title: How to assign or add a new problem 'label' to an ever-increasing collection of reviews?
body: <p>So basically I have a dataframe which looks like:</p>
  <pre><code>user_id, comment
  0, 'Functional but Horrible UI'
  1, 'Great everything works well'
  2, 'I struggled finding plus button because of theme colors in dark mode'
  3, 'Keeps stopping on Android 10'
  4, 'I like the functionaity but color theme could be better'
  5, 'Consistently crashing. Uninstalled'
  6, 'Good overall'
  7, 'sfdfsdlfksd'
  8, 'I lost in complex settings'
  9, 'Configuring app is really a headache'
  10, 'aaaaaaaaaaaaa'
  </code></pre>
  <p>And I want to figure out some data science approach to pluck out information about what users are struggling with and which issues appeared how much and stuff like this. Even some simple output would be good for me so that we know which parts of app to focus on more. Like for sample above I am aiming for an output as simple as:</p>
  <pre><code>problems = {
  'color_theme': 3,
  'app_settings': 2,
  'crashing' : 2}
  </code></pre>
  <p>So I kinda wants labeling and how much time a label is occured based on to which label a review belongs. For which I have been using manual going throw reviews and understanding whats its about add a count to the relevant bug or if it does not exist, file it which is not getting any easier with ever-increasing number of app reviews. Also the problem is I cannot train a model with predefined labels because:</p>
  <ol>
  <li><p>I do not have labels for reviews. If we have to go through each review to know what problem is it talking about (i.e. to label it), we would just have filed it as well and would know what we have to work on.</p>
  </li>
  <li><p>I do not know in advance what problems are gonna come in future so even if we somehow label all at some point in time, it wouldn't be enough as some unseen problem may come and we have to do again.</p>
  </li>
  <li><p>Even if we have a system of labeling somehow, how would we update model, like do we define a new model with a different architecture for ever changing labels?</p>
  </li>
  </ol>
  <p>So under these circumstances, I was trying to figure out an AI approach to ease in my situation. I am pretty good at python and do have working knowledge of keras/tensorflow and other libraries but none of them seem to have such flexible model approach. I was going through Google Cloud Platform's AI platform as well but it could do sentiment analysis to an extent but not understand in an app context that e.g. button is a part of UI and color as well. So how could I approach this problem in a more elegant way?</p>
  <p>P.S.  Its not really just sentiment analysis as I am getting this response a lot when I discuss this problem. I really only care about negative ratings so for filtering maybe but the actual target is to gather info about how much each problem bothers users and how many users are affected by it so it is not exactly like that. So back to the question:</p>
  <p><strong>How to assign or add a new problem/bug label to an ever-increasing collection of reviews to do analyses with?</strong></p>