Suggested Topics 'limit suggested to category' apparently not working

Hello dears,

In my forum, i have not checked ‘limit suggested to category’

So, I expect, by default, the suggested topics will be the most relevant.


For example, when i wrote an article, i saw some “Your topic is similar to…”

That would be perfect if the suggested topics were that (similar topics).

But instead, it seems to be limited by category:

Is there anything I am missing here?

What is RF Drive Test (Testing)? - Training - telecomHall Forum

Thanks in advance,

If you notice the activity, all those suggested posts were updated recently. Your front page shows you updated a lot of training posts in the last day, so that activity may be contributing a lot to what is shown. Over time I’d expect it to follow the activity. :slight_smile:


I think there is a misunderstanding on how suggested topics work.

We have no algorithm for “similar” suggested topics based on content of a topic. Our algorithm is:

  • Pick unread for user

  • Then pick new for user

  • Then try top pick a bunch of random topics from the category

  • Then if we are still stuck and have room:

    • If limit suggested to category is ticked, bail out

    • If it is not ticked, just pick random topics across categories

No weight is placed on content, tags or participants in the topic. There is no option to say “Hey, just do random across the entire site, if I have no new/unread”

We can not pull in “related topics” cause we would need to redo the whole algorithm to be both more efficient and predictable so it added value.

I guess a question to @codinghorror is if we want a toggle for “Hey, I want super random, don’t try to keep suggested within the category.”

Longer term I can see us exploring machine learning and other models for relevancy but that is not even on our roadmap at the moment.


Don’t you basically already have this though? When you start writing a new topic and put in a title, the preview box will display similar-sounding topics. Couldn’t you reuse that algorithm to fill in the remaining suggested topic slots?

Sort of…

We use trigram similarity and tokenized search to look for stuff while you are typing. Results are uneven.

This kind of works if your topic is very short and you only typed in 200 chars, it falls apart once there is lots of data. Even when it works is uneven.

People do not type 200 words into google when looking for things.

The challenge of getting truly relevant topics based on content a topic has is far more extreme, it would probably involve vectorizing content with word2vec, reducing dimensions and then looking at vector distance. There is much in the AI field written about this problem. It is not trivial at all.

We can not just shove in search + trigrams to look for similarity at a topic level, it will not work even if we cache it. Also there are lots of non content dimensions like number of views and likes that also have some effect on ranking.


I Agree with @seanblue.

You already have the preview box displaing similar-sounding topics.

In my case, it makes total sense.

I think it should at least be an option. User could have the option to decide that the “suggested topics” be the topics shown in preview box whe they start writing a topic.

The suggested topics of my website are often not related to the subject. :frowning:

Ok, i can live with that - but is certainly an improvement that a lot of users would like to see.

Update: as @maiki said, it really got better with time. But, the suggested topics are not the best. In my website, and maybe in someone eleses, it doesn’t matter only the activity. I would like to have the option to show show the suggested topics as they are in preview box.

But it is ok. I would just like to leave my experience and suggestion here. :wink: