There is a feature of showing suggested tags after the body of a question is included. These suggestions are based on the body of the question. More details can be found in these posts:
I will quote part of one of the answers, which gives a reasonable summary.
- It uses similar-to-Bayesian reasoning on the text from the title and body of a post
- It has been trained on older questions
- A minimum of around 20k questions are required for accurate results
- There is no substitute for material to learn from, so it can't be rolled out to all sites
If I understand this correctly, this feature is used on Stack Overflow. (In one of the post you can see also a screenshot.) But it can be added to any site which has sufficiently many old questions for training the algorithm. (Ideally, most of the questions should be correctly tagged.)
Still, it seems that some non-trivial work is involved when such a feature is added to a site.
Question. Do you think feature like would be useful on MathOverflow? Should we request Stack Exchange staff to add the feature also to this site?
I have brought this up because a somewhat similar feature request was posted here recently: Why isn't there an automated supertagging? Since these two features are IMO related, it probably makes sense to discuss them at the same time. The difference is basically that in the other feature request the added tags are chosen manually - here by an algorithm; the other feature request suggests to add tags - this one only makes suggestions, the poster might choose some of the suggested tags by clicking on them.