration? I think so.</p>
<p>So, I would suggest that all theoretical RL questions are asked on AI SE. Why? Because of the reasons I just mentioned above (i.e. AI is about intelligence and intelligent agents, and RL is one, if not the main, approach to achieve that), while it's not strictly related to statistics or data science. In this way, all users interested in RL would know that that is THE site where to ask the question and we can decrease the number of questions that went unanswered because the right user that knew about the topic was in another community. <a href="https://stats.meta.stackexchange.com/q/2346/82135">I know that this may not be beneficial for Stats and DS in terms of activity (and some of you will downvote this post because of that)</a>, but, in any case, the amount of activity related to RL in these sites is relatively small (compared to all other topics). As we are all part of SE, we should try to collaborate more so that SE is a place where users can come and get good answers and questions.</p>
<p>So, what do you think about this? Should users on Stats SE and Data Science SE encourage askers to post their RL questions on AI SE? Note that this does not mean that RL questions will be <em>necessarily</em> off-topic on Stats SE or Data Science SE. It only means that we will build more cohesive communities, both in terms of questions and users (with common interests).</p>
